2024 |
Fakriadis, Ioannis; Meiri-Ashkenazi, Iris; Bracha, Chen; Rosenfeld, Hanna; Corriero, Aldo; Zupa, Rosa; Pousis, Chrysovalentinos; Papadaki, Maria; Mylonas, Constantinos C Gonadotropin expression, pituitary and plasma levels in the reproductive cycle of wild and captive-reared greater amberjack (Seriola dumerili) Journal Article General and Comparative Endocrinology, 350 , pp. 114465, 2024, ISSN: 00166480. @article{fakriadis_gonadotropin_2024, title = {Gonadotropin expression, pituitary and plasma levels in the reproductive cycle of wild and captive-reared greater amberjack (Seriola dumerili)}, author = {Ioannis Fakriadis and Iris Meiri-Ashkenazi and Chen Bracha and Hanna Rosenfeld and Aldo Corriero and Rosa Zupa and Chrysovalentinos Pousis and Maria Papadaki and Constantinos C Mylonas}, url = {https://imbbc.hcmr.gr/wp-content/uploads/2024/03/2024-Fakriadis-GCE-12.pdf https://linkinghub.elsevier.com/retrieve/pii/S001664802400025X}, doi = {10.1016/j.ygcen.2024.114465}, issn = {00166480}, year = {2024}, date = {2024-03-05}, urldate = {2024-03-05}, journal = {General and Comparative Endocrinology}, volume = {350}, pages = {114465}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Ventriglia, G; Fakriadis, I; Papadaki, M; Zupa, R; Pousis, C; Mandalakis, M; Corriero, A; Mylonas, C C Effects of different hormonal treatments on spermatogenesis advancement in hatchery-produced greater amberjack Seriola dumerili (Risso 1810) Journal Article 348 , pp. 114447, 2024, ISSN: 00166480. @article{ventriglia_effects_2024, title = {Effects of different hormonal treatments on spermatogenesis advancement in hatchery-produced greater amberjack Seriola dumerili (Risso 1810)}, author = {G Ventriglia and I Fakriadis and M Papadaki and R Zupa and C Pousis and M Mandalakis and A Corriero and C C Mylonas}, url = {https://imbbc.hcmr.gr/wp-content/uploads/2024/02/2024-Ventriglia-GCE-7.pdf https://linkinghub.elsevier.com/retrieve/pii/S0016648024000078}, doi = {10.1016/j.ygcen.2024.114447}, issn = {00166480}, year = {2024}, date = {2024-02-05}, urldate = {2024-02-09}, volume = {348}, pages = {114447}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Lancerotto, Stefano; Fakriadis, Ioannis; Papadaki, Maria; Mandalakis, Manolis; Sigelaki, Irini; Mylonas, Constantinos C Timing of puberty in F1-generation hatchery-produced greater amberjack (Seriola dumerili) Journal Article General and Comparative Endocrinology, 347 , pp. 114414, 2024, ISSN: 00166480. @article{lancerotto_timing_2024, title = {Timing of puberty in F1-generation hatchery-produced greater amberjack (Seriola dumerili)}, author = {Stefano Lancerotto and Ioannis Fakriadis and Maria Papadaki and Manolis Mandalakis and Irini Sigelaki and Constantinos C Mylonas}, url = {https://imbbc.hcmr.gr/wp-content/uploads/2024/01/2024-Lancerotto-GCE-SI-12ISRPF-1.pdf https://linkinghub.elsevier.com/retrieve/pii/S0016648023002198}, doi = {10.1016/j.ygcen.2023.114414}, issn = {00166480}, year = {2024}, date = {2024-01-01}, urldate = {2024-01-10}, journal = {General and Comparative Endocrinology}, volume = {347}, pages = {114414}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
2022 |
Skouradakis, Grigorios; Dounas, Costas; Androulakis, Dimitrios N; Papadaki, Maria; Koulouri, Panayota; Pavlidis, Michail A Study of Arca noae (Linnaeus, 1758) in Elounda Bay, Crete, Eastern Mediterranean Journal Article Journal of Marine Science and Engineering, 10 (5), pp. 673, 2022, ISSN: 2077-1312. @article{skouradakis_study_2022, title = {A Study of Arca noae (Linnaeus, 1758) in Elounda Bay, Crete, Eastern Mediterranean}, author = {Grigorios Skouradakis and Costas Dounas and Dimitrios N Androulakis and Maria Papadaki and Panayota Koulouri and Michail Pavlidis}, url = {https://imbbc.hcmr.gr/wp-content/uploads/2022/07/2022-Skouradakis-jmse-38.pdf https://www.mdpi.com/2077-1312/10/5/673}, doi = {10.3390/jmse10050673}, issn = {2077-1312}, year = {2022}, date = {2022-05-01}, urldate = {2022-07-29}, journal = {Journal of Marine Science and Engineering}, volume = {10}, number = {5}, pages = {673}, abstract = {There is growing interest about marine bivalve aquaculture globally, not only for the market value of the goods produced, but also for the socio-economic and environmental services that this activity can provide. Arca noae is an endemic Mediterranean bivalve of commercial value, whose previously undescribed population in Elounda Bay we studied in terms of its structure and reproduction, while constructing a timeseries of the basic environmental parameters of the bay, thus, gaining fundamental knowledge for the potential future exploitation of the species in the area. We found a variable spatial distribution of arks in the study area, with local high peaks in the population density, consisting of smaller size individuals, in comparison to other areas. Because of protandry of the species, human pressure on this population could have a strong negative effect, by targeting the limited numbers of large females in the study area. The reproduction pattern was similar to the reports from other Mediterranean locations. The abiotic conditions in Elounda Bay differed from those in the adjacent coastal zone, confirming that the Bay is a unique semi-enclosed marine area in the island of Crete.}, keywords = {}, pubstate = {published}, tppubtype = {article} } There is growing interest about marine bivalve aquaculture globally, not only for the market value of the goods produced, but also for the socio-economic and environmental services that this activity can provide. Arca noae is an endemic Mediterranean bivalve of commercial value, whose previously undescribed population in Elounda Bay we studied in terms of its structure and reproduction, while constructing a timeseries of the basic environmental parameters of the bay, thus, gaining fundamental knowledge for the potential future exploitation of the species in the area. We found a variable spatial distribution of arks in the study area, with local high peaks in the population density, consisting of smaller size individuals, in comparison to other areas. Because of protandry of the species, human pressure on this population could have a strong negative effect, by targeting the limited numbers of large females in the study area. The reproduction pattern was similar to the reports from other Mediterranean locations. The abiotic conditions in Elounda Bay differed from those in the adjacent coastal zone, confirming that the Bay is a unique semi-enclosed marine area in the island of Crete. |
Papadaki, Maria; Kaitetzidou, Elisavet; Papadakis, Ioannis E; Sfakianakis, Dimitris G; Papandroulakis, Nikos; Mylonas, Constantinos C; Sarropoulou, Elena Temperature-Biased miRNA Expression Patterns during European Sea Bass (Dicentrarchus labrax) Development Journal Article International Journal of Molecular Sciences, 23 (19), pp. 11164, 2022, ISSN: 1422-0067. @article{papadaki_temperature-biased_2022, title = {Temperature-Biased miRNA Expression Patterns during European Sea Bass (Dicentrarchus labrax) Development}, author = {Maria Papadaki and Elisavet Kaitetzidou and Ioannis E Papadakis and Dimitris G Sfakianakis and Nikos Papandroulakis and Constantinos C Mylonas and Elena Sarropoulou}, url = {https://imbbc.hcmr.gr/wp-content/uploads/2022/09/2022-Papadaki-IJMS-65.pdf https://www.mdpi.com/1422-0067/23/19/11164}, doi = {10.3390/ijms231911164}, issn = {1422-0067}, year = {2022}, date = {2022-01-01}, urldate = {2022-09-27}, journal = {International Journal of Molecular Sciences}, volume = {23}, number = {19}, pages = {11164}, abstract = {Environmental effects and, particularly, temperature changes have been demonstrated to influence the activity, function, and well-being of teleosts. Temperature may change seasonally in the wild, and in captivity under aquaculture operations. Moreover, climate change is expected to shift temperature profiles worldwide. MicroRNAs (miRNA) are important temperature-sensitive gene-expression regulators acting at the post-transcriptional level. They are known to be key regulators in development, reproduction, and immune responses. Therefore, early larval development of the European sea bass (Dicentrarchus labrax), one of the most extensively cultured species in Mediterranean aquaculture, was investigated at early rearing temperatures, i.e., 15, 17.5, and 20 °C, in regard to the impact of temperatures on miRNAs through sncRNA high-throughput sequencing but also at the phenotypic level in terms of growth, sex, vision, and skeletal deformities. Expression profiling revealed stage- and temperature-specific miRNA expression targeting genes with roles in reproduction and immune response mainly at the flexion and all-fins stages. Similar stage- and temperature-specific results were also observed concerning the number of rod cells and lower jaw elongation. The present work presents for the first time highly promising results on the influence of early rearing temperature at the post-transcriptional level during European sea bass development, with a putative impact on reproduction and immune response, as well as regarding teleost vision and larval development.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Environmental effects and, particularly, temperature changes have been demonstrated to influence the activity, function, and well-being of teleosts. Temperature may change seasonally in the wild, and in captivity under aquaculture operations. Moreover, climate change is expected to shift temperature profiles worldwide. MicroRNAs (miRNA) are important temperature-sensitive gene-expression regulators acting at the post-transcriptional level. They are known to be key regulators in development, reproduction, and immune responses. Therefore, early larval development of the European sea bass (Dicentrarchus labrax), one of the most extensively cultured species in Mediterranean aquaculture, was investigated at early rearing temperatures, i.e., 15, 17.5, and 20 °C, in regard to the impact of temperatures on miRNAs through sncRNA high-throughput sequencing but also at the phenotypic level in terms of growth, sex, vision, and skeletal deformities. Expression profiling revealed stage- and temperature-specific miRNA expression targeting genes with roles in reproduction and immune response mainly at the flexion and all-fins stages. Similar stage- and temperature-specific results were also observed concerning the number of rod cells and lower jaw elongation. The present work presents for the first time highly promising results on the influence of early rearing temperature at the post-transcriptional level during European sea bass development, with a putative impact on reproduction and immune response, as well as regarding teleost vision and larval development. |
2021 |
Papadaki, Maria; Mandalakis, Manolis; Anastasiou, Thekla I; Pouli, Marina; Asderis, Michalis; Katharios, Pantelis; Papandroulakis, Nikos; Mylonas, Constantinos C Fish Physiology and Biochemistry, 47 (6), pp. 1777–1792, 2021, ISSN: 1573-5168. @article{papadaki_histological_2021b, title = {Histological evaluation of sex differentiation and early sex identification in hatchery-produced greater amberjack (Seriola dumerili) reared in sea cages}, author = {Maria Papadaki and Manolis Mandalakis and Thekla I Anastasiou and Marina Pouli and Michalis Asderis and Pantelis Katharios and Nikos Papandroulakis and Constantinos C Mylonas}, url = {https://imbbc.hcmr.gr/wp-content/uploads/2022/01/2021-Papadaki-FFB-82-pre-print.pdf https://doi.org/10.1007/s10695-021-01007-7}, doi = {10.1007/s10695-021-01007-7}, issn = {1573-5168}, year = {2021}, date = {2021-12-01}, urldate = {2021-12-04}, journal = {Fish Physiology and Biochemistry}, volume = {47}, number = {6}, pages = {1777--1792}, abstract = {The histological process of gonadal differentiation, together with the endocrine changes of sex steroid hormones and some of their precursors, was studied in hatchery-produced greater amberjack Seriola dumerili from 101 until 408 days post-hatching (dph), with samplings conducted every 50 days. Histological processing showed that sex differentiation began at 101 dph with the formation of the ovarian cavity in females, while the presumptive males did not yet contain any germ cells in their gonad. At 150 dph, we observed the first germ cells in the developing testes. Sex differentiation in almost all sampled individuals was complete at 408 dph. No size dimorphism was observed between the sexes, and the sex ratio was 1:1, suggesting that there was no influence of early rearing in captivity on sex differentiation. Plasma concentrations of adrenosterone (Ad), androstenedione (Δ4), 11-ketotestosterone (11ΚΤ), testosterone (Τ), estradiol (Ε2), progesterone (P4) and 17,20β-dihydroxy-4-pregnen-3-one (17,20βP) were measured in males and females with the use of liquid chromatography tandem mass spectrometry (LC–MS/MS) to examine their role in the sex differentiation process. From the seven hormones, the only one that exhibited differences between the sexes was 11-KT and the plasma 11-KT concentration was found to be a useful indication of greater amberjack sex. Variations were observed in the mean values of Ad, Δ4, 11-KT, T, P4 and 17,20βP over time in one or both sexes, indicating their involvement in the sex differentiation process.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The histological process of gonadal differentiation, together with the endocrine changes of sex steroid hormones and some of their precursors, was studied in hatchery-produced greater amberjack Seriola dumerili from 101 until 408 days post-hatching (dph), with samplings conducted every 50 days. Histological processing showed that sex differentiation began at 101 dph with the formation of the ovarian cavity in females, while the presumptive males did not yet contain any germ cells in their gonad. At 150 dph, we observed the first germ cells in the developing testes. Sex differentiation in almost all sampled individuals was complete at 408 dph. No size dimorphism was observed between the sexes, and the sex ratio was 1:1, suggesting that there was no influence of early rearing in captivity on sex differentiation. Plasma concentrations of adrenosterone (Ad), androstenedione (Δ4), 11-ketotestosterone (11ΚΤ), testosterone (Τ), estradiol (Ε2), progesterone (P4) and 17,20β-dihydroxy-4-pregnen-3-one (17,20βP) were measured in males and females with the use of liquid chromatography tandem mass spectrometry (LC–MS/MS) to examine their role in the sex differentiation process. From the seven hormones, the only one that exhibited differences between the sexes was 11-KT and the plasma 11-KT concentration was found to be a useful indication of greater amberjack sex. Variations were observed in the mean values of Ad, Δ4, 11-KT, T, P4 and 17,20βP over time in one or both sexes, indicating their involvement in the sex differentiation process. |
Mello, Paulo De H; Lancerotto, Stefano; Fakriadis, Ioannis; Tsoukali, Panagiota; Papadaki, Maria; Mylonas, Constantinos Chrysanthos Mediterranean Marine Science, 22 (2), pp. 218–231, 2021, ISSN: 1791-6763. @article{mello_importance_2021, title = {The importance of thermoperiod for proper gametogenesis and successful egg and sperm production in meagre (Argyrosomus regius) breeders in aquaculture}, author = {Paulo De H Mello and Stefano Lancerotto and Ioannis Fakriadis and Panagiota Tsoukali and Maria Papadaki and Constantinos Chrysanthos Mylonas}, url = {https://ejournals.epublishing.ekt.gr/index.php/hcmr-med-mar-sc/article/view/25806 https://imbbc.hcmr.gr/wp-content/uploads/2021/05/2021-De-Mello-MMS-27-2.pdf}, doi = {10.12681/mms.25806}, issn = {1791-6763}, year = {2021}, date = {2021-01-01}, urldate = {2021-04-27}, journal = {Mediterranean Marine Science}, volume = {22}, number = {2}, pages = {218--231}, abstract = {We examined the effect of constant water temperature throughout the year on gametogenesis, spawning success and egg/sperm/embryo quality in meagre (Argyrosomus regius). Two broodstocks were exposed to simulated natural photoperiod, andeither attenuated seasonal water temperature (SeasT, 16.4 to 19.6ºC) or relatively constant water temperature (CoT, 19.4 ± 0.6ºC).In the spawning period (May), 4 couples per group were induced to spawn with gonadotropin releasing hormone agonist (GnRHa). Gonadal stage of development, sperm quality parameters and plasma levels of sex steroids were evaluated prior to the GnRHa treatment. Spawning success and egg/sperm quality were examined over the following 4 weeks. Constant temperature did not prevent gametogenesis, but exposure to attenuated seasonal water temperature with the inclusion of winter low temperature was beneficial to both sexes. The mean (±SD) diameter of the largest vitellogenic oocytes prior to GnRHa administration was significantly higher in the SeasT compared to the CoT group (598 ± 27 vs 520 ± 17 μm). Testosterone plasma levels in the females were significantly higher in the SeasT group, but all other hormones were similar in both sexes. SeasT females spawned more consistently with higher relative fecundity, and 24-h embryo survival of the produced eggs. A more pronounced negative effect of constant water temperature was observed in males, since CoT males exhibited a spermiation index of 0 prior to GnRHa treatment, the latter clearly having a beneficial effect over the following 4 weeks. The study demonstrated that meagre do undergo gametogenesis to a significant extent even under constant water temperatures during the year. However, a seasonal thermal regime -even an attenuated one- was necessary for the proper development of the gametes, allowing for the successful spawning induction using the established GnRHa induction protocol.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We examined the effect of constant water temperature throughout the year on gametogenesis, spawning success and egg/sperm/embryo quality in meagre (Argyrosomus regius). Two broodstocks were exposed to simulated natural photoperiod, andeither attenuated seasonal water temperature (SeasT, 16.4 to 19.6ºC) or relatively constant water temperature (CoT, 19.4 ± 0.6ºC).In the spawning period (May), 4 couples per group were induced to spawn with gonadotropin releasing hormone agonist (GnRHa). Gonadal stage of development, sperm quality parameters and plasma levels of sex steroids were evaluated prior to the GnRHa treatment. Spawning success and egg/sperm quality were examined over the following 4 weeks. Constant temperature did not prevent gametogenesis, but exposure to attenuated seasonal water temperature with the inclusion of winter low temperature was beneficial to both sexes. The mean (±SD) diameter of the largest vitellogenic oocytes prior to GnRHa administration was significantly higher in the SeasT compared to the CoT group (598 ± 27 vs 520 ± 17 μm). Testosterone plasma levels in the females were significantly higher in the SeasT group, but all other hormones were similar in both sexes. SeasT females spawned more consistently with higher relative fecundity, and 24-h embryo survival of the produced eggs. A more pronounced negative effect of constant water temperature was observed in males, since CoT males exhibited a spermiation index of 0 prior to GnRHa treatment, the latter clearly having a beneficial effect over the following 4 weeks. The study demonstrated that meagre do undergo gametogenesis to a significant extent even under constant water temperatures during the year. However, a seasonal thermal regime -even an attenuated one- was necessary for the proper development of the gametes, allowing for the successful spawning induction using the established GnRHa induction protocol. |
Dzyuba, Viktoriya; Cosson, Jacky; Papadaki, Maria; Mylonas, Constantinos C; Steinbach, Christoph; Rodina, Marek; Tučkova, Vladimira; Linhart, Otomar; Shelton, William L; Gela, David; Boryshpolets, Sergii; Dzyuba, Borys Animals, 11 (5), pp. 1417, 2021, ISSN: 2076-2615. @article{dzyuba_influence_2021, title = {Influence of Environmental Temperature and Hormonal Stimulation on the In Vitro Sperm Maturation in Sterlet Acipenser ruthenus in Advance of the Spawning Season}, author = {Viktoriya Dzyuba and Jacky Cosson and Maria Papadaki and Constantinos C Mylonas and Christoph Steinbach and Marek Rodina and Vladimira Tučkova and Otomar Linhart and William L Shelton and David Gela and Sergii Boryshpolets and Borys Dzyuba}, url = {https://imbbc.hcmr.gr/wp-content/uploads/2021/06/2021-Dzyuba-Animals-45.pdf https://www.mdpi.com/2076-2615/11/5/1417}, doi = {10.3390/ani11051417}, issn = {2076-2615}, year = {2021}, date = {2021-01-01}, urldate = {2021-06-24}, journal = {Animals}, volume = {11}, number = {5}, pages = {1417}, abstract = {Sturgeon sperm maturation occurs outside the testes during the transit of testicular spermatozoa (TS) through the kidneys and the Wolffian ducts. A method of in vitro TS maturation in sterlet Acipenser ruthenus was used to investigate the effects of temperature and hormonal stimulation of spermiation on the ability of TS to complete this process. Spermatozoa motility parameters after in vitro maturation of testicular sperm, concentrations of sex steroid hormones and testis morphology were studied in three groups of sterlet: (1) after overwintering in ponds (OW), (2) adapted to spawning temperature (ST), and (3) adapted to spawning temperature with hormonal induction of spermiation (ST-HI). Blood plasma concentrations of testosterone, 11-ketotestosterone and 17,20β-dihydroxy-pregnenolone increased significantly after hormonal induction of spermiation (group ST-HI). In all groups, TS were not motile. After in vitro sperm maturation, motility was up to 60% only in group ST-HI. The data suggest that the ability of TS to be matured in vitro was not related to the environmental temperature, while hormonal stimulation of spermiation during the spawning season was an absolute requirement for optimal in vitro maturation.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Sturgeon sperm maturation occurs outside the testes during the transit of testicular spermatozoa (TS) through the kidneys and the Wolffian ducts. A method of in vitro TS maturation in sterlet Acipenser ruthenus was used to investigate the effects of temperature and hormonal stimulation of spermiation on the ability of TS to complete this process. Spermatozoa motility parameters after in vitro maturation of testicular sperm, concentrations of sex steroid hormones and testis morphology were studied in three groups of sterlet: (1) after overwintering in ponds (OW), (2) adapted to spawning temperature (ST), and (3) adapted to spawning temperature with hormonal induction of spermiation (ST-HI). Blood plasma concentrations of testosterone, 11-ketotestosterone and 17,20β-dihydroxy-pregnenolone increased significantly after hormonal induction of spermiation (group ST-HI). In all groups, TS were not motile. After in vitro sperm maturation, motility was up to 60% only in group ST-HI. The data suggest that the ability of TS to be matured in vitro was not related to the environmental temperature, while hormonal stimulation of spermiation during the spawning season was an absolute requirement for optimal in vitro maturation. |
Chatzifotis, Stavros; Gutiérrez, Abraham Gómez; Papadaki, Maria; Caruso, Fabrizio; Sigelaki, Irini; Mylonas, Constantinos C Fish Physiology and Biochemistry, 47 (4), pp. 1257–1270, 2021, ISSN: 0920-1742, 1573-5168. @article{chatzifotis_lack_2021, title = {Lack of negative effects of fasting of gilthead seabream (Sparus aurata) breeders during the spawning period on maternal and egg nutrient composition, fertilization success, and early embryo/larval development}, author = {Stavros Chatzifotis and Abraham Gómez Gutiérrez and Maria Papadaki and Fabrizio Caruso and Irini Sigelaki and Constantinos C Mylonas}, url = {https://imbbc.hcmr.gr/wp-content/uploads/2021/07/2021-Chatzifotis2021_Article_LackOfNegativeEffectsOfFasting-pre-print-57.pdf https://link.springer.com/10.1007/s10695-021-00979-w}, doi = {10.1007/s10695-021-00979-w}, issn = {0920-1742, 1573-5168}, year = {2021}, date = {2021-01-01}, urldate = {2021-07-26}, journal = {Fish Physiology and Biochemistry}, volume = {47}, number = {4}, pages = {1257--1270}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Papadaki, Maria; Mandalakis, Manolis; Anastasiou, Thekla I; Pouli, Marina; Asderis, Michalis; Katharios, Pantelis; Papandroulakis, Nikos; Mylonas, Constantinos C Fish Physiology and Biochemistry, 47 (6), pp. 1777–1792, 2021, ISSN: 1573-5168. @article{papadaki_histological_2021, title = {Histological evaluation of sex differentiation and early sex identification in hatchery-produced greater amberjack (Seriola dumerili) reared in sea cages}, author = {Maria Papadaki and Manolis Mandalakis and Thekla I Anastasiou and Marina Pouli and Michalis Asderis and Pantelis Katharios and Nikos Papandroulakis and Constantinos C Mylonas}, url = {https://imbbc.hcmr.gr/wp-content/uploads/2021/12/2021-Papadaki-FFB-69-pre-print-1.pdf https://doi.org/10.1007/s10695-021-01007-7}, doi = {10.1007/s10695-021-01007-7}, issn = {1573-5168}, year = {2021}, date = {2021-01-01}, urldate = {2021-12-04}, journal = {Fish Physiology and Biochemistry}, volume = {47}, number = {6}, pages = {1777--1792}, abstract = {The histological process of gonadal differentiation, together with the endocrine changes of sex steroid hormones and some of their precursors, was studied in hatchery-produced greater amberjack Seriola dumerili from 101 until 408 days post-hatching (dph), with samplings conducted every 50 days. Histological processing showed that sex differentiation began at 101 dph with the formation of the ovarian cavity in females, while the presumptive males did not yet contain any germ cells in their gonad. At 150 dph, we observed the first germ cells in the developing testes. Sex differentiation in almost all sampled individuals was complete at 408 dph. No size dimorphism was observed between the sexes, and the sex ratio was 1:1, suggesting that there was no influence of early rearing in captivity on sex differentiation. Plasma concentrations of adrenosterone (Ad), androstenedione (Δ4), 11-ketotestosterone (11ΚΤ), testosterone (Τ), estradiol (Ε2), progesterone (P4) and 17,20β-dihydroxy-4-pregnen-3-one (17,20βP) were measured in males and females with the use of liquid chromatography tandem mass spectrometry (LC–MS/MS) to examine their role in the sex differentiation process. From the seven hormones, the only one that exhibited differences between the sexes was 11-KT and the plasma 11-KT concentration was found to be a useful indication of greater amberjack sex. Variations were observed in the mean values of Ad, Δ4, 11-KT, T, P4 and 17,20βP over time in one or both sexes, indicating their involvement in the sex differentiation process.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The histological process of gonadal differentiation, together with the endocrine changes of sex steroid hormones and some of their precursors, was studied in hatchery-produced greater amberjack Seriola dumerili from 101 until 408 days post-hatching (dph), with samplings conducted every 50 days. Histological processing showed that sex differentiation began at 101 dph with the formation of the ovarian cavity in females, while the presumptive males did not yet contain any germ cells in their gonad. At 150 dph, we observed the first germ cells in the developing testes. Sex differentiation in almost all sampled individuals was complete at 408 dph. No size dimorphism was observed between the sexes, and the sex ratio was 1:1, suggesting that there was no influence of early rearing in captivity on sex differentiation. Plasma concentrations of adrenosterone (Ad), androstenedione (Δ4), 11-ketotestosterone (11ΚΤ), testosterone (Τ), estradiol (Ε2), progesterone (P4) and 17,20β-dihydroxy-4-pregnen-3-one (17,20βP) were measured in males and females with the use of liquid chromatography tandem mass spectrometry (LC–MS/MS) to examine their role in the sex differentiation process. From the seven hormones, the only one that exhibited differences between the sexes was 11-KT and the plasma 11-KT concentration was found to be a useful indication of greater amberjack sex. Variations were observed in the mean values of Ad, Δ4, 11-KT, T, P4 and 17,20βP over time in one or both sexes, indicating their involvement in the sex differentiation process. |
2020 |
Fakriadis, Ioannis; Zanatta, Eugenio Maria; Fleck, Renata Pontes Dos Santos; Mateo, Daybet Lorena Sena; Papadaki, Maria; Mylonas, Constantinos C Endocrine regulation of long-term enhancement of spermiation in meagre (Argyrosomus regius) with GnRHa controlled-delivery systems Journal Article General and Comparative Endocrinology, 297 , pp. 113549, 2020, ISSN: 00166480. @article{fakriadis_endocrine_2020, title = {Endocrine regulation of long-term enhancement of spermiation in meagre (Argyrosomus regius) with GnRHa controlled-delivery systems}, author = {Ioannis Fakriadis and Eugenio Maria Zanatta and Renata Pontes Dos Santos Fleck and Daybet Lorena Sena Mateo and Maria Papadaki and Constantinos C Mylonas}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0016648020303026}, doi = {10.1016/j.ygcen.2020.113549}, issn = {00166480}, year = {2020}, date = {2020-10-01}, urldate = {2020-08-06}, journal = {General and Comparative Endocrinology}, volume = {297}, pages = {113549}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Papadaki, Maria; Kaitetzidou, Elisavet; Mylonas, Constantinos C; Sarropoulou, Elena Non-coding RNA Expression Patterns of Two Different Teleost Gonad Maturation Stages Journal Article Marine Biotechnology, 22 (5), pp. 683–695, 2020, ISSN: 1436-2228, 1436-2236. @article{papadaki_non-coding_2020, title = {Non-coding RNA Expression Patterns of Two Different Teleost Gonad Maturation Stages}, author = {Maria Papadaki and Elisavet Kaitetzidou and Constantinos C Mylonas and Elena Sarropoulou}, url = {http://link.springer.com/10.1007/s10126-020-09991-2 https://imbbc.hcmr.gr/wp-content/uploads/2020/10/Papadaki-2020-MBTE-pre-print.pdf}, doi = {10.1007/s10126-020-09991-2}, issn = {1436-2228, 1436-2236}, year = {2020}, date = {2020-10-01}, urldate = {2020-10-05}, journal = {Marine Biotechnology}, volume = {22}, number = {5}, pages = {683--695}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Fakriadis, Ioannis; Sigelaki, Irini; Papadaki, Maria; Papandroulakis, Nikos; Raftopoulos, Anastasios; Tsakoniti, Kalliopi; Mylonas, Constantinos C Control of reproduction of greater amberjack Seriola dumerili reared in aquaculture facilities Journal Article Aquaculture, 519 , 2020, ISSN: 00448486, (Type: Journal Article). @article{fakriadis_control_2020, title = {Control of reproduction of greater amberjack Seriola dumerili reared in aquaculture facilities}, author = {Ioannis Fakriadis and Irini Sigelaki and Maria Papadaki and Nikos Papandroulakis and Anastasios Raftopoulos and Kalliopi Tsakoniti and Constantinos C Mylonas}, url = {https://pdf.sciencedirectassets.com/271224/1-s2.0-S0044848619X00186/1-s2.0-S0044848619326079/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjEPb%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJGMEQCIEKiYyI3Ycqx63hZp9lWGRWcsYrKIYv1T3L%2FsVCZBXRLAiBT0R83WGN4OE%2BrF0Q2Iy1lEA1RMiC7UHkh9ziKtbtPFyq9Awie%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F8BEAIaDDA1OTAwMzU0Njg2NSIM4gS7FIQr6cp11X0pKpED%2FgoocYExFYA%2FLlo%2FsWYyzGVglS%2F6nkMLmZ%2ByMzYN3rGpSS8JnjWll%2BVBi9%2BQFiROQwjuZa3a%2FSAaLIRpIrqFJha5oaFJ1uYLfF5jH%2F62tRXpLB7sJQIii2PJpKgyFJfvrf62rUnhlVgggKANKBLslRjOQC8OAM6eh7pVSbTEeL5L2u1qmbgrN9sofvTRJjUhHYH6khAKTlWIN9Ms%2Bh%2FOYQd4hTDsXfs%2FCLNjH1yWN8vg5BwKN2LzwxBg4GRzlAPYuHtntee5qvC66DnoixqeUW9OTaf0KEv%2BJzwpT%2BfYdAWgXADTRYyGrESV0DPkx1DtTDORWmCg3rcA%2B2uudNnFW9OTbzBVItC8f9kdRQFCebf%2B8oUZjaQmpd6%2F9JT5xdXN8nmLLSD4B9f7HP4U9JMaLZ2mn8tdIZKFXY4RDIy4GDSatfnMgb2XPIRgWuB2PVcXkSf5FZFJA0%2BJ%2BNmXPCeB%2Brw8JB7L5LUaBqTpvV1HsryDzFT1ldBoXdenkb%2BNqHmCOXfEy1ym7f%2F1nzvO3WzGaPowo8Lu8QU67AFeu9OlXRP%2B4WswxYSqWZm5HLdCiyyyTFj51GbkOMdIlPKhnTIAVKhItiILXu%2BV72DuKLFa6Oi1iniDXP8KMQsuMUWjfimxW%2BdiyAeYmLmZMp09D130PUxEC8%2FPLMEyv0fXQY5U1q%2FlsoZwTHIjrGSmzdX9AV1AlVjKx9p6qyJ4fvBE%2BYBdfStdOdO5NaTrkff5pVoEXP1prc2HPySs%2BQ%2F%2FewSGTNjeUJHZDoVDpd17GFYHLwhoEHbOGt54OFz4kAAaHRh3S60uJxwRA6gSMwO%2But3nF4rDdIJSmL3QNM%2BO%2FY%2FK%2FF1ZYvaprhEPdQ%3D%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20200206T064417Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTYU72A2J4J%2F20200206%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=ea8ff719b68d48407c48376c1561efa9042ae1f7598e65d269d5ba562bbe8262&hash=a4e2bfffdc3a781228d030d4043afc6504ec3ebb0665612a27237bc5a0c78826&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0044848619326079&tid=spdf-0066909c-c2cd-42a5-964f-1088618050da&sid=9f8cc34964ace14eda7b5f0927495aa20829gxrqb&type=client}, doi = {10.1016/j.aquaculture.2019.734880}, issn = {00448486}, year = {2020}, date = {2020-01-01}, journal = {Aquaculture}, volume = {519}, note = {Type: Journal Article}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
2019 |
Pérez, Evaristo; Linares, Fátima; Villanueva, José Luis Rodríguez; Vilar, Antonio; Mylonas, Constantinos C; Fakriadis, Ioannis; Papadaki, Maria; Papandroulakis, Nikos; Papadakis, Ioannis; Robles, Rocío; Fauvel, Christian; Roo, Javier; Peleteiro, José Benito; Lluch, Nuria; Pazos, Gema; Méndez, Belén; Sigelaki, Irini; Gómez, Castora; Pérez, Montse; Álvarez-Blázquez, Blanca Wreckfish (Polyprion americanus). New Knowledge About Reproduction, Larval Husbandry, and Nutrition. Promise as a New Species for Aquaculture Journal Article Fishes, 4 (1), pp. 14, 2019, (Type: Journal Article). @article{perez_wreckfish_2019, title = {Wreckfish (Polyprion americanus). New Knowledge About Reproduction, Larval Husbandry, and Nutrition. Promise as a New Species for Aquaculture}, author = {Evaristo Pérez and Fátima Linares and José Luis Rodríguez Villanueva and Antonio Vilar and Constantinos C Mylonas and Ioannis Fakriadis and Maria Papadaki and Nikos Papandroulakis and Ioannis Papadakis and Rocío Robles and Christian Fauvel and Javier Roo and José Benito Peleteiro and Nuria Lluch and Gema Pazos and Belén Méndez and Irini Sigelaki and Castora Gómez and Montse Pérez and Blanca Álvarez-Blázquez}, year = {2019}, date = {2019-01-01}, journal = {Fishes}, volume = {4}, number = {1}, pages = {14}, note = {Type: Journal Article}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Forner-Piquer, Isabel; Mylonas, Constantinos C; Fakriadis, Ioannis; Papadaki, Maria; Piscitelli, Fabiana; Marzo, Vincenzo Di; Calduch-Giner, Josep; Pérez-Sánchez, Jaume; Carnevali, Oliana Archives of Toxicology, 2019, ISSN: 1432-0738, (Type: Journal Article). @article{forner-piquer_effects_2019-1, title = {Effects of diisononyl phthalate (DiNP) on the endocannabinoid and reproductive systems of male gilthead sea bream (Sparus aurata) during the spawning season}, author = {Isabel Forner-Piquer and Constantinos C Mylonas and Ioannis Fakriadis and Maria Papadaki and Fabiana Piscitelli and Vincenzo Di Marzo and Josep Calduch-Giner and Jaume Pérez-Sánchez and Oliana Carnevali}, url = {https://doi.org/10.1007/s00204-018-2378-6}, doi = {10.1007/s00204-018-2378-6}, issn = {1432-0738}, year = {2019}, date = {2019-01-01}, journal = {Archives of Toxicology}, note = {Type: Journal Article}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Fakriadis, I; Lisi, F; Sigelaki, I; Papadaki, M; Mylonas, C C Spawning kinetics and egg/larval quality of greater amberjack (Seriola dumerili) in response to multiple GnRHa injections or implants Journal Article General and Comparative Endocrinology, 279 , pp. 78–87, 2019, ISSN: 1095-6840 (Electronic) 0016-6480 (Linking), (Type: Journal Article). @article{fakriadis_spawning_2019, title = {Spawning kinetics and egg/larval quality of greater amberjack (Seriola dumerili) in response to multiple GnRHa injections or implants}, author = {I Fakriadis and F Lisi and I Sigelaki and M Papadaki and C C Mylonas}, url = {https://www.ncbi.nlm.nih.gov/pubmed/30571964 https://www.sciencedirect.com/science/article/pii/S0016648018304726?via%3Dihub}, doi = {10.1016/j.ygcen.2018.12.007}, issn = {1095-6840 (Electronic) 0016-6480 (Linking)}, year = {2019}, date = {2019-01-01}, journal = {General and Comparative Endocrinology}, volume = {279}, pages = {78--87}, note = {Type: Journal Article}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
2018 |
Pousis, C; Mylonas, C C; Virgilio, De C; Gadaleta, G; Santamaria, N; Passantino, L; Zupa, R; Papadaki, M; Fakriadis, I; Ferreri, R; Corriero, A Aquaculture Research, 49 (1), pp. 243–252, 2018, ISSN: 1355557X, (Publisher: Blackwell Publishing Ltd). @article{pousis_observed_2018, title = {The observed oogenesis impairment in greater amberjack Seriola dumerili (Risso, 1810) reared in captivity is not related to an insufficient liver transcription or oocyte uptake of vitellogenin}, author = {C Pousis and C C Mylonas and C De Virgilio and G Gadaleta and N Santamaria and L Passantino and R Zupa and M Papadaki and I Fakriadis and R Ferreri and A Corriero}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85026499054&doi=10.1111%2fare.13453&partnerID=40&md5=ecb8f6c6b9bbbf8b803322299447cfd4}, doi = {10.1111/are.13453}, issn = {1355557X}, year = {2018}, date = {2018-01-01}, journal = {Aquaculture Research}, volume = {49}, number = {1}, pages = {243--252}, abstract = {The greater amberjack Seriola dumerili is an excellent candidate for the Mediterranean aquaculture, due to its large body size and high growth rate, as well as its high flesh quality and commercial value worldwide. For its successful incorporation in the aquaculture industry, an in-depth understanding of the reproductive function of the species under rearing conditions is necessary, since completion of oogenesis in captivity is currently a bottleneck for the commercial production of the species. Liver and ovary samples from wild and captive-reared greater amberjack females were collected at three different phases of the reproductive cycle: early gametogenesis (EARLY, late April-early May), advanced gametogenesis (ADVANCED, late May-early June) and spawning (SPAWNING, late June-July). The cDNAs of three vitellogenins (VtgA, VtgB and VtgC) were partially sequenced and a qRT-PCR for their expression was used to compare ovarian maturity stage and liver vitellogenin transcript levels between wild and captive-reared individuals. An extensive atresia of late vitellogenic follicles, which prevented any further oocyte development and spawning was observed in captive-reared individuals during the ADVANCED phase. The expression levels of the three vitellogenins, as well as the amount of yolk globules in vitellogenic oocytes, did not differ significantly between captive-reared and wild females, indicating that the observed oogenesis impairment in greater amberjack reared in captivity was not related to an insufficient liver synthesis or a reduced oocyte uptake of vitellogenin. © 2017 John Wiley & Sons Ltd}, note = {Publisher: Blackwell Publishing Ltd}, keywords = {}, pubstate = {published}, tppubtype = {article} } The greater amberjack Seriola dumerili is an excellent candidate for the Mediterranean aquaculture, due to its large body size and high growth rate, as well as its high flesh quality and commercial value worldwide. For its successful incorporation in the aquaculture industry, an in-depth understanding of the reproductive function of the species under rearing conditions is necessary, since completion of oogenesis in captivity is currently a bottleneck for the commercial production of the species. Liver and ovary samples from wild and captive-reared greater amberjack females were collected at three different phases of the reproductive cycle: early gametogenesis (EARLY, late April-early May), advanced gametogenesis (ADVANCED, late May-early June) and spawning (SPAWNING, late June-July). The cDNAs of three vitellogenins (VtgA, VtgB and VtgC) were partially sequenced and a qRT-PCR for their expression was used to compare ovarian maturity stage and liver vitellogenin transcript levels between wild and captive-reared individuals. An extensive atresia of late vitellogenic follicles, which prevented any further oocyte development and spawning was observed in captive-reared individuals during the ADVANCED phase. The expression levels of the three vitellogenins, as well as the amount of yolk globules in vitellogenic oocytes, did not differ significantly between captive-reared and wild females, indicating that the observed oogenesis impairment in greater amberjack reared in captivity was not related to an insufficient liver synthesis or a reduced oocyte uptake of vitellogenin. © 2017 John Wiley & Sons Ltd |
Papadaki, M; Mazzella, D; Santinelli, V; Fakriadis, I; Sigelaki, I; Mylonas, C C Hermaphroditism and reproductive function of hatchery-produced sharpsnout seabream (Diplodus puntazzo) under attenuated annual thermal cycles Journal Article Aquaculture, 482 , pp. 231–240, 2018, ISSN: 00448486, (Publisher: Elsevier B.V.). @article{papadaki_hermaphroditism_2018, title = {Hermaphroditism and reproductive function of hatchery-produced sharpsnout seabream (Diplodus puntazzo) under attenuated annual thermal cycles}, author = {M Papadaki and D Mazzella and V Santinelli and I Fakriadis and I Sigelaki and C C Mylonas}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85030865182&doi=10.1016%2fj.aquaculture.2017.09.028&partnerID=40&md5=61ad82357d509cb8f19491299ca570e0}, doi = {10.1016/j.aquaculture.2017.09.028}, issn = {00448486}, year = {2018}, date = {2018-01-01}, journal = {Aquaculture}, volume = {482}, pages = {231--240}, abstract = {Acquiring more knowledge on the reproductive biology of the sharpsnout seabream (Diplodus puntazzo) can improve our ability to control its reproduction and enable hatcheries to reconsider this fish as a potential species for the Mediterranean aquaculture production. We investigated hermaphroditism and reproductive function in a hatchery-produced broodstock over a long period of 6 years, which includes sex differentiation, puberty and four consecutive annual reproductive seasons, at relatively constant water temperatures of 18–20 °C, which are typical of borehole seawater supplies used frequently in marine hatcheries for biosecurity reasons. At the end of the first year of life, the gonads were bisexual and were classified into three different categories: mainly testicular tissue with rudimentary ovarian tissue (Mf), substantial amounts of both tissues (MF) and mainly ovarian tissue with rudimentary testicular tissue (mF). Fully female (F) gonads appeared already in 1 + years old fish, whereas fully male (M) gonads appeared for the first time in 2 + years old fish. The sex ratio (F:M) of the studied populations during the first 6 years of life in all age classes was not different from 1:1. Therefore, no annual restructuring of the broodstock is necessary in order to avoid the development of skewed sex ratios, since once functional sex is established it does not seem to change in the following years. Furthermore, the use of attenuated annual thermal cycling regimes did not seem to affect the annual gametogenic cycle and full maturation of this species, though spontaneous spawning was still missing and the fish exhibited the typical problems reported for this species in captivity. © 2017 Elsevier B.V.}, note = {Publisher: Elsevier B.V.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Acquiring more knowledge on the reproductive biology of the sharpsnout seabream (Diplodus puntazzo) can improve our ability to control its reproduction and enable hatcheries to reconsider this fish as a potential species for the Mediterranean aquaculture production. We investigated hermaphroditism and reproductive function in a hatchery-produced broodstock over a long period of 6 years, which includes sex differentiation, puberty and four consecutive annual reproductive seasons, at relatively constant water temperatures of 18–20 °C, which are typical of borehole seawater supplies used frequently in marine hatcheries for biosecurity reasons. At the end of the first year of life, the gonads were bisexual and were classified into three different categories: mainly testicular tissue with rudimentary ovarian tissue (Mf), substantial amounts of both tissues (MF) and mainly ovarian tissue with rudimentary testicular tissue (mF). Fully female (F) gonads appeared already in 1 + years old fish, whereas fully male (M) gonads appeared for the first time in 2 + years old fish. The sex ratio (F:M) of the studied populations during the first 6 years of life in all age classes was not different from 1:1. Therefore, no annual restructuring of the broodstock is necessary in order to avoid the development of skewed sex ratios, since once functional sex is established it does not seem to change in the following years. Furthermore, the use of attenuated annual thermal cycling regimes did not seem to affect the annual gametogenic cycle and full maturation of this species, though spontaneous spawning was still missing and the fish exhibited the typical problems reported for this species in captivity. © 2017 Elsevier B.V. |
Jerez, Salvador; Fakriadis, Ioannis; Papadaki, Maria; Martín, M; Cejas, Juana; Mylonas, Constantinos C Spawning induction of first-generation (F1) greater amberjack Seriola dumerili in the Canary Islands, Spain using GnRHa delivery systems Journal Article Fishes, 3 (3), pp. 1–22, 2018, ISSN: 2410-3888, (Type: Journal Article). @article{jerez_spawning_2018, title = {Spawning induction of first-generation (F1) greater amberjack Seriola dumerili in the Canary Islands, Spain using GnRHa delivery systems}, author = {Salvador Jerez and Ioannis Fakriadis and Maria Papadaki and M Martín and Juana Cejas and Constantinos C Mylonas}, url = {https://res.mdpi.com/fishes/fishes-03-00035/article_deploy/fishes-03-00035.pdf?filename=&attachment=1}, doi = {10.3390/fishes3030035}, issn = {2410-3888}, year = {2018}, date = {2018-01-01}, journal = {Fishes}, volume = {3}, number = {3}, pages = {1--22}, note = {Type: Journal Article}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Papadaki, Maria; Peleteiro, José Benito; Alvarez-Blázquez, Blanca; Villanueva, José Luis Rodríguez; Linares, Fatima; Vilar, Antonio; Rial, Evaristo Pérez; Lluch, Nuria; Fakriadis, Ioannis; Sigelaki, Irini; Mylonas, Constantinos C Description of the Annual Reproductive Cycle of Wreckfish Polyprion americanus in Captivity Journal Article Fishes, 3 (4), pp. 1–20, 2018, ISSN: 2410-3888, (Type: Journal Article). @article{papadaki_description_2018, title = {Description of the Annual Reproductive Cycle of Wreckfish Polyprion americanus in Captivity}, author = {Maria Papadaki and José Benito Peleteiro and Blanca Alvarez-Blázquez and José Luis Rodríguez Villanueva and Fatima Linares and Antonio Vilar and Evaristo Pérez Rial and Nuria Lluch and Ioannis Fakriadis and Irini Sigelaki and Constantinos C Mylonas}, url = {https://res.mdpi.com/fishes/fishes-03-00043/article_deploy/fishes-03-00043.pdf?filename=&attachment=1}, doi = {10.3390/fishes3040043}, issn = {2410-3888}, year = {2018}, date = {2018-01-01}, journal = {Fishes}, volume = {3}, number = {4}, pages = {1--20}, note = {Type: Journal Article}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
2017 |
Zupa, R; Rodrõâguez, C; Mylonas, C C; Rosenfeld, H; Fakriadis, I; Papadaki, M; Peârez, J A; Pousis, C; Basilone, G; Corriero, A Comparative study of reproductive development in wild and captive-reared greater amberjack seriola dumerili (Risso, 1810) Journal Article PLoS ONE, 12 (1), 2017, ISSN: 19326203, (Publisher: Public Library of Science). @article{zupa_comparative_2017, title = {Comparative study of reproductive development in wild and captive-reared greater amberjack seriola dumerili (Risso, 1810)}, author = {R Zupa and C Rodrõâguez and C C Mylonas and H Rosenfeld and I Fakriadis and M Papadaki and J A Peârez and C Pousis and G Basilone and A Corriero}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85008686824&doi=10.1371%2fjournal.pone.0169645&partnerID=40&md5=09301e14b368a835887bf0e7176db149}, doi = {10.1371/journal.pone.0169645}, issn = {19326203}, year = {2017}, date = {2017-01-01}, journal = {PLoS ONE}, volume = {12}, number = {1}, abstract = {The greater amberjack Seriola dumerili is a large teleost fish with rapid growth and excellent flesh quality, whose domestication represents an ambitious challenge for aquaculture. The occurrence of reproductive dysfunctions in greater amberjack reared in captivity was investigated by comparing reproductive development of wild and captive-reared individuals. Wild and captive-reared breeders were sampled in the Mediterranean Sea during three different phases of the reproductive cycle: Early gametogenesis (EARLY, late April-early May), advanced gametogenesis (ADVANCED, late May-early June) and spawning (SPAWNING, late June-July). Fish reproductive state was evaluated using the gonado-somatic index (GSI), histological analysis of the gonads and determination of sex steroid levels in the plasma, and correlated with leptin expression in the liver and gonad biochemical composition. The GSI and sex steroid levels were lower in captive-reared than in wild fish. During the ADVANCED period, when the wild greater amberjack breeders were already in spawning condition, ovaries of captive-reared breeders showed extensive atresia of late vitellogenic oocytes and spermatogenic activity ceased in the testes of half of the examined males. During the SPAWNING period, all captive-reared fish had regressed gonads, while wild breeders still displayed reproductive activity. Liver leptin expression and gonad proximate composition of wild and captive greater amberjack were similar. However, the gonads of captive-reared fish showed different total polar lipid contents, as well as specific lipid classes and fatty acid profiles with respect to wild individuals. This study underlines the need for an improvement in rearing technology for this species, which should include minimum handling during the reproductive season and the formulation of a specific diet to overcome the observed gonadal decrements of phospholipids, DHA (22:6n-3) and ARA (20:4n-6), compared to wild breeders. © 2017 Zupa et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.}, note = {Publisher: Public Library of Science}, keywords = {}, pubstate = {published}, tppubtype = {article} } The greater amberjack Seriola dumerili is a large teleost fish with rapid growth and excellent flesh quality, whose domestication represents an ambitious challenge for aquaculture. The occurrence of reproductive dysfunctions in greater amberjack reared in captivity was investigated by comparing reproductive development of wild and captive-reared individuals. Wild and captive-reared breeders were sampled in the Mediterranean Sea during three different phases of the reproductive cycle: Early gametogenesis (EARLY, late April-early May), advanced gametogenesis (ADVANCED, late May-early June) and spawning (SPAWNING, late June-July). Fish reproductive state was evaluated using the gonado-somatic index (GSI), histological analysis of the gonads and determination of sex steroid levels in the plasma, and correlated with leptin expression in the liver and gonad biochemical composition. The GSI and sex steroid levels were lower in captive-reared than in wild fish. During the ADVANCED period, when the wild greater amberjack breeders were already in spawning condition, ovaries of captive-reared breeders showed extensive atresia of late vitellogenic oocytes and spermatogenic activity ceased in the testes of half of the examined males. During the SPAWNING period, all captive-reared fish had regressed gonads, while wild breeders still displayed reproductive activity. Liver leptin expression and gonad proximate composition of wild and captive greater amberjack were similar. However, the gonads of captive-reared fish showed different total polar lipid contents, as well as specific lipid classes and fatty acid profiles with respect to wild individuals. This study underlines the need for an improvement in rearing technology for this species, which should include minimum handling during the reproductive season and the formulation of a specific diet to overcome the observed gonadal decrements of phospholipids, DHA (22:6n-3) and ARA (20:4n-6), compared to wild breeders. © 2017 Zupa et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. |
2015 |
Mylonas, C C; Fatira, E; Karkut, P; Papadaki, M; Sigelaki, I; Duncan, N J Aquaculture, 448 , pp. 44–53, 2015, ISSN: 00448486, (Publisher: Elsevier). @article{mylonas_reproduction_2015, title = {Reproduction of hatchery-produced meagre Argyrosomus regius in captivity III. Comparison between GnRHa implants and injections on spawning kinetics and egg/larval performance parameters}, author = {C C Mylonas and E Fatira and P Karkut and M Papadaki and I Sigelaki and N J Duncan}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84930649334&doi=10.1016%2fj.aquaculture.2015.05.036&partnerID=40&md5=166818b9c8f787751aa632ac652d6bb1}, doi = {10.1016/j.aquaculture.2015.05.036}, issn = {00448486}, year = {2015}, date = {2015-01-01}, journal = {Aquaculture}, volume = {448}, pages = {44--53}, abstract = {Hatchery-produced meagre (Argyrosomus regius) were induced to spawn using either controlled-release delivery systems (implants) loaded with gonadotropin-releasing hormone agonist (GnRHa) or GnRHa injections. Over two consecutive years, individual females were paired with single males after treatment with a GnRHa implant (40-104μgkg-1) or a GnRHa injection (15-25μgkg-1). Three consecutive GnRHa implants were given every 20-30days, while five (in 2012) or seven (in 2013) consecutive GnRHa injections were given every 10days. Fecundity and fertilization success was evaluated the day of spawning, and embryo/larval development was evaluated using 96-well microtiter plates. The first implantation with GnRHa produced up to 23 almost daily spawns, but most females failed to spawn repeatedly after the second implantation, even though their ovaries contained significant numbers of post-vitellogenic oocytes. Most of the eggs were produced in the first 3-4 spawns after GnRHa implantation, while the remaining batches were of low fecundity, which related directly to low fertilization. On the other hand, GnRHa injections produced consistently two spawns on days 2 and 3 after each treatment. Fecundity also decreased over time in response to the subsequent injections, but the response was more gradual and less dramatic than in GnRHa implanted females. Although both methods produced similar overall results in terms of total fecundity and egg/larval quality, multiple GnRHa injections resulted in more consistent spawning results and better egg production control, and this method may offer significant advantages over the use of controlled-release GnRHa implants. Statement of relevance: We present an efficient spawning induction method for meagre, which is the result of extensive experimentation both in previously published works, as well as in this one. The resulting method is proposed for its effectiveness and efficiency to the aquaculture industry. © 2015 Elsevier B.V..}, note = {Publisher: Elsevier}, keywords = {}, pubstate = {published}, tppubtype = {article} } Hatchery-produced meagre (Argyrosomus regius) were induced to spawn using either controlled-release delivery systems (implants) loaded with gonadotropin-releasing hormone agonist (GnRHa) or GnRHa injections. Over two consecutive years, individual females were paired with single males after treatment with a GnRHa implant (40-104μgkg-1) or a GnRHa injection (15-25μgkg-1). Three consecutive GnRHa implants were given every 20-30days, while five (in 2012) or seven (in 2013) consecutive GnRHa injections were given every 10days. Fecundity and fertilization success was evaluated the day of spawning, and embryo/larval development was evaluated using 96-well microtiter plates. The first implantation with GnRHa produced up to 23 almost daily spawns, but most females failed to spawn repeatedly after the second implantation, even though their ovaries contained significant numbers of post-vitellogenic oocytes. Most of the eggs were produced in the first 3-4 spawns after GnRHa implantation, while the remaining batches were of low fecundity, which related directly to low fertilization. On the other hand, GnRHa injections produced consistently two spawns on days 2 and 3 after each treatment. Fecundity also decreased over time in response to the subsequent injections, but the response was more gradual and less dramatic than in GnRHa implanted females. Although both methods produced similar overall results in terms of total fecundity and egg/larval quality, multiple GnRHa injections resulted in more consistent spawning results and better egg production control, and this method may offer significant advantages over the use of controlled-release GnRHa implants. Statement of relevance: We present an efficient spawning induction method for meagre, which is the result of extensive experimentation both in previously published works, as well as in this one. The resulting method is proposed for its effectiveness and efficiency to the aquaculture industry. © 2015 Elsevier B.V.. |
2013 |
Zupa, R; Fauvel, C; Mylonas, C C; Santamaria, N; Valentini, L; Pousis, C; Papadaki, M; Suquet, M; la Gándara, De F; Bello, G; Metrio, De G; Corriero, A Comparative analysis of male germ cell proliferation and apoptosis in wild and captive Atlantic bluefin tuna (Thunnus thynnus L.) Journal Article Journal of Applied Ichthyology, 29 (1), pp. 71–81, 2013, ISSN: 01758659. @article{zupa_comparative_2013, title = {Comparative analysis of male germ cell proliferation and apoptosis in wild and captive Atlantic bluefin tuna (Thunnus thynnus L.)}, author = {R Zupa and C Fauvel and C C Mylonas and N Santamaria and L Valentini and C Pousis and M Papadaki and M Suquet and F De la Gándara and G Bello and G De Metrio and A Corriero}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84872311647&doi=10.1111%2fj.1439-0426.2012.02045.x&partnerID=40&md5=286c3d6def7c6fa6ee4d801b0c86665c}, doi = {10.1111/j.1439-0426.2012.02045.x}, issn = {01758659}, year = {2013}, date = {2013-01-01}, journal = {Journal of Applied Ichthyology}, volume = {29}, number = {1}, pages = {71--81}, abstract = {The most commonly observed reproductive dysfunction in male fishes reared in captivity is reduction in sperm volume and quality. The Atlantic bluefin tuna Thunnus thynnus (Osteichthyes: Scombridae) is one of the few large pelagic and migratory marine fishes maintained in captivity with the purpose of establishing breeding populations to support an aquaculture industry. The objectives of the present study were to compare male germ cell proliferation and apoptosis between wild and captive individuals at two different phases of the spermatogenetic cycle, and to evaluate sperm motility characteristics of captive individuals. Histological observations were performed to analyze testicular activity, and germ cell proliferation and apoptosis were evaluated through the immunohistochemical detection of proliferating cell nuclear antigen (PCNA) and the terminal deoxynucleotidyl transferasemediated d'UTP nick end labeling (TUNEL) method, respectively. Computer-assisted sperm analysis (CASA) was used to evaluate sperm motility. Results showed that germ cell proliferation was delayed and germ cell apoptosis increased in captive animals relative to wild individuals. Sperm motility of samples obtained from captive individuals was anomalous, both in terms of motility duration and swimming efficiency. Thus it appears that rearing in captivity impairs male reproductive function through, at least, changes in germ cell proliferation and apoptosis. © 2012 Blackwell Verlag GmbH.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The most commonly observed reproductive dysfunction in male fishes reared in captivity is reduction in sperm volume and quality. The Atlantic bluefin tuna Thunnus thynnus (Osteichthyes: Scombridae) is one of the few large pelagic and migratory marine fishes maintained in captivity with the purpose of establishing breeding populations to support an aquaculture industry. The objectives of the present study were to compare male germ cell proliferation and apoptosis between wild and captive individuals at two different phases of the spermatogenetic cycle, and to evaluate sperm motility characteristics of captive individuals. Histological observations were performed to analyze testicular activity, and germ cell proliferation and apoptosis were evaluated through the immunohistochemical detection of proliferating cell nuclear antigen (PCNA) and the terminal deoxynucleotidyl transferasemediated d'UTP nick end labeling (TUNEL) method, respectively. Computer-assisted sperm analysis (CASA) was used to evaluate sperm motility. Results showed that germ cell proliferation was delayed and germ cell apoptosis increased in captive animals relative to wild individuals. Sperm motility of samples obtained from captive individuals was anomalous, both in terms of motility duration and swimming efficiency. Thus it appears that rearing in captivity impairs male reproductive function through, at least, changes in germ cell proliferation and apoptosis. © 2012 Blackwell Verlag GmbH. |
Sfakianakis, D G; Papadakis, I E; Papadaki, M; Sigelaki, I; Mylonas, C C Aquaculture, 412-413 , pp. 179–185, 2013, ISSN: 00448486. @article{sfakianakis_influence_2013, title = {Influence of rearing temperature during early life on sex differentiation, haemal lordosis and subsequent growth during the whole production cycle in European sea bass Dicentrarchus labrax}, author = {D G Sfakianakis and I E Papadakis and M Papadaki and I Sigelaki and C C Mylonas}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84881179660&doi=10.1016%2fj.aquaculture.2013.07.033&partnerID=40&md5=417cda13a14a81284d42c36155bb7bb9}, doi = {10.1016/j.aquaculture.2013.07.033}, issn = {00448486}, year = {2013}, date = {2013-01-01}, journal = {Aquaculture}, volume = {412-413}, pages = {179--185}, abstract = {The present study examined the influence of early-rearing temperature-which favors the development of male-dominant or female-dominant populations-in European sea bass Dicentrarchus labrax on haemal lordosis and growth performance until harvest time (mean body weight textgreater 400. g). European sea bass were reared at 15 or 20. °C from egg to metamorphosis ( . 17. mm in total length), which lasted for 66 and 55. days post spawning (dps), or 990 and 1100. °C-days, respectively. Thereafter, rearing until harvest time (715. dps) followed a common temperature regime, ranging between 14.5. °C in February and 26.5. °C in August. As expected from previous studies, the effect of early-life rearing temperature was significant on mean (± SEM) sex ratio (78 ± 2% females at 15. °C vs. 29 ± 2% females at 20. °C) and there was a highly significant (P textless 0.01) growth advantage in favor of the 20. °C fish at the end of the first year. However, there was no significant difference in body weight between the two temperature groups by harvest time, indicating the expression of compensatory growth in the 15. °C group. The mean occurrence of haemal lordosis incidence was evaluated using X-rays at the end of the nursery phase (145. dps) and was shown to be significantly higher in the 20. °C group (90 ± 0.4%) compared to the 15. °C group (41 ± 0.8%). The occurrence of haemal lordosis upon external image evaluation at harvest time decreased to 0% in the 15. °C group compared to 36 ± 7% in the 20. °C group. Almost half of these latter fish with haemal lordosis were considered unmarketable due to heavy deformation. These findings demonstrated that rearing European sea bass at low temperatures during early life can result in significant gains for aquaculture industry, through increases in female proportion-and therefore growth performance-and reductions in skeletal abnormalities. The study also demonstrated that even fish with heavy haemal lordosis could grow as well as normal fish, thus competing for food with normal fish and resulting in financial loss for the industry due to their unmarketability. © 2013 Elsevier B.V.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The present study examined the influence of early-rearing temperature-which favors the development of male-dominant or female-dominant populations-in European sea bass Dicentrarchus labrax on haemal lordosis and growth performance until harvest time (mean body weight textgreater 400. g). European sea bass were reared at 15 or 20. °C from egg to metamorphosis ( . 17. mm in total length), which lasted for 66 and 55. days post spawning (dps), or 990 and 1100. °C-days, respectively. Thereafter, rearing until harvest time (715. dps) followed a common temperature regime, ranging between 14.5. °C in February and 26.5. °C in August. As expected from previous studies, the effect of early-life rearing temperature was significant on mean (± SEM) sex ratio (78 ± 2% females at 15. °C vs. 29 ± 2% females at 20. °C) and there was a highly significant (P textless 0.01) growth advantage in favor of the 20. °C fish at the end of the first year. However, there was no significant difference in body weight between the two temperature groups by harvest time, indicating the expression of compensatory growth in the 15. °C group. The mean occurrence of haemal lordosis incidence was evaluated using X-rays at the end of the nursery phase (145. dps) and was shown to be significantly higher in the 20. °C group (90 ± 0.4%) compared to the 15. °C group (41 ± 0.8%). The occurrence of haemal lordosis upon external image evaluation at harvest time decreased to 0% in the 15. °C group compared to 36 ± 7% in the 20. °C group. Almost half of these latter fish with haemal lordosis were considered unmarketable due to heavy deformation. These findings demonstrated that rearing European sea bass at low temperatures during early life can result in significant gains for aquaculture industry, through increases in female proportion-and therefore growth performance-and reductions in skeletal abnormalities. The study also demonstrated that even fish with heavy haemal lordosis could grow as well as normal fish, thus competing for food with normal fish and resulting in financial loss for the industry due to their unmarketability. © 2013 Elsevier B.V. |
Mylonas, C C; Mitrizakis, N; Papadaki, M; Sigelaki, I Reproduction of hatchery-produced meagre Argyrosomus regius in captivity I. Description of the annual reproductive cycle Journal Article Aquaculture, 414-415 , pp. 309–317, 2013, ISSN: 00448486. @article{mylonas_reproduction_2013, title = {Reproduction of hatchery-produced meagre Argyrosomus regius in captivity I. Description of the annual reproductive cycle}, author = {C C Mylonas and N Mitrizakis and M Papadaki and I Sigelaki}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84886398444&doi=10.1016%2fj.aquaculture.2013.09.009&partnerID=40&md5=fc22bf7e18df3784b789a65fb143610b}, doi = {10.1016/j.aquaculture.2013.09.009}, issn = {00448486}, year = {2013}, date = {2013-01-01}, journal = {Aquaculture}, volume = {414-415}, pages = {309--317}, abstract = {The aim of the present study was to monitor the reproductive cycle of a hatchery-produced meagre Argyrosomus regius broodstock. Four-year-old fish of a mean weight (±SD) of 5.1±1.1kg for females (n=7) and 4.6±0.7kg for males (n=6), were maintained under simulated natural photo-thermal regime and sampled between November 2010 and July 2011. Vitellogenesis began in March, when the first increase in oocyte diameter was observed. Fully vitellogenic oocytes of mean (±SEM) diameter between 561±23 and 621±9μm were observed between April and June. Two of the seven females spawned spontaneously in June, producing six major spawns of 390,000-940,000 eggs per day with fertilization success >97%. Vitellogenesis was associated with relatively low levels of testosterone (T) ranging between mean values of 0.036±0.01ngml-1 and 0.207±0.07ngml-1, and of 17β-estradiol (E2) ranging between mean values of 0.194±0.09ngml-1 and 0.473±0.12ngml-1. Spermiation also began in March, but only 33% of the fish produced significant amounts of milt to allow sperm quality evaluations. In May 100% of the fish were spermiating, and in July spermiation ceased almost completely. No significant changes were observed during the spermiation period (March-June) in sperm concentration (mean ranged between 18.9 and 31.5×109szoaml-1) or initial sperm motility (mean ranged between 44 and 80%). The mean duration of motility (mean ranged between 0.78 and 1.27min) was also stable during the reproductive season, with the exception of a significant decrease in May. Mean plasma T and 11-ketotestosterone (11-KT) levels in male meagre increased gradually during the year, reaching their spermiation season peaks in March (0.818ng11-KTml-1) or in May (0.263ngTml-1). The study demonstrated that gametogenesis proceeds normally in hatchery-produced meagre and under the influence of relatively low levels of sex steroid hormones. Although spontaneous spawning was observed for the first time in meagre maintained in captivity (2 of 7 females), the study demonstrated also that oocyte maturation is sporadic and inconsistent, and reliable spawning could be obtained using only exogenous hormones. Furthermore, it was shown that females failing to undergo oocyte maturation, maintain their vitellogenic oocytes in a viable condition without significant atresia for a period of at least 2months (April-June). These oocytes could potentially be induced to undergo maturation, ovulation and spawning at any time during this "post-vitellogenesis" period. © 2013 Elsevier B.V.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The aim of the present study was to monitor the reproductive cycle of a hatchery-produced meagre Argyrosomus regius broodstock. Four-year-old fish of a mean weight (±SD) of 5.1±1.1kg for females (n=7) and 4.6±0.7kg for males (n=6), were maintained under simulated natural photo-thermal regime and sampled between November 2010 and July 2011. Vitellogenesis began in March, when the first increase in oocyte diameter was observed. Fully vitellogenic oocytes of mean (±SEM) diameter between 561±23 and 621±9μm were observed between April and June. Two of the seven females spawned spontaneously in June, producing six major spawns of 390,000-940,000 eggs per day with fertilization success >97%. Vitellogenesis was associated with relatively low levels of testosterone (T) ranging between mean values of 0.036±0.01ngml-1 and 0.207±0.07ngml-1, and of 17β-estradiol (E2) ranging between mean values of 0.194±0.09ngml-1 and 0.473±0.12ngml-1. Spermiation also began in March, but only 33% of the fish produced significant amounts of milt to allow sperm quality evaluations. In May 100% of the fish were spermiating, and in July spermiation ceased almost completely. No significant changes were observed during the spermiation period (March-June) in sperm concentration (mean ranged between 18.9 and 31.5×109szoaml-1) or initial sperm motility (mean ranged between 44 and 80%). The mean duration of motility (mean ranged between 0.78 and 1.27min) was also stable during the reproductive season, with the exception of a significant decrease in May. Mean plasma T and 11-ketotestosterone (11-KT) levels in male meagre increased gradually during the year, reaching their spermiation season peaks in March (0.818ng11-KTml-1) or in May (0.263ngTml-1). The study demonstrated that gametogenesis proceeds normally in hatchery-produced meagre and under the influence of relatively low levels of sex steroid hormones. Although spontaneous spawning was observed for the first time in meagre maintained in captivity (2 of 7 females), the study demonstrated also that oocyte maturation is sporadic and inconsistent, and reliable spawning could be obtained using only exogenous hormones. Furthermore, it was shown that females failing to undergo oocyte maturation, maintain their vitellogenic oocytes in a viable condition without significant atresia for a period of at least 2months (April-June). These oocytes could potentially be induced to undergo maturation, ovulation and spawning at any time during this "post-vitellogenesis" period. © 2013 Elsevier B.V. |
Mylonas, C C; Mitrizakis, N; Castaldo, C A; Cerviño, C P; Papadaki, M; Sigelaki, I Aquaculture, 414-415 , pp. 318 – 327, 2013. @article{mylonas_reproduction_2013-1, title = {Reproduction of hatchery-produced meagre Argyrosomus regius in captivity II. Hormonal induction of spawning and monitoring of spawning kinetics, egg production and egg quality}, author = {C C Mylonas and N Mitrizakis and C A Castaldo and C P Cerviño and M Papadaki and I Sigelaki}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84886377596&partnerID=40&md5=237d527a7e2831d820e80c1868708b9d}, year = {2013}, date = {2013-01-01}, journal = {Aquaculture}, volume = {414-415}, pages = {318 -- 327}, abstract = {The present study aimed at the development of an effective and efficient hormonal spawning induction method for meagre Argyrosomus regius, using controlled-release delivery systems loaded with gonadotropin-releasing hormone agonist (GnRHa). Three sets of spawning induction experiments were undertaken in the course of three years. In experiment 1, group spawnings were performed at different times during the reproductive period, in order to determine the most appropriate time for hormonal induction of spawning. Experiment 2 described in more detail the spawning kinetics of individual females induced to spawn at different times during the season, in order to obtain important information on spawning kinetics, batch fecundity and total fecundity in response to the hormonal treatment. In experiment 3, two similar broodstocks were used to obtain further production characteristics and monitor variations in egg/larval quality over the spawning period. The effective GnRHa doses used were 55-84μgGnRHakg-1 body weight in males and 46-92μgGnRHakg-1 in females. In general, successful spawning induction was achieved between early May and early June. Implantation with GnRHa induced spawning 2-3d after treatment and produced an average (±SD) of 12±5 spawns per broodstock or female over 3weeks, most of them over consecutive days. Batch fecundity was extremely variable (mean of 6631 to 104,409eggskg-1), with the largest batches occurring 3-4d after treatment, and very low fecundity after 1week from GnRHa treatment. As a result, the first 4 spawns of all spawning induction experiments constituted a mean of 75±13% of the total relative fecundity. Overall mean total relative fecundity was variable at 380,780±167,577eggskg-1. Evaluation of the ovaries after the cessation of spawning, demonstrated that the females still contained large numbers of oocytes in full vitellogenesis, and it is hypothesized that these fish could spawn further in response to a second GnRHa implantation. Fertilization success was very high in all spawning induction experiments, with the overall mean being 89±5%. Similarly, the produced eggs were of very high quality, based on the survival of the eggs during embryogenesis (>95%), hatching success (>99%) and larval survival 5d after egg collection (>87%), resulting in an overall larva survival of 73% of the total number of eggs spawned. These studies demonstrate that the GnRHa implants are an effective and efficient method for the induction of spawning in meagre, leading to the production of eggs of high fecundity and quality. © 2013 Elsevier B.V.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The present study aimed at the development of an effective and efficient hormonal spawning induction method for meagre Argyrosomus regius, using controlled-release delivery systems loaded with gonadotropin-releasing hormone agonist (GnRHa). Three sets of spawning induction experiments were undertaken in the course of three years. In experiment 1, group spawnings were performed at different times during the reproductive period, in order to determine the most appropriate time for hormonal induction of spawning. Experiment 2 described in more detail the spawning kinetics of individual females induced to spawn at different times during the season, in order to obtain important information on spawning kinetics, batch fecundity and total fecundity in response to the hormonal treatment. In experiment 3, two similar broodstocks were used to obtain further production characteristics and monitor variations in egg/larval quality over the spawning period. The effective GnRHa doses used were 55-84μgGnRHakg-1 body weight in males and 46-92μgGnRHakg-1 in females. In general, successful spawning induction was achieved between early May and early June. Implantation with GnRHa induced spawning 2-3d after treatment and produced an average (±SD) of 12±5 spawns per broodstock or female over 3weeks, most of them over consecutive days. Batch fecundity was extremely variable (mean of 6631 to 104,409eggskg-1), with the largest batches occurring 3-4d after treatment, and very low fecundity after 1week from GnRHa treatment. As a result, the first 4 spawns of all spawning induction experiments constituted a mean of 75±13% of the total relative fecundity. Overall mean total relative fecundity was variable at 380,780±167,577eggskg-1. Evaluation of the ovaries after the cessation of spawning, demonstrated that the females still contained large numbers of oocytes in full vitellogenesis, and it is hypothesized that these fish could spawn further in response to a second GnRHa implantation. Fertilization success was very high in all spawning induction experiments, with the overall mean being 89±5%. Similarly, the produced eggs were of very high quality, based on the survival of the eggs during embryogenesis (>95%), hatching success (>99%) and larval survival 5d after egg collection (>87%), resulting in an overall larva survival of 73% of the total number of eggs spawned. These studies demonstrate that the GnRHa implants are an effective and efficient method for the induction of spawning in meagre, leading to the production of eggs of high fecundity and quality. © 2013 Elsevier B.V. |
2012 |
Alavi, S M H; Hatef, A; Mylonas, C C; Gela, D; Papadaki, M; Rodina, M; Kašpar, V; Pšenička, M; Podhorec, P; Linhart, O Sperm characteristics and androgens in Acipenser ruthenus after induction of spermiation by carp pituitary extract or GnRHa implants Journal Article Fish Physiology and Biochemistry, 38 (6), pp. 1655–1666, 2012, ISSN: 09201742. @article{alavi_sperm_2012, title = {Sperm characteristics and androgens in Acipenser ruthenus after induction of spermiation by carp pituitary extract or GnRHa implants}, author = {S M H Alavi and A Hatef and C C Mylonas and D Gela and M Papadaki and M Rodina and V Kašpar and M Pšenička and P Podhorec and O Linhart}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84869128817&doi=10.1007%2fs10695-012-9662-9&partnerID=40&md5=0dd912dc379a6d91d765f370b929505f}, doi = {10.1007/s10695-012-9662-9}, issn = {09201742}, year = {2012}, date = {2012-01-01}, journal = {Fish Physiology and Biochemistry}, volume = {38}, number = {6}, pages = {1655--1666}, abstract = {Spermiation and changes in androgen (testosterone, T and 11-ketotestosterone, 11-KT) levels were studied in sterlet (Acipenser ruthenus) treated with GnRH agonist implants (dAla6-Pro9-LHRHa) at 25 and 75 μg kg-1 b. w. and compared with those males treated with 4 mg kg-1 b. w. of carp pituitary extract (CPE) and 3 pellets of Ovopel kg-1 b. w., which contains dAla6-Pro9NEt-mGnRH and metoclopramide. Sperm quality (sperm mass, spermatozoa concentration and sperm motility and velocity) was evaluated 24, 48 and 72 h after hormonal treatments. Males did not release sperm in the control group injected with physiological solution, while sperm could not be collected 7 days after treatments in all hormonally treated groups. Spermiation rates were 100 % in the CPE and Ovopel groups and 25-50 % in the GnRHa-treated groups. Sperm production was significantly lower in the GnRHa-treated groups than in the CPE and Ovopel groups and decreased 72 h after hormonal treatment. Sperm motility and velocity were higher in the Ovopel and GnRHa (75 μg) groups compared to the CPE and GnRHa (25 μg) groups and decreased 72 h after hormonal treatment. Androgens were only affected in spermiating males and changed in the Ovopel and GnRHa (75 μg) after hormonal treatment. Significant correlations were observed between sperm production, sperm motility and sperm velocity, but not androgens. The present study suggests involvement of dopamine in sturgeon spawning. Additionally, better sperm quality observed in the Ovopel group and particularly sperm motility in the GnRHa (75 μg) suggests enhancement of sperm quality in sturgeon treated with GnRHa. Therefore, further study is needed to induce fully spermiation using GnRHa implants in combination with a dopamine inhibitor. © 2012 Springer Science+Business Media B.V.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Spermiation and changes in androgen (testosterone, T and 11-ketotestosterone, 11-KT) levels were studied in sterlet (Acipenser ruthenus) treated with GnRH agonist implants (dAla6-Pro9-LHRHa) at 25 and 75 μg kg-1 b. w. and compared with those males treated with 4 mg kg-1 b. w. of carp pituitary extract (CPE) and 3 pellets of Ovopel kg-1 b. w., which contains dAla6-Pro9NEt-mGnRH and metoclopramide. Sperm quality (sperm mass, spermatozoa concentration and sperm motility and velocity) was evaluated 24, 48 and 72 h after hormonal treatments. Males did not release sperm in the control group injected with physiological solution, while sperm could not be collected 7 days after treatments in all hormonally treated groups. Spermiation rates were 100 % in the CPE and Ovopel groups and 25-50 % in the GnRHa-treated groups. Sperm production was significantly lower in the GnRHa-treated groups than in the CPE and Ovopel groups and decreased 72 h after hormonal treatment. Sperm motility and velocity were higher in the Ovopel and GnRHa (75 μg) groups compared to the CPE and GnRHa (25 μg) groups and decreased 72 h after hormonal treatment. Androgens were only affected in spermiating males and changed in the Ovopel and GnRHa (75 μg) after hormonal treatment. Significant correlations were observed between sperm production, sperm motility and sperm velocity, but not androgens. The present study suggests involvement of dopamine in sturgeon spawning. Additionally, better sperm quality observed in the Ovopel group and particularly sperm motility in the GnRHa (75 μg) suggests enhancement of sperm quality in sturgeon treated with GnRHa. Therefore, further study is needed to induce fully spermiation using GnRHa implants in combination with a dopamine inhibitor. © 2012 Springer Science+Business Media B.V. |
2011 |
Katharios, P; Kokkari, K; Papadaki, M; Papandroulakis, N Systemic granulomas in cultured meagre, Argyrosomus regius. Inproceedings pp. 537–538, European Aquaculture Society, Rhodes, Greece, 2011, (Publication Title: Aquaculture Europe 11 Type: Conference Paper). @inproceedings{katharios_systemic_2011, title = {Systemic granulomas in cultured meagre, Argyrosomus regius.}, author = {P Katharios and K Kokkari and M Papadaki and N Papandroulakis}, year = {2011}, date = {2011-10-01}, pages = {537--538}, publisher = {European Aquaculture Society}, address = {Rhodes, Greece}, note = {Publication Title: Aquaculture Europe 11 Type: Conference Paper}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Chatzifotis, S; Papadaki, M; Despoti, S; Roufidou, C; Antonopoulou, E Aquaculture, 316 (1-4), pp. 53–59, 2011, ISSN: 00448486. @article{chatzifotis_effect_2011, title = {Effect of starvation and re-feeding on reproductive indices, body weight, plasma metabolites and oxidative enzymes of sea bass (Dicentrarchus labrax)}, author = {S Chatzifotis and M Papadaki and S Despoti and C Roufidou and E Antonopoulou}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-79955131847&doi=10.1016%2fj.aquaculture.2011.02.044&partnerID=40&md5=8a3a15311e061e5ee4b2fe8624820b95}, doi = {10.1016/j.aquaculture.2011.02.044}, issn = {00448486}, year = {2011}, date = {2011-01-01}, journal = {Aquaculture}, volume = {316}, number = {1-4}, pages = {53--59}, abstract = {Feed management is an important factor for successful aquaculture, especially when it affects gonad maturation. In this context, the present study evaluates the effects of long term starvation (1F-3S: one-month feeding - three-month starvation) and starvation/re-feeding (2S-2F: two-month starvation - two-month re-feeding) on gonad maturation, hematological/biochemical indices and proximate composition of liver and muscle of vitelogenic sea bass. In males, all the fish in the control group (4F-0S: four-month feeding - zero-month starvation) reached the maturity stage S2 (Mature), while only 33% and 75% reached that stage in the 1F-3S and 2S-2F groups, respectively. In females, the percentages of immature gonads were 80%, 25% and 50% for the groups 1F-3S, 2S-2F and 4F-0S respectively, while the percentages of the fish which reached the stage of vitellogenesis were 20%, 75% and 50% for the same groups. The concentration of glucose and lactate in plasma was not affected by starvation or re-feeding. On the contrary, triglycerides, phospholipids and total lipids of group 1F-3S decreased significantly, whereas cholesterol did not differ compared to the control group. In the 2S-2F group, total lipids and cholesterol were also significantly decreased while triglycerides and phospholipids were not altered. Proximate composition analysis in the liver showed that long term starvation (1F-3S) led to a significant reduction of crude lipid and ash, compared to the 4F-0S and 2S-2F groups. In contrast, crude protein concentration in the liver was significantly increased in 1F-3S group compared to 4F-0S and 2S-2F groups. In white muscle a significant reduction of crude lipids was detected in the 1F-3S and 2S-2F groups, while no significant changes were observed in crude protein, ash and moisture concentrations. The enzymatic activities of lactate dehydrogenase (L-LDH), citrate synthase (CS) and 3-hydroxyacyl CoA dehydrogenase (HOAD) were significantly increased in the liver of 1F-3S fish, whereas in red muscle both HOAD and CS were significantly decreased in both 1F-3S and 2S-2F groups. Overall our results indicate that a 2. month starvation and 2. month re-feeding period during vitellogenesis reduces GSI and maturity stage in male sea bass and affect the levels of biochemical blood indices and the activities of certain enzymes of the intermediary metabolism. © 2011 Elsevier B.V.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Feed management is an important factor for successful aquaculture, especially when it affects gonad maturation. In this context, the present study evaluates the effects of long term starvation (1F-3S: one-month feeding - three-month starvation) and starvation/re-feeding (2S-2F: two-month starvation - two-month re-feeding) on gonad maturation, hematological/biochemical indices and proximate composition of liver and muscle of vitelogenic sea bass. In males, all the fish in the control group (4F-0S: four-month feeding - zero-month starvation) reached the maturity stage S2 (Mature), while only 33% and 75% reached that stage in the 1F-3S and 2S-2F groups, respectively. In females, the percentages of immature gonads were 80%, 25% and 50% for the groups 1F-3S, 2S-2F and 4F-0S respectively, while the percentages of the fish which reached the stage of vitellogenesis were 20%, 75% and 50% for the same groups. The concentration of glucose and lactate in plasma was not affected by starvation or re-feeding. On the contrary, triglycerides, phospholipids and total lipids of group 1F-3S decreased significantly, whereas cholesterol did not differ compared to the control group. In the 2S-2F group, total lipids and cholesterol were also significantly decreased while triglycerides and phospholipids were not altered. Proximate composition analysis in the liver showed that long term starvation (1F-3S) led to a significant reduction of crude lipid and ash, compared to the 4F-0S and 2S-2F groups. In contrast, crude protein concentration in the liver was significantly increased in 1F-3S group compared to 4F-0S and 2S-2F groups. In white muscle a significant reduction of crude lipids was detected in the 1F-3S and 2S-2F groups, while no significant changes were observed in crude protein, ash and moisture concentrations. The enzymatic activities of lactate dehydrogenase (L-LDH), citrate synthase (CS) and 3-hydroxyacyl CoA dehydrogenase (HOAD) were significantly increased in the liver of 1F-3S fish, whereas in red muscle both HOAD and CS were significantly decreased in both 1F-3S and 2S-2F groups. Overall our results indicate that a 2. month starvation and 2. month re-feeding period during vitellogenesis reduces GSI and maturity stage in male sea bass and affect the levels of biochemical blood indices and the activities of certain enzymes of the intermediary metabolism. © 2011 Elsevier B.V. |
Katharios, P; Papadaki, M; Ternengo, S; Kantham, P K; Zeri, C; Petraki, P E; Divanach, P Chronic ulcerative dermatopathy in cultured marine fishes. Comparative study in sharpsnout sea bream, Diplodus puntazzo (Walbaum) Journal Article Journal of Fish Diseases, 34 (6), pp. 459–474, 2011, ISSN: 01407775. @article{katharios_chronic_2011, title = {Chronic ulcerative dermatopathy in cultured marine fishes. Comparative study in sharpsnout sea bream, Diplodus puntazzo (Walbaum)}, author = {P Katharios and M Papadaki and S Ternengo and P K Kantham and C Zeri and P E Petraki and P Divanach}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-79955640274&doi=10.1111%2fj.1365-2761.2011.01257.x&partnerID=40&md5=da9a133e20c28b1376b9ba550b57d497}, doi = {10.1111/j.1365-2761.2011.01257.x}, issn = {01407775}, year = {2011}, date = {2011-01-01}, journal = {Journal of Fish Diseases}, volume = {34}, number = {6}, pages = {459--474}, abstract = {Chronic ulcerative dermatopathy (CUD) also known as chronic erosive dermatopathy, hole-in-the-head, head and lateral line erosion syndrome (HLLE) and lateral line depigmentation (LLD) is a chronic disease of unknown aetiology that affects the lateral line canals of the head and the trunk of various fish species. It has been described only in freshwater species although there are reports that it also affects marine fish. Here, we describe the disease in cultured sharpsnout sea bream using histology and scanning electron microscopy and identify several marine species as CUD sensitive. The results of this study correlate the development of the disease with the use of borehole water, indicating that the aetiology is probably associated with water quality rather than nutritional imbalance or infectious agents. © 2011 Blackwell Publishing Ltd.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Chronic ulcerative dermatopathy (CUD) also known as chronic erosive dermatopathy, hole-in-the-head, head and lateral line erosion syndrome (HLLE) and lateral line depigmentation (LLD) is a chronic disease of unknown aetiology that affects the lateral line canals of the head and the trunk of various fish species. It has been described only in freshwater species although there are reports that it also affects marine fish. Here, we describe the disease in cultured sharpsnout sea bream using histology and scanning electron microscopy and identify several marine species as CUD sensitive. The results of this study correlate the development of the disease with the use of borehole water, indicating that the aetiology is probably associated with water quality rather than nutritional imbalance or infectious agents. © 2011 Blackwell Publishing Ltd. |
2010 |
Suquet, M; Cosson, J; Gándara, De La F; Mylonas, C C; Papadaki, M; Lallemant, S; Fauvel, C Sperm features of captive Atlantic bluefin tuna (Thunnus thynnus) Journal Article Journal of Applied Ichthyology, 26 (5), pp. 775–778, 2010, ISSN: 01758659. @article{suquet_sperm_2010, title = {Sperm features of captive Atlantic bluefin tuna (Thunnus thynnus)}, author = {M Suquet and J Cosson and F De La Gándara and C C Mylonas and M Papadaki and S Lallemant and C Fauvel}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-78650452401&doi=10.1111%2fj.1439-0426.2010.01533.x&partnerID=40&md5=5016c29a26780365dae2b92fd4c31683}, doi = {10.1111/j.1439-0426.2010.01533.x}, issn = {01758659}, year = {2010}, date = {2010-01-01}, journal = {Journal of Applied Ichthyology}, volume = {26}, number = {5}, pages = {775--778}, abstract = {The present study aimed to establish some basic characteristics of Atlantic bluefin tuna sperm from captive mature males, treated or untreated by gonadotropin releasing hormones agonist (GnRHa). Intratesticular milt was collected from treated and untreated fish (mean weight±SD: 122.9±29.2-kg}, keywords = {}, pubstate = {published}, tppubtype = {article} } The present study aimed to establish some basic characteristics of Atlantic bluefin tuna sperm from captive mature males, treated or untreated by gonadotropin releasing hormones agonist (GnRHa). Intratesticular milt was collected from treated and untreated fish (mean weight±SD: 122.9±29.2-kg |
2008 |
Katharios, P; Papadaki, M; Papandroulakis, N; Divanach, P Severe mortality in mesocosm-reared sharpsnout sea bream Diplodus puntazzo larvae due to epitheliocystis infection Journal Article Diseases of Aquatic Organisms, 82 (1), pp. 55–60, 2008, ISSN: 01775103. @article{katharios_severe_2008, title = {Severe mortality in mesocosm-reared sharpsnout sea bream Diplodus puntazzo larvae due to epitheliocystis infection}, author = {P Katharios and M Papadaki and N Papandroulakis and P Divanach}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-56649123097&doi=10.3354%2fdao01968&partnerID=40&md5=1c652a653ce36b0e7ae3f6a7b9d1aff6}, doi = {10.3354/dao01968}, issn = {01775103}, year = {2008}, date = {2008-01-01}, journal = {Diseases of Aquatic Organisms}, volume = {82}, number = {1}, pages = {55--60}, abstract = {This paper describes severe mortalities recorded in sharpsnout sea bream Diplodus puntazzo larvae reared in mesocosms. The mortalities were attributed to epitheliocystis infection. The pathology associated with the disease is described using histological techniques. Microscopical examination showed a massive infection of the skin, fins, and oral cavity, with impaired feeding, respiration, and osmoregulation being the most likely cause of death. This is the first report of epitheliocystis disease in sharpsnout sea bream and in fish at such an early developmental stage. © Inter-Research 2008.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This paper describes severe mortalities recorded in sharpsnout sea bream Diplodus puntazzo larvae reared in mesocosms. The mortalities were attributed to epitheliocystis infection. The pathology associated with the disease is described using histological techniques. Microscopical examination showed a massive infection of the skin, fins, and oral cavity, with impaired feeding, respiration, and osmoregulation being the most likely cause of death. This is the first report of epitheliocystis disease in sharpsnout sea bream and in fish at such an early developmental stage. © Inter-Research 2008. |
Blázquez, M; González, A; Papadaki, M; Mylonas, C; Piferrer, F General and Comparative Endocrinology, 158 (1), pp. 95–101, 2008, ISSN: 00166480, (Publisher: Academic Press Inc.). @article{blazquez_sex-related_2008, title = {Sex-related changes in estrogen receptors and aromatase gene expression and enzymatic activity during early development and sex differentiation in the European sea bass (Dicentrarchus labrax)}, author = {M Blázquez and A González and M Papadaki and C Mylonas and F Piferrer}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-47749115671&doi=10.1016%2fj.ygcen.2008.06.001&partnerID=40&md5=de231a70456b1272ea82f3d813879364}, doi = {10.1016/j.ygcen.2008.06.001}, issn = {00166480}, year = {2008}, date = {2008-01-01}, journal = {General and Comparative Endocrinology}, volume = {158}, number = {1}, pages = {95--101}, abstract = {The present study addresses the role of aromatase and estrogen receptors in sex differentiation and development. With this purpose, a sea bass female- and a male-dominant group were obtained by successive size gradings since in this species females are already larger than males at the time of sex differentiation. Changes in cyp19a and cyp19b gene expression and enzymatic activity were monitored by a validated real-time PCR and a tritiated water assay, respectively, during early development and sex differentiation. Changes in mRNA expression of estrogen receptors, both erb1 and erb2, were also assessed during this period. Results show clear sex-related differences in cyp19a gene expression and enzymatic activity in gonads, with females exhibiting significantly higher levels than males at 150 days post hatching (DPH), when histological signs of sex differentiation were evident. cyp19b gene expression and activity in brain were detectable during early ontogenesis at 50 DPH but no clear sex-related differences were observed. Both erb1 and erb2 showed higher gene expression levels in testis than in ovaries around 200-250 DPH, corresponding with the time of testicular differentiation and precocious male maturation, but no sex-related differences were found in the brain. Together these results indicate that in the European sea bass high expression levels of cyp19a are associated with ovarian differentiation and thus cyp19a can be considered as a suitable molecular marker of ovarian differentiation. However, the involvement of cyp19b in sex differentiation cannot be concluded. In addition, the higher levels of erb1 and erb2 in males versus females during sex differentiation, coinciding with precocious male maturation in the sea bass, suggest an important role for these receptors in testicular development and maturation. © 2008 Elsevier Inc. All rights reserved.}, note = {Publisher: Academic Press Inc.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The present study addresses the role of aromatase and estrogen receptors in sex differentiation and development. With this purpose, a sea bass female- and a male-dominant group were obtained by successive size gradings since in this species females are already larger than males at the time of sex differentiation. Changes in cyp19a and cyp19b gene expression and enzymatic activity were monitored by a validated real-time PCR and a tritiated water assay, respectively, during early development and sex differentiation. Changes in mRNA expression of estrogen receptors, both erb1 and erb2, were also assessed during this period. Results show clear sex-related differences in cyp19a gene expression and enzymatic activity in gonads, with females exhibiting significantly higher levels than males at 150 days post hatching (DPH), when histological signs of sex differentiation were evident. cyp19b gene expression and activity in brain were detectable during early ontogenesis at 50 DPH but no clear sex-related differences were observed. Both erb1 and erb2 showed higher gene expression levels in testis than in ovaries around 200-250 DPH, corresponding with the time of testicular differentiation and precocious male maturation, but no sex-related differences were found in the brain. Together these results indicate that in the European sea bass high expression levels of cyp19a are associated with ovarian differentiation and thus cyp19a can be considered as a suitable molecular marker of ovarian differentiation. However, the involvement of cyp19b in sex differentiation cannot be concluded. In addition, the higher levels of erb1 and erb2 in males versus females during sex differentiation, coinciding with precocious male maturation in the sea bass, suggest an important role for these receptors in testicular development and maturation. © 2008 Elsevier Inc. All rights reserved. |
Papadaki, M; Papadopoulou, M; Siggelaki, I; Mylonas, C C Egg and sperm production and quality of sharpsnout sea bream (Diplodus puntazzo) in captivity Journal Article Aquaculture, 276 (1-4), pp. 187–197, 2008, ISSN: 00448486. @article{papadaki_egg_2008, title = {Egg and sperm production and quality of sharpsnout sea bream (Diplodus puntazzo) in captivity}, author = {M Papadaki and M Papadopoulou and I Siggelaki and C C Mylonas}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-41549160104&doi=10.1016%2fj.aquaculture.2008.01.033&partnerID=40&md5=be9ddc2c84556c6f70f1ec0d752baef9}, doi = {10.1016/j.aquaculture.2008.01.033}, issn = {00448486}, year = {2008}, date = {2008-01-01}, journal = {Aquaculture}, volume = {276}, number = {1-4}, pages = {187--197}, abstract = {Egg production from captive-reared sharpsnout sea bream (Diplodus puntazzo) was monitored during the spawning seasons of 2003 to 2005, and sperm production during 2003. Spawning took place between September and December under water temperatures of 21.0-18.5 °C. Daily fecundity varied without a consistent trend and peak egg production occurred in October. Mean (± S.E.M.) number of spawning days per month was 20 ± 3 in 2003, and 14 ± 3 in 2004 and 2005. A significant (ANOVA, DNMR, P < 0.01) drop was observed in mean total annual relative fecundity from 4.9 ± 0.08 million eggs kg- 1 female body weight in 2003, to 2.4 ± 0.07 million eggs kg- 1 in 2004 and 2005. Mean monthly fertilization success also dropped significantly from 81 ± 1% in 2003 to 76 ± 2% in 2004 and 78 ± 2% in 2005. Annual hatching success did not vary significantly and was around 86 ± 2%. Finally, 5 day larval survival decreased significantly from 85 ± 2% in 2003 to 44 ± 3% in 2004. The first spermiating males were found in August and sperm production continued until December. Mean total volume of expressible sperm was maximal in November (3 ± 1 ml kg- 1) and the gonadosomatic index (GSI) ranged between 0.6 and 2.0% in spermiating fish, reaching its peak in September-November. Sperm motility (%) remained unchanged during the season, whereas motility duration (6.2 ± 1.7 min) and sperm density (2.7 ± 0.2 × 1010 spermatozoa ml- 1) peaked in October. Mean sperm survival ranged between 9 and 13 days during most of the spawning season, and decreased significantly to 5 days in December. The study suggests that egg production is stable for the first 3 months of the spawning season, with relatively unchanged egg quality. On the contrary, sperm production and quality peaks in the middle of the reproductive season in October. © 2008 Elsevier B.V. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Egg production from captive-reared sharpsnout sea bream (Diplodus puntazzo) was monitored during the spawning seasons of 2003 to 2005, and sperm production during 2003. Spawning took place between September and December under water temperatures of 21.0-18.5 °C. Daily fecundity varied without a consistent trend and peak egg production occurred in October. Mean (± S.E.M.) number of spawning days per month was 20 ± 3 in 2003, and 14 ± 3 in 2004 and 2005. A significant (ANOVA, DNMR, P < 0.01) drop was observed in mean total annual relative fecundity from 4.9 ± 0.08 million eggs kg- 1 female body weight in 2003, to 2.4 ± 0.07 million eggs kg- 1 in 2004 and 2005. Mean monthly fertilization success also dropped significantly from 81 ± 1% in 2003 to 76 ± 2% in 2004 and 78 ± 2% in 2005. Annual hatching success did not vary significantly and was around 86 ± 2%. Finally, 5 day larval survival decreased significantly from 85 ± 2% in 2003 to 44 ± 3% in 2004. The first spermiating males were found in August and sperm production continued until December. Mean total volume of expressible sperm was maximal in November (3 ± 1 ml kg- 1) and the gonadosomatic index (GSI) ranged between 0.6 and 2.0% in spermiating fish, reaching its peak in September-November. Sperm motility (%) remained unchanged during the season, whereas motility duration (6.2 ± 1.7 min) and sperm density (2.7 ± 0.2 × 1010 spermatozoa ml- 1) peaked in October. Mean sperm survival ranged between 9 and 13 days during most of the spawning season, and decreased significantly to 5 days in December. The study suggests that egg production is stable for the first 3 months of the spawning season, with relatively unchanged egg quality. On the contrary, sperm production and quality peaks in the middle of the reproductive season in October. © 2008 Elsevier B.V. All rights reserved. |
Katharios, P; Papandroulakis, N; Papadaki, M; Syggelaki, E; Tzamarias, D; Gounalaki, N; Divanach, P Pseudomonas putida infection in captive wreckfish Polyprion americanus. A case report. Inproceedings Aquaculture Europe 08, pp. 307, European Aquacultrure Society, Krakow, Poland, 2008, (Backup Publisher: European Aquacultrure Society). @inproceedings{katharios_pseudomonas_2008, title = {Pseudomonas putida infection in captive wreckfish Polyprion americanus. A case report.}, author = {P Katharios and N Papandroulakis and M Papadaki and E Syggelaki and D Tzamarias and N Gounalaki and P Divanach}, year = {2008}, date = {2008-01-01}, booktitle = {Aquaculture Europe 08}, pages = {307}, publisher = {European Aquacultrure Society}, address = {Krakow, Poland}, note = {Backup Publisher: European Aquacultrure Society}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
2007 |
Mylonas, C C; Bridges, C; Gordin, H; Ríos, A B; García, A; Gándara, De La F; Fauvel, C; Suquet, M; Medina, A; Papadaki, M; Heinisch, G; Metrio, De G; Corriero, A; Vassallo-Agius, R; Guzmán, J -M; Mañanos, E; Zohar, Y Reviews in Fisheries Science, 15 (3), pp. 183–210, 2007, ISSN: 10641262. @article{mylonas_preparation_2007, title = {Preparation and administration of gonadotropin-releasing hormone agonist (GnRHa) implants for the artificial control of reproductive maturation in captive-reared Atlantic bluefin tuna (Thunnus thynnus thynnus)}, author = {C C Mylonas and C Bridges and H Gordin and A B Ríos and A García and F De La Gándara and C Fauvel and M Suquet and A Medina and M Papadaki and G Heinisch and G De Metrio and A Corriero and R Vassallo-Agius and J -M Guzmán and E Mañanos and Y Zohar}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-35648987213&doi=10.1080%2f10641260701484572&partnerID=40&md5=e9c5bc33d2bd695220a31847ed892503}, doi = {10.1080/10641260701484572}, issn = {10641262}, year = {2007}, date = {2007-01-01}, journal = {Reviews in Fisheries Science}, volume = {15}, number = {3}, pages = {183--210}, abstract = {Mature migrating Atlantic bluefin tuna (Thunnus thynnus thynnus) were captured in the Mediterranean Sea with a purse seine and reared in floating cages for 2 to 3 years. During the natural spawning period (June-July) of two consecutive years, fish were randomly implanted underwater with a controlled-release delivery system (implant) loaded with gonadotropin-releasing hormone agonist (GnRHa), in order to induce final oocyte maturation (FOM), ovulation/spermiation, and spawning. At the time of sampling, males were significantly larger than females (ANOVA, P 0.001), having a mean ( SE) fork length and body weight of 190 3 cm and 122 5 kg, compared to 176 3 cm and 94 4 kg of females, respectively. All fish were reproductively mature, with their age ranging between 5 and 12 years and males being a year older, on average. After GnRHa implantation, fish were monitored for spawning and the release of eggs, and were sacrificed at different times after hormone treatment in order to examine the progressive effect of the treatment on gonad maturation. The in vitro GnRHa release from the produced implants was maximal during the first 2 d, with a mean ( SE) release of 525 166 g GnRHa implant-1 day-1. The plasma GnRHa profile in vivo reflected the release in vitro, and statistically significant elevations in plasma GnRHa levels were measured until 7 d after treatment (ANOVA, P 0.01). The underwater implantation procedure was improved between 2004 and 2005, requiring an average ( SD) of 3.1 1.4 min for each fish, and was 64 and 84% successful in 2004 and 2005, respectively. There were no differences between the histological appearance of the testes of GnRHa-treated and control males, and almost all of them contained intra-testicular spermatozoa. However, the proportion of spermiating control males (n = 17) was only 12% compared to 26% for the GnRHa-implanted males (n = 19). Also, there were no differences between controls and GnRHa-implanted fish in sperm concentration, initial spermatozoa motility, or duration of forward motility, which ranged between 29.02-48.54 1010 spermatozoa ml-1, 58-63% and 8-9 min, respectively. Final oocyte maturation (FOM) and post-ovulatory follicles (POFs) occurred in 63% and 88%, respectively, of the GnRHa implanted females (n = 16), compared to 0% and 21%, respectively, of the control females (n = 14). In addition, two GnRHa-implanted females in 2005 were found to be ovulated at the time of sacrifice, and their eggs were fertilized in vitro with sperm from spermiating males, which resulted in viable embryos and larvae. Finally, although spawning was not observed, fertilized eggs were collected from the cages. Larvae produced from these eggs were identified as Atlantic bluefin tuna, demonstrating that the present GnRHa implantation method can be used to induce FOM, ovulation/spermiation, and spawning in captive-reared Atlantic bluefin tuna. Copyright © Taylor & Francis Group, LLC.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Mature migrating Atlantic bluefin tuna (Thunnus thynnus thynnus) were captured in the Mediterranean Sea with a purse seine and reared in floating cages for 2 to 3 years. During the natural spawning period (June-July) of two consecutive years, fish were randomly implanted underwater with a controlled-release delivery system (implant) loaded with gonadotropin-releasing hormone agonist (GnRHa), in order to induce final oocyte maturation (FOM), ovulation/spermiation, and spawning. At the time of sampling, males were significantly larger than females (ANOVA, P 0.001), having a mean ( SE) fork length and body weight of 190 3 cm and 122 5 kg, compared to 176 3 cm and 94 4 kg of females, respectively. All fish were reproductively mature, with their age ranging between 5 and 12 years and males being a year older, on average. After GnRHa implantation, fish were monitored for spawning and the release of eggs, and were sacrificed at different times after hormone treatment in order to examine the progressive effect of the treatment on gonad maturation. The in vitro GnRHa release from the produced implants was maximal during the first 2 d, with a mean ( SE) release of 525 166 g GnRHa implant-1 day-1. The plasma GnRHa profile in vivo reflected the release in vitro, and statistically significant elevations in plasma GnRHa levels were measured until 7 d after treatment (ANOVA, P 0.01). The underwater implantation procedure was improved between 2004 and 2005, requiring an average ( SD) of 3.1 1.4 min for each fish, and was 64 and 84% successful in 2004 and 2005, respectively. There were no differences between the histological appearance of the testes of GnRHa-treated and control males, and almost all of them contained intra-testicular spermatozoa. However, the proportion of spermiating control males (n = 17) was only 12% compared to 26% for the GnRHa-implanted males (n = 19). Also, there were no differences between controls and GnRHa-implanted fish in sperm concentration, initial spermatozoa motility, or duration of forward motility, which ranged between 29.02-48.54 1010 spermatozoa ml-1, 58-63% and 8-9 min, respectively. Final oocyte maturation (FOM) and post-ovulatory follicles (POFs) occurred in 63% and 88%, respectively, of the GnRHa implanted females (n = 16), compared to 0% and 21%, respectively, of the control females (n = 14). In addition, two GnRHa-implanted females in 2005 were found to be ovulated at the time of sacrifice, and their eggs were fertilized in vitro with sperm from spermiating males, which resulted in viable embryos and larvae. Finally, although spawning was not observed, fertilized eggs were collected from the cages. Larvae produced from these eggs were identified as Atlantic bluefin tuna, demonstrating that the present GnRHa implantation method can be used to induce FOM, ovulation/spermiation, and spawning in captive-reared Atlantic bluefin tuna. Copyright © Taylor & Francis Group, LLC. |
2006 |
Sarter, K; Papadaki, M; Zanuy, S; Mylonas, C C Aquaculture, 256 (1-4), pp. 443–456, 2006, ISSN: 00448486. @article{sarter_permanent_2006, title = {Permanent sex inversion in 1-year-old juveniles of the protogynous dusky grouper (Epinephelus marginatus) using controlled-release 17α-methyltestosterone implants}, author = {K Sarter and M Papadaki and S Zanuy and C C Mylonas}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-33646896490&doi=10.1016%2fj.aquaculture.2006.01.034&partnerID=40&md5=fae7d76571a7060e8182bf08f6c00e7e}, doi = {10.1016/j.aquaculture.2006.01.034}, issn = {00448486}, year = {2006}, date = {2006-01-01}, journal = {Aquaculture}, volume = {256}, number = {1-4}, pages = {443--456}, abstract = {Long-term treatments (April-June 2004) with 17α-methyltestosterone (MT) and/or human chorionic gonadotropin (hCG) were used to induce precocious sex change in 1-year-old juveniles (mean ± SD body weight of 131 ± 25 g) of the protogynous dusky grouper (Epinephelus marginatus). The MT treatment was given once a month using controlled-release implants (1.5 mg per implant, ∼11 mg kg- 1 body weight), whereas hCG was injected intramuscularly once a month (MT/hCG group) or every 2 weeks (hCG group). In vitro mean (± SEM) daily and total MT release from the implants was 22.6 ± 5.4 μg day- 1 implant- 1 and 686 ± 113 μg implant- 1, respectively. In vivo, plasma MT levels of European sea bas (Dicentrarchus labrax) used as model fish (203 ± 41 g body weight) and given a single MT implant were 18.5 ± 0.5 ng ml- 1 one day after implantation, declined to 9.6 ± 2.7 ng ml- 1 by day 11 and remained stable between 7.9 and 5.5 ng ml- 1 until day 32. Plasma MT levels were significantly elevated (2-way ANOVA, P < 0.01) in dusky grouper juveniles in response to the MT treatment, both 6 and 12 weeks after beginning the treatment. On the contrary, no significant differences (2-way ANOVA, P > 0.05) between MT/hCG-treated and control fish were observed in plasma testosterone (T) or 11-keto T (11-KT). Pituitary luteinizing hormone (LH) content was significantly lower in both the MT/hCG and hCG groups, compared to controls (2-way ANOVA, P < 0.001), while plasma LH was below detection limits in all treatments. At the onset of the experiment all but one fish were already differentiated into females, having ovaries with primary oocytes. No signs of vitellogenesis or sex inversion were observed in fish from the control and hCG groups during the study. On the contrary, the MT implants induced complete sex change after 12 weeks, with the gonads organized in lobules and cysts filled with germ cells at all stages of spermatogenesis, including spermatozoa. This sex inversion was permanent and fish underwent complete spermatogenesis again during the following year. The results demonstrate that the produced MT-implants, but not the hCG injections, were highly efficient in inducing both sex inversion and complete spermatogenesis in pre-pubertal dusky grouper at the completion of their second year in life. Production of male fish at such an early age may dramatically reduce by many years the time required for natural puberty, sex inversion and the production of sperm by dusky grouper reared under culture conditions. © 2006 Elsevier B.V. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Long-term treatments (April-June 2004) with 17α-methyltestosterone (MT) and/or human chorionic gonadotropin (hCG) were used to induce precocious sex change in 1-year-old juveniles (mean ± SD body weight of 131 ± 25 g) of the protogynous dusky grouper (Epinephelus marginatus). The MT treatment was given once a month using controlled-release implants (1.5 mg per implant, ∼11 mg kg- 1 body weight), whereas hCG was injected intramuscularly once a month (MT/hCG group) or every 2 weeks (hCG group). In vitro mean (± SEM) daily and total MT release from the implants was 22.6 ± 5.4 μg day- 1 implant- 1 and 686 ± 113 μg implant- 1, respectively. In vivo, plasma MT levels of European sea bas (Dicentrarchus labrax) used as model fish (203 ± 41 g body weight) and given a single MT implant were 18.5 ± 0.5 ng ml- 1 one day after implantation, declined to 9.6 ± 2.7 ng ml- 1 by day 11 and remained stable between 7.9 and 5.5 ng ml- 1 until day 32. Plasma MT levels were significantly elevated (2-way ANOVA, P < 0.01) in dusky grouper juveniles in response to the MT treatment, both 6 and 12 weeks after beginning the treatment. On the contrary, no significant differences (2-way ANOVA, P > 0.05) between MT/hCG-treated and control fish were observed in plasma testosterone (T) or 11-keto T (11-KT). Pituitary luteinizing hormone (LH) content was significantly lower in both the MT/hCG and hCG groups, compared to controls (2-way ANOVA, P < 0.001), while plasma LH was below detection limits in all treatments. At the onset of the experiment all but one fish were already differentiated into females, having ovaries with primary oocytes. No signs of vitellogenesis or sex inversion were observed in fish from the control and hCG groups during the study. On the contrary, the MT implants induced complete sex change after 12 weeks, with the gonads organized in lobules and cysts filled with germ cells at all stages of spermatogenesis, including spermatozoa. This sex inversion was permanent and fish underwent complete spermatogenesis again during the following year. The results demonstrate that the produced MT-implants, but not the hCG injections, were highly efficient in inducing both sex inversion and complete spermatogenesis in pre-pubertal dusky grouper at the completion of their second year in life. Production of male fish at such an early age may dramatically reduce by many years the time required for natural puberty, sex inversion and the production of sperm by dusky grouper reared under culture conditions. © 2006 Elsevier B.V. All rights reserved. |
2005 |
Papadaki, M; Piferrer, F; Zanuy, S; Maingot, E; Divanach, P; Mylonas, C C Journal of Fish Biology, 66 (4), pp. 938–956, 2005, ISSN: 00221112, (Publisher: Blackwell Publishing Ltd). @article{papadaki_growth_2005, title = {Growth, sex differentiation and gonad and plasma levels of sex steroids in male- and female-dominant populations of Dicentrarchus labrax obtained through repeated size grading}, author = {M Papadaki and F Piferrer and S Zanuy and E Maingot and P Divanach and C C Mylonas}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-17244363508&doi=10.1111%2fj.0022-1112.2005.00639.x&partnerID=40&md5=818526ad19bf4809e7b643ad51c39425}, doi = {10.1111/j.0022-1112.2005.00639.x}, issn = {00221112}, year = {2005}, date = {2005-01-01}, journal = {Journal of Fish Biology}, volume = {66}, number = {4}, pages = {938--956}, abstract = {Starting from 66 days post hatching (dph), European sea bass Dicentrarchus labrax were graded successively to create a fast growing (L-extreme) and a slow growing (S-extreme) population. The L-extreme population grew significantly larger (ANOVA}, note = {Publisher: Blackwell Publishing Ltd}, keywords = {}, pubstate = {published}, tppubtype = {article} } Starting from 66 days post hatching (dph), European sea bass Dicentrarchus labrax were graded successively to create a fast growing (L-extreme) and a slow growing (S-extreme) population. The L-extreme population grew significantly larger (ANOVA |
2004 |
Mylonas, C C; Papadaki, M; Pavlidis, M; Divanach, P Evaluation of egg production and quality in the Mediterranean red porgy (Pagrus pagrus) during two consecutive spawning seasons Journal Article Aquaculture, 232 (1-4), pp. 637–649, 2004, ISSN: 00448486. @article{mylonas_evaluation_2004, title = {Evaluation of egg production and quality in the Mediterranean red porgy (Pagrus pagrus) during two consecutive spawning seasons}, author = {C C Mylonas and M Papadaki and M Pavlidis and P Divanach}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-1542321216&doi=10.1016%2fS0044-8486%2803%2900534-9&partnerID=40&md5=bb798427551c7d2bdbf2d0812cf57e45}, doi = {10.1016/S0044-8486(03)00534-9}, issn = {00448486}, year = {2004}, date = {2004-01-01}, journal = {Aquaculture}, volume = {232}, number = {1-4}, pages = {637--649}, abstract = {Egg production from two broodstocks of captive-reared red porgy (Pagrus pagrus) was monitored for two consecutive seasons (2001 and 2002). Spawning lasted from January to April-May under water temperature between 15.8 and 19.2°C. Spawning was mostly daily, though over the course of the two spawning seasons, the mean interval was 1.5-1.2 days spawn-1. There was a large variation in daily fecundity without a consistent trend, except for a slight peak in the middle of the spawning season. Mean (S.E.M.) annual relative fecundity ranged between 408,300 (95,800) and 442,500 (180,800) eggs kg-1 year-1. Mean fertilization success increased significantly from 36.9 (2.0)% in 2001 to 68.9 (2.5)% in 2002, resulting in mean annual viable egg production of 174,800 (87,600) and 301,500 (99,800) eggs kg-1, respectively. There were no significant differences between the 2 years in other egg quality parameters, which ranged between 74.5 and 79. 3% 1-day embryo survival, 81.6-85.5% hatching success and 76.7-78.8% 5-day larval survival. Of the relations examined, fertilization % had a significantly positive correlation with 1-day embryo survival, which in turn was significantly correlated with hatching %. Larval survival was further correlated with hatching %. These data suggest that decisions on whether to proceed with the incubation of a batch of eggs and rearing of the larvae can be made within 1 day from egg collection, before much effort is invested by the hatchery. The present study presents further information on the spawning kinetics, and egg production and quality characteristics of the Mediterranean red porgy in culture, and demonstrates the suitability of this species for reproduction in captivity. © 2004 Elsevier B.V. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Egg production from two broodstocks of captive-reared red porgy (Pagrus pagrus) was monitored for two consecutive seasons (2001 and 2002). Spawning lasted from January to April-May under water temperature between 15.8 and 19.2°C. Spawning was mostly daily, though over the course of the two spawning seasons, the mean interval was 1.5-1.2 days spawn-1. There was a large variation in daily fecundity without a consistent trend, except for a slight peak in the middle of the spawning season. Mean (S.E.M.) annual relative fecundity ranged between 408,300 (95,800) and 442,500 (180,800) eggs kg-1 year-1. Mean fertilization success increased significantly from 36.9 (2.0)% in 2001 to 68.9 (2.5)% in 2002, resulting in mean annual viable egg production of 174,800 (87,600) and 301,500 (99,800) eggs kg-1, respectively. There were no significant differences between the 2 years in other egg quality parameters, which ranged between 74.5 and 79. 3% 1-day embryo survival, 81.6-85.5% hatching success and 76.7-78.8% 5-day larval survival. Of the relations examined, fertilization % had a significantly positive correlation with 1-day embryo survival, which in turn was significantly correlated with hatching %. Larval survival was further correlated with hatching %. These data suggest that decisions on whether to proceed with the incubation of a batch of eggs and rearing of the larvae can be made within 1 day from egg collection, before much effort is invested by the hatchery. The present study presents further information on the spawning kinetics, and egg production and quality characteristics of the Mediterranean red porgy in culture, and demonstrates the suitability of this species for reproduction in captivity. © 2004 Elsevier B.V. All rights reserved. |
Mylonas, C C; Papandroulakis, N; Smboukis, A; Papadaki, M; Divanach, P Induction of spawning of cultured greater amberjack (Seriola dumerili) using GnRHa implants Journal Article Aquaculture, 237 (1-4), pp. 141–154, 2004, ISSN: 00448486. @article{mylonas_induction_2004, title = {Induction of spawning of cultured greater amberjack (Seriola dumerili) using GnRHa implants}, author = {C C Mylonas and N Papandroulakis and A Smboukis and M Papadaki and P Divanach}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-3142566876&doi=10.1016%2fj.aquaculture.2004.04.015&partnerID=40&md5=1d5f2c1607615bf23df2ad0e72aaa783}, doi = {10.1016/j.aquaculture.2004.04.015}, issn = {00448486}, year = {2004}, date = {2004-01-01}, journal = {Aquaculture}, volume = {237}, number = {1-4}, pages = {141--154}, abstract = {The objective of the current study was to examine the possibility of maturing Mediterranean greater amberjack (Seriola dumerili) in culture at two different facilities in Greece and inducing spawning using gonadotropin releasing-hormone agonist (GnRHa) implants. Males in both stocks (n=8) were in spermiating condition in mid June, though sperm motility was low ranging between 5% and 30%, while motility duration ranged between 2.1 and 2.5 min. Females of the first stock (n=4) at the same time had ovaries with either primary oocytes or early vitellogenic oocytes at advanced stages of atresia, indicating a failure in oogenesis. On the contrary, the only female of the second stock contained oocytes at all stages of oogenesis, including early final oocyte maturation (FOM; oocyte diameter 650 μm). Implantation with a GnRHa implant induced the first spawn about 36 h later. In the absence of another spawn, a gonadal biopsy was taken 15 days later, indicating the existence of more oocytes at post vitellogenesis and some with almost complete lipid droplet coalescence. A second GnRHa implantation at this time resulted in consecutive egg releases after 36 h, 4 and 5 days, with fertilized eggs only at 36 h and 5 days. The study underlines the existence of important reproductive dysfunctions of greater amberjack in captivity, and demonstrates that GnRHa implants can be used for the induction of multiple spawns of viable eggs. © 2004 Elsevier B.V. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The objective of the current study was to examine the possibility of maturing Mediterranean greater amberjack (Seriola dumerili) in culture at two different facilities in Greece and inducing spawning using gonadotropin releasing-hormone agonist (GnRHa) implants. Males in both stocks (n=8) were in spermiating condition in mid June, though sperm motility was low ranging between 5% and 30%, while motility duration ranged between 2.1 and 2.5 min. Females of the first stock (n=4) at the same time had ovaries with either primary oocytes or early vitellogenic oocytes at advanced stages of atresia, indicating a failure in oogenesis. On the contrary, the only female of the second stock contained oocytes at all stages of oogenesis, including early final oocyte maturation (FOM; oocyte diameter 650 μm). Implantation with a GnRHa implant induced the first spawn about 36 h later. In the absence of another spawn, a gonadal biopsy was taken 15 days later, indicating the existence of more oocytes at post vitellogenesis and some with almost complete lipid droplet coalescence. A second GnRHa implantation at this time resulted in consecutive egg releases after 36 h, 4 and 5 days, with fertilized eggs only at 36 h and 5 days. The study underlines the existence of important reproductive dysfunctions of greater amberjack in captivity, and demonstrates that GnRHa implants can be used for the induction of multiple spawns of viable eggs. © 2004 Elsevier B.V. All rights reserved. |
2003 |
Mylonas, C C; Papadaki, M; Divanach, P Seasonal changes in sperm production and quality in the red porgy Pagrus pagrus (L.) Journal Article Aquaculture Research, 34 (13), pp. 1161–1170, 2003, ISSN: 1355557X. @article{mylonas_seasonal_2003, title = {Seasonal changes in sperm production and quality in the red porgy Pagrus pagrus (L.)}, author = {C C Mylonas and M Papadaki and P Divanach}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0242286610&doi=10.1046%2fj.1365-2109.2003.00922.x&partnerID=40&md5=035f37a6d19b84e81a7004fb96f03fec}, doi = {10.1046/j.1365-2109.2003.00922.x}, issn = {1355557X}, year = {2003}, date = {2003-01-01}, journal = {Aquaculture Research}, volume = {34}, number = {13}, pages = {1161--1170}, abstract = {Cultured red porgy Pagrus pagrus (L.) males (n = 6) were sampled every 2 weeks for milt, in order to monitor changes in sperm quality parameters during a whole spawning period. On 11 January 2001, 60% of the fish were spermiating, increasing to 100% in mid-February and dropping to 30% by mid-April. Sperm density showed a slight increasing trend, with mean values ranging between 8.6 and 23.7 × 109 spermatozoa mL-1. Sperm motility percentage exhibited a significant improvement during the spawning season (analysis of variance (ANOVA) P = 0.0001). The duration of forward motility for the major part of the monitoring period ranged between 2 and 4 min. Red porgy spermatozoa maintained their viability for many days after whole storage of milt at 4°C. During the monitoring period there were significant changes in the mean duration of sperm survival after cold storage, ranging from 5 to 12 days. The total volume of expressible milt was maximal on 28 March, increasing from a mean value of 1.7 mL to 5.3 mL kg-1. Milt production of captive-reared red porgy does not appear to be limiting, when compared with the volume of expressible milt produced by other cultured marine fishes.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Cultured red porgy Pagrus pagrus (L.) males (n = 6) were sampled every 2 weeks for milt, in order to monitor changes in sperm quality parameters during a whole spawning period. On 11 January 2001, 60% of the fish were spermiating, increasing to 100% in mid-February and dropping to 30% by mid-April. Sperm density showed a slight increasing trend, with mean values ranging between 8.6 and 23.7 × 109 spermatozoa mL-1. Sperm motility percentage exhibited a significant improvement during the spawning season (analysis of variance (ANOVA) P = 0.0001). The duration of forward motility for the major part of the monitoring period ranged between 2 and 4 min. Red porgy spermatozoa maintained their viability for many days after whole storage of milt at 4°C. During the monitoring period there were significant changes in the mean duration of sperm survival after cold storage, ranging from 5 to 12 days. The total volume of expressible milt was maximal on 28 March, increasing from a mean value of 1.7 mL to 5.3 mL kg-1. Milt production of captive-reared red porgy does not appear to be limiting, when compared with the volume of expressible milt produced by other cultured marine fishes. |