2024 |
Loufi, Katerina; Papadakis, Ioannis E; Makridis, Pavlos Aquaculture Nutrition, 2024 , pp. 1–15, 2024, ISSN: 1365-2095, 1353-5773. @article{loufi_use_2024, title = {The Use of Acartia tonsa Nauplii during the First Days of Feeding on the Ontogeny of the Digestive System of Greater Amberjack (Seriola dumerili Risso, 1810)}, author = {Katerina Loufi and Ioannis E Papadakis and Pavlos Makridis}, editor = {Yanjiao Zhang}, url = {https://www.hindawi.com/journals/anu/2024/1826300/ https://imbbc.hcmr.gr/wp-content/uploads/2024/07/2024-Loufi-AquaNutri-33.pdf}, doi = {10.1155/2024/1826300}, issn = {1365-2095, 1353-5773}, year = {2024}, date = {2024-07-10}, urldate = {2024-07-10}, journal = {Aquaculture Nutrition}, volume = {2024}, pages = {1--15}, abstract = {The effect of feeding greater amberjack with copepod nauplii (Acartia tonsa) on the ontogeny of the digestive system was observed until 40 days after hatching (DAH). Copepods are part of the diet of fish larvae in nature, and they are rich in highly unsaturated fatty acids and free amino acids that enhance the digestive capacity of the fish. In a marine hatchery, four cylindroconical tanks of 2,700 L were stocked with about 150 × 103 greater amberjack larvae (Seriola dumerili) in each. The larvae were initially fed from 3 to 17 DAH in two tanks with copepod nauplii and rotifers (Brachionus sp.; Copepods group), while in the other two tanks, they were fed only with rotifers (Control group) during the same period. All the tanks were fed with rotifers (3–27 DAH), Artemia nauplii (12–22 DAH), enriched Artemia metanauplii (20–30 DAH), and formulated diet (25–40 DAH). Fish samples were taken regularly (every 2 or 4 days) for histological analysis and every day for the measurement of total length (TL). The TL was 3.7, 4.5 ± 0.1, 6.1, 11, 17.3 ± 0.1 and 20.3 ± 2.3 mm at 4, 10, 16, 22, 30, and 40 DAH, respectively. Copepod-fed fish showed higher TL in the last 2 days of the trial ( p textless 0.05 ), while mortality rates were lower in the beginning of the trial 10–17 DAH, ( p textless 0.05 ). In addition, copepods-fed fish had less skeletal deformities ( p textless 0.05 ). Pyloric caeca appeared earlier in the Copepods group compared with the Control, while the length and surface of the villi, the abundance of goblet cells/100 μm of intestine length, and the area covered with lipid vacuoles in the liver were significantly higher in the Copepods group ( p textless 0.05 ). We can conclude that the use of copepods in the diet of the greater amberjack larvae can improve the ontogeny of the digestive system.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The effect of feeding greater amberjack with copepod nauplii (Acartia tonsa) on the ontogeny of the digestive system was observed until 40 days after hatching (DAH). Copepods are part of the diet of fish larvae in nature, and they are rich in highly unsaturated fatty acids and free amino acids that enhance the digestive capacity of the fish. In a marine hatchery, four cylindroconical tanks of 2,700 L were stocked with about 150 × 103 greater amberjack larvae (Seriola dumerili) in each. The larvae were initially fed from 3 to 17 DAH in two tanks with copepod nauplii and rotifers (Brachionus sp.; Copepods group), while in the other two tanks, they were fed only with rotifers (Control group) during the same period. All the tanks were fed with rotifers (3–27 DAH), Artemia nauplii (12–22 DAH), enriched Artemia metanauplii (20–30 DAH), and formulated diet (25–40 DAH). Fish samples were taken regularly (every 2 or 4 days) for histological analysis and every day for the measurement of total length (TL). The TL was 3.7, 4.5 ± 0.1, 6.1, 11, 17.3 ± 0.1 and 20.3 ± 2.3 mm at 4, 10, 16, 22, 30, and 40 DAH, respectively. Copepod-fed fish showed higher TL in the last 2 days of the trial ( p textless 0.05 ), while mortality rates were lower in the beginning of the trial 10–17 DAH, ( p textless 0.05 ). In addition, copepods-fed fish had less skeletal deformities ( p textless 0.05 ). Pyloric caeca appeared earlier in the Copepods group compared with the Control, while the length and surface of the villi, the abundance of goblet cells/100 μm of intestine length, and the area covered with lipid vacuoles in the liver were significantly higher in the Copepods group ( p textless 0.05 ). We can conclude that the use of copepods in the diet of the greater amberjack larvae can improve the ontogeny of the digestive system. |
2023 |
Samaras, Athanasios; Tsoukali, Panagiota; Katsika, Lydia; Pavlidis, Michail; Papadakis, Ioannis E Aquaculture, 562 , pp. 738830, 2023, ISSN: 00448486. @article{samaras_chronic_2023, title = {Chronic impact of exposure to low dissolved oxygen on the physiology of Dicentrarchus labrax and Sparus aurata and its effects on the acute stress response}, author = {Athanasios Samaras and Panagiota Tsoukali and Lydia Katsika and Michail Pavlidis and Ioannis E Papadakis}, url = {https://imbbc.hcmr.gr/wp-content/uploads/2022/10/2022-Samaras-AQUA-66-preprint-1.pdf https://linkinghub.elsevier.com/retrieve/pii/S0044848622009474}, doi = {10.1016/j.aquaculture.2022.738830}, issn = {00448486}, year = {2023}, date = {2023-01-01}, urldate = {2022-10-12}, journal = {Aquaculture}, volume = {562}, pages = {738830}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
2022 |
de Mello, Paulo H; Divanach, Pascal; Papadakis, Ioannis E Aquaculture Research, 53 (9), pp. 3416–3429, 2022, ISSN: 1355-557X, 1365-2109. @article{de_mello_temperature_2022, title = {Temperature influences growth, digestive system ontogeny and lipids deposition in the liver in gilthead seabream ( textitSparus aurata ) larvae and juveniles}, author = {Paulo H de Mello and Pascal Divanach and Ioannis E Papadakis}, url = {https://imbbc.hcmr.gr/wp-content/uploads/2022/07/2022-de-Mello-ARE-pre-print-44.pdf https://onlinelibrary.wiley.com/doi/10.1111/are.15849}, doi = {10.1111/are.15849}, issn = {1355-557X, 1365-2109}, year = {2022}, date = {2022-06-01}, urldate = {2022-07-29}, journal = {Aquaculture Research}, volume = {53}, number = {9}, pages = {3416--3429}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
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 |
Samaras, Athanasios; Dimitroglou, Arkadios; Kollias, Spyridon; Skouradakis, Grigorios; Papadakis, Ioannis E; Pavlidis, Michail Cortisol concentration in scales is a valid indicator for the assessment of chronic stress in European sea bass, Dicentrarchus labrax L Journal Article Aquaculture, 545 , pp. 737257, 2021, ISSN: 00448486, (MULTI). @article{samaras_cortisol_2021, title = {Cortisol concentration in scales is a valid indicator for the assessment of chronic stress in European sea bass, Dicentrarchus labrax L}, author = {Athanasios Samaras and Arkadios Dimitroglou and Spyridon Kollias and Grigorios Skouradakis and Ioannis E Papadakis and Michail Pavlidis}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0044848621009200}, doi = {10.1016/j.aquaculture.2021.737257}, issn = {00448486}, year = {2021}, date = {2021-01-01}, urldate = {2022-01-17}, journal = {Aquaculture}, volume = {545}, pages = {737257}, note = {MULTI}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
2020 |
Pérez, José A; Papadakis, Ioannis E; Papandroulakis, Nikos; Cruces, Lorenzo; Cotou, Efthimia; Gisbert, Enric; Lorenzo, Antonio; Mylonas, Constantinos C; Rodríguez, Covadonga Aquaculture Nutrition, pp. anu.13128, 2020, ISSN: 1353-5773, 1365-2095. @article{perez_ontogeny_2020, title = {The ontogeny of greater amberjack digestive and antioxidant defence systems under different rearing conditions: A histological and enzymatic approach}, author = {José A Pérez and Ioannis E Papadakis and Nikos Papandroulakis and Lorenzo Cruces and Efthimia Cotou and Enric Gisbert and Antonio Lorenzo and Constantinos C Mylonas and Covadonga Rodríguez}, url = {https://onlinelibrary.wiley.com/doi/10.1111/anu.13128}, doi = {10.1111/anu.13128}, issn = {1353-5773, 1365-2095}, year = {2020}, date = {2020-09-01}, urldate = {2020-10-05}, journal = {Aquaculture Nutrition}, pages = {anu.13128}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Loi, Barbara; Papadakis, Ioannis E; Leggieri, Francesca; Papiol, Gemma [Giménez; Vallainc, Dario Aquaculture, 526 , pp. 735386, 2020, ISSN: 0044-8486. @article{loi_ontogeny_2020, title = {Ontogeny of the digestive system and eye of reared flathead grey mullet, Mugil cephalus (Linnaeus, 1758), and evaluation of lipid deposition in the liver according to the feeding protocol}, author = {Barbara Loi and Ioannis E Papadakis and Francesca Leggieri and Gemma [Giménez Papiol and Dario Vallainc}, url = {http://www.sciencedirect.com/science/article/pii/S0044848620302519}, doi = {https://doi.org/10.1016/j.aquaculture.2020.735386}, issn = {0044-8486}, year = {2020}, date = {2020-01-01}, journal = {Aquaculture}, volume = {526}, pages = {735386}, abstract = {Ontogenic development of the digestive system and eye was studied in flathead grey mullet (Mugil cephalus) from hatching to the juvenile stage (69 days after hatching, dah), in rearing conditions. Moreover, the liver lipid content (area covered with lipid vacuoles, ACLV%) was evaluated according to the feeding protocol in association with the stomach content, using histological methods. Larval growth rate was slow until tail flexion was achieved ( 14–15 dah), subsequently the growth was very rapid until reaching the mean total length ± SD of 22.27 ± 2.79 mm at the end of the rearing. The main structures of the digestive system were completely developed by 17 dah (395 degree days). Photopic vision began by 3 dah with the appearance of cones, while the ability for scotopic vision was acquired at 17 dah, when the larvae started gained the ability to see and catch prey in reduced light conditions. When the feeding protocol included both rotifers and Artemia nauplii, the mean ACLV remained high (15.66 ± 3.90%), as did the occurrence of lipid vacuoles in the intestine. ACLV in the liver started to decrease significantly during the weaning phase (until 40 dah, when it was 3.80 ± 2.51%). This was probably linked to the decreased total energy received by the larvae, because of the gradual reduction of the delivered Artemia coupled with the low acceptance of the artificial food. However, larvae accepted early artificial feed which was found in the stomach content a few days after the first administration. Consumption of growing amounts of artificial feed resulted in a growing ACLV, which rose again up to 20.38 ± 6.05% at 62 dah. The transition to a different artificial food (with half the lipid dose compared to the first one) led to a non-significant drop in ACLV in the liver, decreasing as much as 13.66 ± 7.19% on the last day of the rearing period. These results provide important information for the biology of this promising species for aquaculture, indicating that flathead grey mullet larvae rapidly develop the basic structures of the digestive and visual systems required to successfully overcome the most critical stage of commercial rearing. The study also confirms that histological evaluation of liver lipid content using the ACLV is a valuable tool in commercial aquaculture in order to identify the weaknesses of a feeding protocol and improve larval rearing protocols, and therefore production efficiency.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Ontogenic development of the digestive system and eye was studied in flathead grey mullet (Mugil cephalus) from hatching to the juvenile stage (69 days after hatching, dah), in rearing conditions. Moreover, the liver lipid content (area covered with lipid vacuoles, ACLV%) was evaluated according to the feeding protocol in association with the stomach content, using histological methods. Larval growth rate was slow until tail flexion was achieved ( 14–15 dah), subsequently the growth was very rapid until reaching the mean total length ± SD of 22.27 ± 2.79 mm at the end of the rearing. The main structures of the digestive system were completely developed by 17 dah (395 degree days). Photopic vision began by 3 dah with the appearance of cones, while the ability for scotopic vision was acquired at 17 dah, when the larvae started gained the ability to see and catch prey in reduced light conditions. When the feeding protocol included both rotifers and Artemia nauplii, the mean ACLV remained high (15.66 ± 3.90%), as did the occurrence of lipid vacuoles in the intestine. ACLV in the liver started to decrease significantly during the weaning phase (until 40 dah, when it was 3.80 ± 2.51%). This was probably linked to the decreased total energy received by the larvae, because of the gradual reduction of the delivered Artemia coupled with the low acceptance of the artificial food. However, larvae accepted early artificial feed which was found in the stomach content a few days after the first administration. Consumption of growing amounts of artificial feed resulted in a growing ACLV, which rose again up to 20.38 ± 6.05% at 62 dah. The transition to a different artificial food (with half the lipid dose compared to the first one) led to a non-significant drop in ACLV in the liver, decreasing as much as 13.66 ± 7.19% on the last day of the rearing period. These results provide important information for the biology of this promising species for aquaculture, indicating that flathead grey mullet larvae rapidly develop the basic structures of the digestive and visual systems required to successfully overcome the most critical stage of commercial rearing. The study also confirms that histological evaluation of liver lipid content using the ACLV is a valuable tool in commercial aquaculture in order to identify the weaknesses of a feeding protocol and improve larval rearing protocols, and therefore production efficiency. |
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} } |
2018 |
Papadakis, I E; Kentouri, M; Divanach, P; Mylonas, C C Ontogeny of the eye of meagre (Argyrosomus regius) from hatching to juvenile and implications to commercial larval rearing Journal Article Aquaculture, 484 , pp. 32–43, 2018, ISSN: 00448486, (Publisher: Elsevier B.V.). @article{papadakis_ontogeny_2018, title = {Ontogeny of the eye of meagre (Argyrosomus regius) from hatching to juvenile and implications to commercial larval rearing}, author = {I E Papadakis and M Kentouri and P Divanach and C C Mylonas}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85032915502&doi=10.1016%2fj.aquaculture.2017.10.038&partnerID=40&md5=6d5582db60caf9774e0ef281ba47a57f}, doi = {10.1016/j.aquaculture.2017.10.038}, issn = {00448486}, year = {2018}, date = {2018-01-01}, journal = {Aquaculture}, volume = {484}, pages = {32--43}, abstract = {The histological development of the visual system of meagre (Argyrosomus regius) was studied from hatching to juvenile stage (44 days post hatching, dph), under aquaculture rearing conditions. The cones, horizontal, bipolar, amacrine and ganglia cells appeared already at 3 dph at a total body length (TL) of 3.11 ± 0.21 mm, at the stage of mouth opening. Rods appeared at 6 dph (TL 4.16 ± 0.73 mm) and increased their density continually during the monitoring period. On the contrary at the same period, the evolution of the number of cones, horizontal, bipolar, amacrine and ganglia cells in the retina were reduced. While photopic sensitivity increased over time, meagre may be considered as a species with well-developed scotopic sensitivity as well, already by 17 dph (TL 8.14 ± 1.64 mm). This observation suggests that instead of the commonly used 24-h continuous high light intensities used in larval rearing protocols of meagre, lower light intensities should be employed, especially during the night hours. Histological visual acuity increased with larval development and appeared to stabilize by the early juvenile stage. Based on the estimated histological visual acuity and the theoretical distance at which rotifers and Artemia may be identified by meagre larvae, minimum prey densities should be 0.5 rotifers and 0.009 Artemia ml− 1 during their first use as feed items. The study demonstrated that the majority of ontogenetic events that are related with retinal differentiation and the function of the eye occurred very early during larval development in meagre. The results provide important information for the biology of the species, as well as for the optimization of larval rearing conditions regarding light management and prey item density under aquaculture conditions. © 2017 Elsevier B.V.}, note = {Publisher: Elsevier B.V.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The histological development of the visual system of meagre (Argyrosomus regius) was studied from hatching to juvenile stage (44 days post hatching, dph), under aquaculture rearing conditions. The cones, horizontal, bipolar, amacrine and ganglia cells appeared already at 3 dph at a total body length (TL) of 3.11 ± 0.21 mm, at the stage of mouth opening. Rods appeared at 6 dph (TL 4.16 ± 0.73 mm) and increased their density continually during the monitoring period. On the contrary at the same period, the evolution of the number of cones, horizontal, bipolar, amacrine and ganglia cells in the retina were reduced. While photopic sensitivity increased over time, meagre may be considered as a species with well-developed scotopic sensitivity as well, already by 17 dph (TL 8.14 ± 1.64 mm). This observation suggests that instead of the commonly used 24-h continuous high light intensities used in larval rearing protocols of meagre, lower light intensities should be employed, especially during the night hours. Histological visual acuity increased with larval development and appeared to stabilize by the early juvenile stage. Based on the estimated histological visual acuity and the theoretical distance at which rotifers and Artemia may be identified by meagre larvae, minimum prey densities should be 0.5 rotifers and 0.009 Artemia ml− 1 during their first use as feed items. The study demonstrated that the majority of ontogenetic events that are related with retinal differentiation and the function of the eye occurred very early during larval development in meagre. The results provide important information for the biology of the species, as well as for the optimization of larval rearing conditions regarding light management and prey item density under aquaculture conditions. © 2017 Elsevier B.V. |
2014 |
Loizides, M; Georgakopoulou, E; Christou, M; Iliopoulou, M; Papadakis, I; Katharios, P; Divanach, P; Koumoundouros, G Thermally-induced phenotypic plasticity in gilthead seabream Sparus aurata L. (Perciformes, Sparidae) Journal Article Aquaculture, 432 , pp. 383–388, 2014, ISSN: 00448486, (Publisher: Elsevier). @article{loizides_thermally-induced_2014, title = {Thermally-induced phenotypic plasticity in gilthead seabream Sparus aurata L. (Perciformes, Sparidae)}, author = {M Loizides and E Georgakopoulou and M Christou and M Iliopoulou and I Papadakis and P Katharios and P Divanach and G Koumoundouros}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84907594566&doi=10.1016%2fj.aquaculture.2014.06.002&partnerID=40&md5=2d0fb32cff829342c38f272f14f01d7d}, doi = {10.1016/j.aquaculture.2014.06.002}, issn = {00448486}, year = {2014}, date = {2014-01-01}, journal = {Aquaculture}, volume = {432}, pages = {383--388}, abstract = {Finfish present a great ability to modify their phenotype in response to environmental conditions especially in the early ontogenetic period. Such plastic phenotypic responses have a great importance, from both the ecological and aquaculture point of view. The present study examined the effect of water temperature on the ontogeny and juvenile phenotype of Sparus aurata L. Six combinations of three temperatures (16, 19, and 22. °C) were applied during different phases of ontogeny up to the juvenile stage (ca 33-37. mm standard length, SL). Elevated temperature resulted in a relative acceleration of differentiation versus growth, which morphologically was evident as a significantly smaller SL (ca 11% decrease) at different ontogenetic events (development of fins, squamation and body shape). Moreover, geometric morphometric analysis clearly showed a significant effect of water temperature during early ontogeny on the juvenile body-shape. Thermally-induced variation of juvenile body shape was mainly expressed across the first canonical axis (56.4% explained variance), which discriminated the groups of highest temperatures from the rest. Water temperature mainly affected the position of the bases of supraoccipital and of basioccipital bones, of the upper jaw, as well as of the dorsal, anal and pelvic fins. The results are discussed with respect to the potential use of thermal manipulations during the hatchery phase to control the phenotype of S. aurata at the end of on-growing phase, i.e. at commercial size. © 2014 Elsevier B.V.}, note = {Publisher: Elsevier}, keywords = {}, pubstate = {published}, tppubtype = {article} } Finfish present a great ability to modify their phenotype in response to environmental conditions especially in the early ontogenetic period. Such plastic phenotypic responses have a great importance, from both the ecological and aquaculture point of view. The present study examined the effect of water temperature on the ontogeny and juvenile phenotype of Sparus aurata L. Six combinations of three temperatures (16, 19, and 22. °C) were applied during different phases of ontogeny up to the juvenile stage (ca 33-37. mm standard length, SL). Elevated temperature resulted in a relative acceleration of differentiation versus growth, which morphologically was evident as a significantly smaller SL (ca 11% decrease) at different ontogenetic events (development of fins, squamation and body shape). Moreover, geometric morphometric analysis clearly showed a significant effect of water temperature during early ontogeny on the juvenile body-shape. Thermally-induced variation of juvenile body shape was mainly expressed across the first canonical axis (56.4% explained variance), which discriminated the groups of highest temperatures from the rest. Water temperature mainly affected the position of the bases of supraoccipital and of basioccipital bones, of the upper jaw, as well as of the dorsal, anal and pelvic fins. The results are discussed with respect to the potential use of thermal manipulations during the hatchery phase to control the phenotype of S. aurata at the end of on-growing phase, i.e. at commercial size. © 2014 Elsevier B.V. |
Glaropoulos, A; Papadakis, V M; Papadakis, I E; Georgara, A; Kentouri, M Sea bream interactions toward the aquaculture net due to the presence of micro-fouling Journal Article Aquaculture International, 22 (3), pp. 1203–1214, 2014, ISSN: 09676120, (Publisher: Kluwer Academic Publishers). @article{glaropoulos_sea_2014, title = {Sea bream interactions toward the aquaculture net due to the presence of micro-fouling}, author = {A Glaropoulos and V M Papadakis and I E Papadakis and A Georgara and M Kentouri}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84899996933&doi=10.1007%2fs10499-013-9741-7&partnerID=40&md5=ef0e62c48fca1d896f2a6fe4b5fcb05a}, doi = {10.1007/s10499-013-9741-7}, issn = {09676120}, year = {2014}, date = {2014-01-01}, journal = {Aquaculture International}, volume = {22}, number = {3}, pages = {1203--1214}, abstract = {The technology of floating sea cages that is largely used in the Mediterranean aquaculture provides optimal conditions for the development of marine fouling. The present study investigates the influence of micro-fouling developed on a net, on sea bream behavior. Negative effects of biofouling were not tested since the study was performed under laboratory conditions and for short experimental period. The net condition (micro-fouling filaments) is further examined in comparison with a similar green-brown colored and a white net pen. From the results obtained, it can be concluded that micro-fouling filaments highly induce net biting. In contrast, the colored net tested in this study negatively affected sea bream interactions on the net. Results lead to the conclusion that the fouling filaments are more important to sea bream attraction than the net color, while both variables affect species behavior. © 2013 Springer Science+Business Media Dordrecht.}, note = {Publisher: Kluwer Academic Publishers}, keywords = {}, pubstate = {published}, tppubtype = {article} } The technology of floating sea cages that is largely used in the Mediterranean aquaculture provides optimal conditions for the development of marine fouling. The present study investigates the influence of micro-fouling developed on a net, on sea bream behavior. Negative effects of biofouling were not tested since the study was performed under laboratory conditions and for short experimental period. The net condition (micro-fouling filaments) is further examined in comparison with a similar green-brown colored and a white net pen. From the results obtained, it can be concluded that micro-fouling filaments highly induce net biting. In contrast, the colored net tested in this study negatively affected sea bream interactions on the net. Results lead to the conclusion that the fouling filaments are more important to sea bream attraction than the net color, while both variables affect species behavior. © 2013 Springer Science+Business Media Dordrecht. |
2013 |
Papadakis, I E; Papadakis, V M; Glaropoulos, A; Petroutsos, S I; Gonzalez, Png L; Kentouri, M Do the visual conditions at the point of escape affect European sea bass escape behavior? Journal Article Mediterranean Marine Science, 14 (1), pp. 172, 2013, ISSN: 1791-6763, 1108-393X. @article{papadakis_visual_2013, title = {Do the visual conditions at the point of escape affect European sea bass escape behavior?}, author = {I E Papadakis and V M Papadakis and A Glaropoulos and S I Petroutsos and Png L Gonzalez and M Kentouri}, url = {https://ejournals.epublishing.ekt.gr/index.php/hcmr-med-mar-sc/article/view/12330}, doi = {10.12681/mms.360}, issn = {1791-6763, 1108-393X}, year = {2013}, date = {2013-03-01}, urldate = {2020-08-17}, journal = {Mediterranean Marine Science}, volume = {14}, number = {1}, pages = {172}, abstract = {European sea bass (Dicentrarchus labrax), an important species for the Mediterranean aquaculture industry, has been reported to escape from sea cage installations. Fish escapes are caused mainly by operational and technical failures that eventually result into a creation of a tear. Escapees may interact with wild stocks through interbreeding, transfer of pathogens and competition for food. The aim of this study was to examine at which extent the presence of a visible obstacle close to a tear on the net have an influence on sea bass propensity to escape. Fish were initially confined into small sea cages, with a tear at one side. The escape behavior was tested under experimental conditions. It is clearly demonstrated that sea bass was able to locate a tear on the net pen, immediately after its appearance. Crossings occurred in all cages, in singles or in a series of up to seven individuals. The presence of an obstacle close to the net tear altered the escape behavior of D. labrax resulting in a delay that eventually reduced the escape rate. Concluding, it is highly recommended that sea bass cages should be kept internally the culture array. Furthermore, the placement of artificial obstacles close to the sea cages could be an efficient practice that mitigates the escape risk after severe environmental conditions.}, keywords = {}, pubstate = {published}, tppubtype = {article} } European sea bass (Dicentrarchus labrax), an important species for the Mediterranean aquaculture industry, has been reported to escape from sea cage installations. Fish escapes are caused mainly by operational and technical failures that eventually result into a creation of a tear. Escapees may interact with wild stocks through interbreeding, transfer of pathogens and competition for food. The aim of this study was to examine at which extent the presence of a visible obstacle close to a tear on the net have an influence on sea bass propensity to escape. Fish were initially confined into small sea cages, with a tear at one side. The escape behavior was tested under experimental conditions. It is clearly demonstrated that sea bass was able to locate a tear on the net pen, immediately after its appearance. Crossings occurred in all cages, in singles or in a series of up to seven individuals. The presence of an obstacle close to the net tear altered the escape behavior of D. labrax resulting in a delay that eventually reduced the escape rate. Concluding, it is highly recommended that sea bass cages should be kept internally the culture array. Furthermore, the placement of artificial obstacles close to the sea cages could be an efficient practice that mitigates the escape risk after severe environmental conditions. |
Papadakis, I E; Kentouri, M; Divanach, P; Mylonas, C C Aquaculture, 388-391 (1), pp. 76–88, 2013, ISSN: 00448486, (Publisher: Elsevier B.V.). @article{papadakis_ontogeny_2013, title = {Ontogeny of the digestive system of meagre Argyrosomus regius reared in a mesocosm, and quantitative changes of lipids in the liver from hatching to juvenile}, author = {I E Papadakis and M Kentouri and P Divanach and C C Mylonas}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84873700252&doi=10.1016%2fj.aquaculture.2013.01.012&partnerID=40&md5=f4c62c1417bb80d113e957f7d9a763ac}, doi = {10.1016/j.aquaculture.2013.01.012}, issn = {00448486}, year = {2013}, date = {2013-01-01}, journal = {Aquaculture}, volume = {388-391}, number = {1}, pages = {76--88}, abstract = {Histological development of the digestive systemwas studied in association with feeding preferences in meagre (Argyrosomus regius) fromhatching to juvenile (44 days after hatching, dah), using amesocosmsystem. In addition, the liver lipid content was evaluated using histological methods (area covered with lipid vacuoles, ACLV%). The ontogeny of the digestive system was completed by 19 dah (or 444 degree days) with the gastric glands appearing at 15 dah (361 degree days), the pyloric ceaca at 17 dah (404 degree days) and the Y-shaped stomach formed at 19 dah (444 degree days). The rearing period was characterized first by relatively slow growth until tail flexion ( 15 dah) and fast growth thereafter (mean±SD total length of 45.14±4.00 mm at 44 dah). When the feeding protocol included exclusively rotifers, mean ACLV remained low (2.39±0.34%) while feeding on Artemia nauplii and copepods increased liver ACLV to 47.18±6.56% at 20 dah. Changes in the feeding protocol were reflected in feeding preferences (stomach content), and variations of liver lipid content and the occurrence of vacuoles in the intestine. During transition from live prey to artificial feed ( 28 dah), ACLV decreased significantly - indicating amalnutrition period - concomitantwith a delay in the acceptance of artificial feed of 8 days. Thereafter, consumption of artificial feed resulted in an increased ACLV to 56.3±7.6% at 36 dah. The results indicate that during early development meagre is a fast growing species, developing rapidly the structures and basic organs of the digestive system required to overcome successfully the critical stages of larval rearing. The study also shows that histological evaluation of liver lipid content using the ACLV may be a valuable tool incommercial aquaculture to improve larval rearing protocols, and production efficiency. © 2013 Elsevier B.V.}, note = {Publisher: Elsevier B.V.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Histological development of the digestive systemwas studied in association with feeding preferences in meagre (Argyrosomus regius) fromhatching to juvenile (44 days after hatching, dah), using amesocosmsystem. In addition, the liver lipid content was evaluated using histological methods (area covered with lipid vacuoles, ACLV%). The ontogeny of the digestive system was completed by 19 dah (or 444 degree days) with the gastric glands appearing at 15 dah (361 degree days), the pyloric ceaca at 17 dah (404 degree days) and the Y-shaped stomach formed at 19 dah (444 degree days). The rearing period was characterized first by relatively slow growth until tail flexion ( 15 dah) and fast growth thereafter (mean±SD total length of 45.14±4.00 mm at 44 dah). When the feeding protocol included exclusively rotifers, mean ACLV remained low (2.39±0.34%) while feeding on Artemia nauplii and copepods increased liver ACLV to 47.18±6.56% at 20 dah. Changes in the feeding protocol were reflected in feeding preferences (stomach content), and variations of liver lipid content and the occurrence of vacuoles in the intestine. During transition from live prey to artificial feed ( 28 dah), ACLV decreased significantly - indicating amalnutrition period - concomitantwith a delay in the acceptance of artificial feed of 8 days. Thereafter, consumption of artificial feed resulted in an increased ACLV to 56.3±7.6% at 36 dah. The results indicate that during early development meagre is a fast growing species, developing rapidly the structures and basic organs of the digestive system required to overcome successfully the critical stages of larval rearing. The study also shows that histological evaluation of liver lipid content using the ACLV may be a valuable tool incommercial aquaculture to improve larval rearing protocols, and production efficiency. © 2013 Elsevier B.V. |
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. |
Georgakopoulou, E; Loizides, M; Christou, M; Iliopoulou, M; Papadakis, I; Katharios, P; Divanach, P; Koumoundouros, G Thermally-induced phenotypic plasticity in gilthead sea bream. Journal Article Communications in agricultural and applied biological sciences, 78 (4), pp. 143–146, 2013, ISSN: 13791176. @article{georgakopoulou_thermally-induced_2013, title = {Thermally-induced phenotypic plasticity in gilthead sea bream.}, author = {E Georgakopoulou and M Loizides and M Christou and M Iliopoulou and I Papadakis and P Katharios and P Divanach and G Koumoundouros}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84907271903&partnerID=40&md5=fc2e59b41c153fa8c094c3eb304c3191}, issn = {13791176}, year = {2013}, date = {2013-01-01}, journal = {Communications in agricultural and applied biological sciences}, volume = {78}, number = {4}, pages = {143--146}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Papadakis, I E; Papadakis, V M; Glaropoulos, A; Lamprianidou, F; Kentouri, M Escape-related behavior of juvenile gilthead sea bream (Sparus aurata) versus rearing density in experimental conditions Journal Article Journal of Biological Research (Greece), 20 (1), pp. 208–216, 2013, ISSN: 1790045X, (Publisher: BioMed Central Ltd.). @article{papadakis_escape-related_2013, title = {Escape-related behavior of juvenile gilthead sea bream (Sparus aurata) versus rearing density in experimental conditions}, author = {I E Papadakis and V M Papadakis and A Glaropoulos and F Lamprianidou and M Kentouri}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84900003778&partnerID=40&md5=0463e7c38a68523fd20173169374cd04}, issn = {1790045X}, year = {2013}, date = {2013-01-01}, journal = {Journal of Biological Research (Greece)}, volume = {20}, number = {1}, pages = {208--216}, abstract = {Fish escapes from sea cages through net tears have several environmental and economic impacts. The aim of this study was to examine how the rearing density and the condition of the net affect the escape-related behavior of sea bream (Sparus aurata). The trials are performed under control l ed small-scale experiments and continuous video surveillance. Three densities (10, 15 and 20 in dividuals per tank) and three net conditions (a net pen with a tear, a net pen with a cut twine and a flawless net pen) were tested. Sea bream individuals initiate escapes shortly after a tear was created on the net. Altering the number of fish confined in tanks resulted into an exponential increase of the escape rate. Variations on fish interactions towards the net pen were also found and were associated with both rearing density and the condition of the net. Particularly, sea bream in creased net inspection and biting in relation with the rearing density. Additionally, sea bream was further attracted by damages on the net pen, while individuals were capable of extending existing damages. Results presented were statistically significant and could act as recommendations to improve the rearing process protocols.}, note = {Publisher: BioMed Central Ltd.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Fish escapes from sea cages through net tears have several environmental and economic impacts. The aim of this study was to examine how the rearing density and the condition of the net affect the escape-related behavior of sea bream (Sparus aurata). The trials are performed under control l ed small-scale experiments and continuous video surveillance. Three densities (10, 15 and 20 in dividuals per tank) and three net conditions (a net pen with a tear, a net pen with a cut twine and a flawless net pen) were tested. Sea bream individuals initiate escapes shortly after a tear was created on the net. Altering the number of fish confined in tanks resulted into an exponential increase of the escape rate. Variations on fish interactions towards the net pen were also found and were associated with both rearing density and the condition of the net. Particularly, sea bream in creased net inspection and biting in relation with the rearing density. Additionally, sea bream was further attracted by damages on the net pen, while individuals were capable of extending existing damages. Results presented were statistically significant and could act as recommendations to improve the rearing process protocols. |
2012 |
Glaropoulos, Alexios; Papadakis, Vassilis M; Papadakis, Ioannis E; Kentouri, Maroudio Escape-related behavior and coping ability of sea bream due to food supply Journal Article Aquaculture International, 20 (5), pp. 965–979, 2012, ISSN: 0967-6120, 1573-143X. @article{glaropoulos_escape-related_2012, title = {Escape-related behavior and coping ability of sea bream due to food supply}, author = {Alexios Glaropoulos and Vassilis M Papadakis and Ioannis E Papadakis and Maroudio Kentouri}, url = {http://link.springer.com/10.1007/s10499-012-9521-9}, doi = {10.1007/s10499-012-9521-9}, issn = {0967-6120, 1573-143X}, year = {2012}, date = {2012-10-01}, urldate = {2020-08-18}, journal = {Aquaculture International}, volume = {20}, number = {5}, pages = {965--979}, abstract = {Escape of fish is a significant problem for the sustainability of the aquaculture industry. In the Mediterranean Sea, sea bream (Sparus aurata) has been reported to escape from sea cage installations. However, the related factors leading to this behavior still remain unknown. This study focuses on the impact that the food supplied to sea bream has on its interaction with the net and therefore its escape behavior. We test three food ratios (2, 1 and 0 % of the total initial body weight; FC2, FC1 and FC0 populations, respectively) and three different conditions of the net (flawless mesh, mesh with a cut twine and mesh with a tear) that are commonly found in aquaculture. Data acquisition and analysis are carried out with a tailor-made system developed in our laboratory for this purpose. We demonstrate that food supply is associated with fish interactions and the aquaculture net, while net condition is also an important stimulus for sea bream inspection and biting the net. Limited-fed fish (FC1) are more prone to interact with the net, which consequently leads them to either bite net wears or escape through tears. © 2012 Springer Science+Business Media B.V.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Escape of fish is a significant problem for the sustainability of the aquaculture industry. In the Mediterranean Sea, sea bream (Sparus aurata) has been reported to escape from sea cage installations. However, the related factors leading to this behavior still remain unknown. This study focuses on the impact that the food supplied to sea bream has on its interaction with the net and therefore its escape behavior. We test three food ratios (2, 1 and 0 % of the total initial body weight; FC2, FC1 and FC0 populations, respectively) and three different conditions of the net (flawless mesh, mesh with a cut twine and mesh with a tear) that are commonly found in aquaculture. Data acquisition and analysis are carried out with a tailor-made system developed in our laboratory for this purpose. We demonstrate that food supply is associated with fish interactions and the aquaculture net, while net condition is also an important stimulus for sea bream inspection and biting the net. Limited-fed fish (FC1) are more prone to interact with the net, which consequently leads them to either bite net wears or escape through tears. © 2012 Springer Science+Business Media B.V. |
Papadakis, V M; Papadakis, I E; Lamprianidou, F; Glaropoulos, A; Kentouri, M A computer-vision system and methodology for the analysis of fish behavior Journal Article Aquacultural Engineering, 46 , pp. 53 – 59, 2012. @article{papadakis_computer-vision_2012, title = {A computer-vision system and methodology for the analysis of fish behavior}, author = {V M Papadakis and I E Papadakis and F Lamprianidou and A Glaropoulos and M Kentouri}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84855192751&partnerID=40&md5=e60e2fd6dc0176b1dc7506ce2c2763dd}, doi = {10.1016/j.aquaeng.2011.11.002}, year = {2012}, date = {2012-01-01}, journal = {Aquacultural Engineering}, volume = {46}, pages = {53 -- 59}, abstract = {Behavioral variations of small fish populations are difficult to measure quantitatively. To quantify such measurements, a low-cost computer vision system has been developed to analyze fish behavior in aquaculture tanks. With this system, 9 tanks can be observed simultaneously, enabling the study of one factor, in three triplets for further statistical analysis. The system enables the observation of the tanks at all times, with the use of a web publishing tool, while it allows the remote control of the acquisition to eliminate behavioral variations that might otherwise be caused by human presence. Evaluation of the system was achieved by measuring fish interaction (inspection and biting) on three different net conditions. Measurements were completed in three experimental sets, using stocking density as a stress factor. Results clearly demonstrate that the system successfully recorded fish behavior with minimal frame loss (textless21. s in 24. h), while analysis identified every fish interaction with the net. In addition, the measured variations of fish behavior within a single day showed no statistical differences. In conclusion, an inexpensive and efficient computer vision system is presented, assisting in the monitoring and analysis of fish behavior. © 2011 Elsevier B.V.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Behavioral variations of small fish populations are difficult to measure quantitatively. To quantify such measurements, a low-cost computer vision system has been developed to analyze fish behavior in aquaculture tanks. With this system, 9 tanks can be observed simultaneously, enabling the study of one factor, in three triplets for further statistical analysis. The system enables the observation of the tanks at all times, with the use of a web publishing tool, while it allows the remote control of the acquisition to eliminate behavioral variations that might otherwise be caused by human presence. Evaluation of the system was achieved by measuring fish interaction (inspection and biting) on three different net conditions. Measurements were completed in three experimental sets, using stocking density as a stress factor. Results clearly demonstrate that the system successfully recorded fish behavior with minimal frame loss (textless21. s in 24. h), while analysis identified every fish interaction with the net. In addition, the measured variations of fish behavior within a single day showed no statistical differences. In conclusion, an inexpensive and efficient computer vision system is presented, assisting in the monitoring and analysis of fish behavior. © 2011 Elsevier B.V. |
2011 |
Doxa, Chrisa K; Papadakis, Ioannis E; Divanach, Pascal; Kentouri, Maroudio Aquaculture Research, 42 (11), pp. 1623–1631, 2011, ISSN: 1355557X. @article{doxa_effect_2011, title = {Effect of feeding delay after self-feeder activation on growth performance and feeding behaviour of red porgy (Pagrus pagrus L. 1758): application to submergible cages with surface hopper: Feeding behaviour of red porgy}, author = {Chrisa K Doxa and Ioannis E Papadakis and Pascal Divanach and Maroudio Kentouri}, url = {http://doi.wiley.com/10.1111/j.1365-2109.2010.02753.x}, doi = {10.1111/j.1365-2109.2010.02753.x}, issn = {1355557X}, year = {2011}, date = {2011-10-01}, urldate = {2020-08-18}, journal = {Aquaculture Research}, volume = {42}, number = {11}, pages = {1623--1631}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
2009 |
Chatzifotis, S; Arias, M V; Papadakis, I E; Divanach, P Evaluation of feed stimulants in diets for sea bream (Sparus aurata) Journal Article Israeli Journal of Aquaculture - Bamidgeh, 61 (4), pp. 315–321, 2009, ISSN: 0792156X. @article{chatzifotis_evaluation_2009, title = {Evaluation of feed stimulants in diets for sea bream (Sparus aurata)}, author = {S Chatzifotis and M V Arias and I E Papadakis and P Divanach}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-75649099386&partnerID=40&md5=bc0d7bc111cad49326e8f8416ddf1524}, issn = {0792156X}, year = {2009}, date = {2009-01-01}, journal = {Israeli Journal of Aquaculture - Bamidgeh}, volume = {61}, number = {4}, pages = {315--321}, abstract = {Six isoprotein and isolipidic diets were formulated to investigate the effect of dietary additives on growth and feed efficiency of sea bream (Sparus aurata) fry fed a fishmeal-based diet for 80 days. The additives (protorsan, hydrolyzed fish protein, squid meal, krill meal, and betaine + inosine-5'- monophosphate) were added to the diets at the expense of fishmeal. The specific growth rates of the fish ranged from 2.17-2.18% per day for the protorsan and control groups to 2.42% per day for the group fed the squid additive. Significant differences (ptextless0.05) in final body weight and specific growth rate were detected only between the protorsan and control groups and the squid additive group. The feed conversion ratio ranged from 1.04 in the group fed hydrolyzed fish protein group to 1.24 in the group fed krill with no statistically significant differences (ptextgreater0.05) between treatments. The feed stimulating action of taurine was tested by observation. Pellets coated in a taurine solution were more actively consumed than control pellets during the morning feeding but consumption did not differ during the afternoon feeding.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Six isoprotein and isolipidic diets were formulated to investigate the effect of dietary additives on growth and feed efficiency of sea bream (Sparus aurata) fry fed a fishmeal-based diet for 80 days. The additives (protorsan, hydrolyzed fish protein, squid meal, krill meal, and betaine + inosine-5'- monophosphate) were added to the diets at the expense of fishmeal. The specific growth rates of the fish ranged from 2.17-2.18% per day for the protorsan and control groups to 2.42% per day for the group fed the squid additive. Significant differences (ptextless0.05) in final body weight and specific growth rate were detected only between the protorsan and control groups and the squid additive group. The feed conversion ratio ranged from 1.04 in the group fed hydrolyzed fish protein group to 1.24 in the group fed krill with no statistically significant differences (ptextgreater0.05) between treatments. The feed stimulating action of taurine was tested by observation. Pellets coated in a taurine solution were more actively consumed than control pellets during the morning feeding but consumption did not differ during the afternoon feeding. |
Papadakis, I E; Zaiss, M M; Kyriakou, Y; Georgiou, G; Divanach, P; Mylonas, C C Aquaculture, 286 (1-2), pp. 45–52, 2009, ISSN: 00448486. @article{papadakis_histological_2009, title = {Histological evaluation of the elimination of Artemia nauplii from larval rearing protocols on the digestive system ontogeny of shi drum (Umbrina cirrosa L.)}, author = {I E Papadakis and M M Zaiss and Y Kyriakou and G Georgiou and P Divanach and C C Mylonas}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-56649095808&doi=10.1016%2fj.aquaculture.2008.08.028&partnerID=40&md5=98c4d0d5f556cfa435dead4371ff509a}, doi = {10.1016/j.aquaculture.2008.08.028}, issn = {00448486}, year = {2009}, date = {2009-01-01}, journal = {Aquaculture}, volume = {286}, number = {1-2}, pages = {45--52}, abstract = {The influence of the absence of Artemia nauplii from larval diet protocols on growth and digestive system ontogeny was studied using histological techniques in the shi drum (Umbrina cirrosa). One group of larvae was reared using the standard intensive rearing protocol, which offers a combination of enriched rotifers (Brachionus plicatilis), Artemia spp. nauplii and artificial diet (Std-group). Another group was reared using the same protocol, but without the offering of Artemia nauplii (group No-Artemia). The ontogenesis of the digestive system from hatching to metamorphosis was a very rapid process, and there were no differences between the two feeding regimes in the temporal appearance of the various components of the digestive system. The first organised presence of the hepatic and pancreatic tissue appeared at 2-3 d after hatching (dah), suggesting that these organs function from a very early developmental stage. In the No-Artemia larvae between 13 and 29 dah there was a reduction in the height of enterocytes in the intestinal mucosa, a progressive flattening of the primary intestinal folds in the anterior and posterior intestine and a decrease in lipid stores in the liver, suggesting a period of relative starvation. However, by the end of the study at 41 dah, there were no significant differences in body length, intestinal morphology or liver lipid stores between larvae reared under the two feeding regimes. The study suggests that the diet may influence the maturation and/or function, but not the ontogeny of the digestive system. Furthermore, the rapid differentiation of the digestive system in shi drum and the prompt recovery of the No-Artemia larvae from the symptoms of starvation by 29 dah, indicate a plasticity during ontogenesis and the ability of larvae to adapt to artificial diets at very early developmental stages. © 2008 Elsevier B.V. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The influence of the absence of Artemia nauplii from larval diet protocols on growth and digestive system ontogeny was studied using histological techniques in the shi drum (Umbrina cirrosa). One group of larvae was reared using the standard intensive rearing protocol, which offers a combination of enriched rotifers (Brachionus plicatilis), Artemia spp. nauplii and artificial diet (Std-group). Another group was reared using the same protocol, but without the offering of Artemia nauplii (group No-Artemia). The ontogenesis of the digestive system from hatching to metamorphosis was a very rapid process, and there were no differences between the two feeding regimes in the temporal appearance of the various components of the digestive system. The first organised presence of the hepatic and pancreatic tissue appeared at 2-3 d after hatching (dah), suggesting that these organs function from a very early developmental stage. In the No-Artemia larvae between 13 and 29 dah there was a reduction in the height of enterocytes in the intestinal mucosa, a progressive flattening of the primary intestinal folds in the anterior and posterior intestine and a decrease in lipid stores in the liver, suggesting a period of relative starvation. However, by the end of the study at 41 dah, there were no significant differences in body length, intestinal morphology or liver lipid stores between larvae reared under the two feeding regimes. The study suggests that the diet may influence the maturation and/or function, but not the ontogeny of the digestive system. Furthermore, the rapid differentiation of the digestive system in shi drum and the prompt recovery of the No-Artemia larvae from the symptoms of starvation by 29 dah, indicate a plasticity during ontogenesis and the ability of larvae to adapt to artificial diets at very early developmental stages. © 2008 Elsevier B.V. All rights reserved. |
Mylonas, C C; Pavlidis, M; Papandroulakis, N; Zaiss, M M; Tsafarakis, D; Papadakis, I E; Varsamos, S Growth performance and osmoregulation in the shi drum (Umbrina cirrosa) adapted to different environmental salinities Journal Article Aquaculture, 287 (1-2), pp. 203–210, 2009, ISSN: 00448486. @article{mylonas_growth_2009, title = {Growth performance and osmoregulation in the shi drum (Umbrina cirrosa) adapted to different environmental salinities}, author = {C C Mylonas and M Pavlidis and N Papandroulakis and M M Zaiss and D Tsafarakis and I E Papadakis and S Varsamos}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-58049194052&doi=10.1016%2fj.aquaculture.2008.10.024&partnerID=40&md5=a637928fdea05d4d7f37eda6ccf92d9c}, doi = {10.1016/j.aquaculture.2008.10.024}, issn = {00448486}, year = {2009}, date = {2009-01-01}, journal = {Aquaculture}, volume = {287}, number = {1-2}, pages = {203--210}, abstract = {In order to investigate the ability of shi drum (Umbrina cirrosa) to be reared at diverse locations, growth and osmoregulatory performance were assessed at full-strength seawater (40 psu), nearly iso-osmotic water (10 psu) and low salinity water (4 psu). At the end of the 84-day experimental period, fish reared at 4 psu displayed shorter mean fork length, lower mean body weight, lower specific growth rate and higher food conversion efficiency than fish reared at 10 or 40 psu. The effect of salinity on growth performance was also reflected by changes in plasma triglycerides and cholesterol, with fish reared at 4 psu exhibiting the lowest mean concentrations, while there was no significant difference in mean plasma glucose concentrations among treatments. Plasma osmolality was lower at 4 psu from day 42 onwards, while there was no significant difference in mean plasma K+ and Cl- concentrations. Plasma sodium and gill Na+/K+-ATPase activity showed minimum values on day 42 at 4 psu, but at the end of the experiment there was no difference among groups. Pavement cells, mucus cells and chloride cells were identified by histology on the gill epithelium. In shi drum reared at full seawater, mucus cells contained a mixture of acid and neutral mucins, whereas in fish adapted to hypo-osmotic environment neutral mucins were mainly observed. There was a significant increase in chloride cell number over the course of the study in all fish, but there was no difference among the three experimental salinities. Finally, in fish reared at 40 psu salinity, chloride cells increased in size significantly compared to fish adapted to 4 psu, whereas at 10 psu after 42 d there was a significant reduction in chloride cell size. These results indicate that shi drum reared from full-strength seawater to iso-osmotic salinity do not face any osmoregulatory imbalance, while fish reared in hypo-osmotic water displayed osmoregulatory impairment and low growth performance. © 2008 Elsevier B.V. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In order to investigate the ability of shi drum (Umbrina cirrosa) to be reared at diverse locations, growth and osmoregulatory performance were assessed at full-strength seawater (40 psu), nearly iso-osmotic water (10 psu) and low salinity water (4 psu). At the end of the 84-day experimental period, fish reared at 4 psu displayed shorter mean fork length, lower mean body weight, lower specific growth rate and higher food conversion efficiency than fish reared at 10 or 40 psu. The effect of salinity on growth performance was also reflected by changes in plasma triglycerides and cholesterol, with fish reared at 4 psu exhibiting the lowest mean concentrations, while there was no significant difference in mean plasma glucose concentrations among treatments. Plasma osmolality was lower at 4 psu from day 42 onwards, while there was no significant difference in mean plasma K+ and Cl- concentrations. Plasma sodium and gill Na+/K+-ATPase activity showed minimum values on day 42 at 4 psu, but at the end of the experiment there was no difference among groups. Pavement cells, mucus cells and chloride cells were identified by histology on the gill epithelium. In shi drum reared at full seawater, mucus cells contained a mixture of acid and neutral mucins, whereas in fish adapted to hypo-osmotic environment neutral mucins were mainly observed. There was a significant increase in chloride cell number over the course of the study in all fish, but there was no difference among the three experimental salinities. Finally, in fish reared at 40 psu salinity, chloride cells increased in size significantly compared to fish adapted to 4 psu, whereas at 10 psu after 42 d there was a significant reduction in chloride cell size. These results indicate that shi drum reared from full-strength seawater to iso-osmotic salinity do not face any osmoregulatory imbalance, while fish reared in hypo-osmotic water displayed osmoregulatory impairment and low growth performance. © 2008 Elsevier B.V. All rights reserved. |
2008 |
Chatzifotis, S; Kokou, F; Ampatzis, K; Papadakis, I E; Divanach, P; Dermon, C R Aquaculture Nutrition, 14 (5), pp. 405–415, 2008, ISSN: 13535773. @article{chatzifotis_effects_2008, title = {Effects of dietary caffeine on growth, body composition, somatic indexes, and cerebral distribution of acetyl-cholinesterase and nitric oxide synthase in gilthead sea bream (Sparus aurata), reared in winter temperature}, author = {S Chatzifotis and F Kokou and K Ampatzis and I E Papadakis and P Divanach and C R Dermon}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-51349164015&doi=10.1111%2fj.1365-2095.2007.00541.x&partnerID=40&md5=5b17b1a62bdf3d88373fd728afada0b0}, doi = {10.1111/j.1365-2095.2007.00541.x}, issn = {13535773}, year = {2008}, date = {2008-01-01}, journal = {Aquaculture Nutrition}, volume = {14}, number = {5}, pages = {405--415}, abstract = {This study aims at examining the effect of caffeine administration on growth, feed efficiency, and consumption of sea bream (Sparus aurata), reared in winter temperatures. Moreover, it is questioned whether caffeine has a central action in the brain and its effects are partly mediated via central brain mechanisms. For this, we studied the influences of caffeine treatment on the cerebral pattern of the cholinergic neurotransmission and the novel neuromodulator nitric oxide (NO), by means of acetyl-cholinesterase (AchE) and nitric oxide synthase (NOS) histochemistry. Five different diets containing 0.0, 0.1, 1.0, 2.0 and 5.0 g caffeine kg-1 of diet were administrated to five groups of fish. Caffeine adversely affected sea-bream growth at a concentration higher than 1 g kg-1 diet and increased feed conversion ratio in the treatments of 2 and 5 g kg-1 (P < 0.05). The daily consumption of feeds was similar to all groups, indicating that caffeine did not influence diet palatability. AChE- and NADPH-diaphorase histochemistry showed densely labeled cells and fibers mainly in dorsal telencephalon, preoptic, pretectal, hypothalamic areas, optic tectum, reticular formation, cerebellum and motor nuclei. When compared with matched caffeine-treated animals, no differences in the histochemical pattern and cell densities of cerebral AChE and NADPH-diaphorase were found. © 2008 Blackwell Publishing Ltd.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This study aims at examining the effect of caffeine administration on growth, feed efficiency, and consumption of sea bream (Sparus aurata), reared in winter temperatures. Moreover, it is questioned whether caffeine has a central action in the brain and its effects are partly mediated via central brain mechanisms. For this, we studied the influences of caffeine treatment on the cerebral pattern of the cholinergic neurotransmission and the novel neuromodulator nitric oxide (NO), by means of acetyl-cholinesterase (AchE) and nitric oxide synthase (NOS) histochemistry. Five different diets containing 0.0, 0.1, 1.0, 2.0 and 5.0 g caffeine kg-1 of diet were administrated to five groups of fish. Caffeine adversely affected sea-bream growth at a concentration higher than 1 g kg-1 diet and increased feed conversion ratio in the treatments of 2 and 5 g kg-1 (P < 0.05). The daily consumption of feeds was similar to all groups, indicating that caffeine did not influence diet palatability. AChE- and NADPH-diaphorase histochemistry showed densely labeled cells and fibers mainly in dorsal telencephalon, preoptic, pretectal, hypothalamic areas, optic tectum, reticular formation, cerebellum and motor nuclei. When compared with matched caffeine-treated animals, no differences in the histochemical pattern and cell densities of cerebral AChE and NADPH-diaphorase were found. © 2008 Blackwell Publishing Ltd. |
Papadakis, I E; Chatzifotis, S; Divanach, P; Kentouri, M Weaning of greater amberjack (Seriola dumerilii Risso 1810) juveniles from moist to dry pellet Journal Article Aquaculture International, 16 (1), pp. 13–25, 2008, ISSN: 09676120. @article{papadakis_weaning_2008, title = {Weaning of greater amberjack (Seriola dumerilii Risso 1810) juveniles from moist to dry pellet}, author = {I E Papadakis and S Chatzifotis and P Divanach and M Kentouri}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-38149134529&doi=10.1007%2fs10499-007-9118-x&partnerID=40&md5=7a53d9f9573132c2ddb1145ec1d41d32}, doi = {10.1007/s10499-007-9118-x}, issn = {09676120}, year = {2008}, date = {2008-01-01}, journal = {Aquaculture International}, volume = {16}, number = {1}, pages = {13--25}, abstract = {The weaning of greater amberjack (Seriola dumerilii Risso 1810) to a dry diet was studied in two consecutive experiments. The experimental fish were hatchery-produced and grown to their initial size on a soft pellet containing 50% trash fish and 50% commercial dry pellet. In the first experiment, three homogenous groups of greater amberjacks (n = 153, mean weight: 374 ± 43 g), initially adapted for a period of 30 days to a diet with a 40% moisture content, were fed on commercial pellets containing three different levels of dietary moisture (7, 20 and 40%, respectively) for 126 days. We found that fish needed a month to adapt to the 7%- and 20%-moisture diets and that moisture content of the diet had a significant effect on fish growth in terms of increasing feed consumption and lowering feed conversion ratio. The group fed on the 20%-moisture diet not only compensated for the initial adaptation period but presented the higher growth rate and best feed conversion ratio. In the second experiment, all groups of experiment 1 were fed the same commercial diet with a 7% moisture content for 72 days. The group that had been previously fed on the 20%-moisture diet showed the best growth performance. The implication of the above results for the weaning of greater amberjack to dry diets is discussed in terms of the digestion process and physiology. © Springer Science+Business Media B.V. 2007.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The weaning of greater amberjack (Seriola dumerilii Risso 1810) to a dry diet was studied in two consecutive experiments. The experimental fish were hatchery-produced and grown to their initial size on a soft pellet containing 50% trash fish and 50% commercial dry pellet. In the first experiment, three homogenous groups of greater amberjacks (n = 153, mean weight: 374 ± 43 g), initially adapted for a period of 30 days to a diet with a 40% moisture content, were fed on commercial pellets containing three different levels of dietary moisture (7, 20 and 40%, respectively) for 126 days. We found that fish needed a month to adapt to the 7%- and 20%-moisture diets and that moisture content of the diet had a significant effect on fish growth in terms of increasing feed consumption and lowering feed conversion ratio. The group fed on the 20%-moisture diet not only compensated for the initial adaptation period but presented the higher growth rate and best feed conversion ratio. In the second experiment, all groups of experiment 1 were fed the same commercial diet with a 7% moisture content for 72 days. The group that had been previously fed on the 20%-moisture diet showed the best growth performance. The implication of the above results for the weaning of greater amberjack to dry diets is discussed in terms of the digestion process and physiology. © Springer Science+Business Media B.V. 2007. |
Micale, V; Giancamillo, Di A; Domeneghini, C; Mylonas, C C; Nomikos, N; Papadakis, I E; Muglia, U Ontogeny of the digestive tract in sharpsnout sea bream Diplodus puntazzo (Cetti, 1777) Journal Article Histology and Histopathology, 23 (9), pp. 1077–1091, 2008, ISSN: 02133911. @article{micale_ontogeny_2008, title = {Ontogeny of the digestive tract in sharpsnout sea bream Diplodus puntazzo (Cetti, 1777)}, author = {V Micale and A Di Giancamillo and C Domeneghini and C C Mylonas and N Nomikos and I E Papadakis and U Muglia}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84863988830&partnerID=40&md5=176459c6664c6e794375b702ca2d412e}, issn = {02133911}, year = {2008}, date = {2008-01-01}, journal = {Histology and Histopathology}, volume = {23}, number = {9}, pages = {1077--1091}, abstract = {The ontogeny of the digestive tract was studied histologically and histochemically in sharpsnout sea bream Diplodus puntazzo from hatching (0 DAH, Days After Hatching) until day 57 (57 DAH). At hatching, the digestive tract appeared as a histologically undifferentiated straight tube lying dorsally to the yolk sac. When the mouth opened at 3 DAH, the digestive tract was differentiated into buccopharynx, oesophagus, incipient stomach and intestine. The pancreas, liver and gall bladder were also differentiated at this stage and both the bile and pancreatic duct had opened into the anterior intestine. Active feeding began in 50% of larvae at 4 DAH, although permanence of yolk reserves until 7 DAH suggests a period of both endogenous and exogenous feeding. Nutrient absorption was first visible from 5 DAH, as colourless supra- and infranuclear vacuoles in the anterior intestinal mucosa, suggesting a lipid content, as well as supranuclear, eosinophilic vacuoles, containing protein, in the posterior intestinal mucosa. Early caecal development could be detected from 10 DAH, whereas gastric glands appeared at 30 DAH, indicating the transition from larval to juvenile stage and the acquisition of an adult mode of digestion. Goblet cells appeared in the digestive tract of sharpsnout sea bream larvae shortly after first feeding. The mucus content of goblet cells varied with the digestive region and, in the buccal cavity and oesophagus, also with the developmental phase. This study provides knowledge for better husbandry practices in the aquaculture industry, as well as for the implementation of future nutritional studies.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The ontogeny of the digestive tract was studied histologically and histochemically in sharpsnout sea bream Diplodus puntazzo from hatching (0 DAH, Days After Hatching) until day 57 (57 DAH). At hatching, the digestive tract appeared as a histologically undifferentiated straight tube lying dorsally to the yolk sac. When the mouth opened at 3 DAH, the digestive tract was differentiated into buccopharynx, oesophagus, incipient stomach and intestine. The pancreas, liver and gall bladder were also differentiated at this stage and both the bile and pancreatic duct had opened into the anterior intestine. Active feeding began in 50% of larvae at 4 DAH, although permanence of yolk reserves until 7 DAH suggests a period of both endogenous and exogenous feeding. Nutrient absorption was first visible from 5 DAH, as colourless supra- and infranuclear vacuoles in the anterior intestinal mucosa, suggesting a lipid content, as well as supranuclear, eosinophilic vacuoles, containing protein, in the posterior intestinal mucosa. Early caecal development could be detected from 10 DAH, whereas gastric glands appeared at 30 DAH, indicating the transition from larval to juvenile stage and the acquisition of an adult mode of digestion. Goblet cells appeared in the digestive tract of sharpsnout sea bream larvae shortly after first feeding. The mucus content of goblet cells varied with the digestive region and, in the buccal cavity and oesophagus, also with the developmental phase. This study provides knowledge for better husbandry practices in the aquaculture industry, as well as for the implementation of future nutritional studies. |
2006 |
Sfakianakis, D G; Georgakopoulou, E; Papadakis, I E; Divanach, P; Kentouri, M; Koumoundouros, G Environmental determinants of haemal lordosis in European sea bass, Dicentrarchus labrax (Linnaeus, 1758) Journal Article Aquaculture, 254 (1-4), pp. 54–64, 2006, ISSN: 00448486. @article{sfakianakis_environmental_2006, title = {Environmental determinants of haemal lordosis in European sea bass, Dicentrarchus labrax (Linnaeus, 1758)}, author = {D G Sfakianakis and E Georgakopoulou and I E Papadakis and P Divanach and M Kentouri and G Koumoundouros}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0044848605006332}, doi = {10.1016/j.aquaculture.2005.10.028}, issn = {00448486}, year = {2006}, date = {2006-04-01}, urldate = {2020-08-18}, journal = {Aquaculture}, volume = {254}, number = {1-4}, pages = {54--64}, abstract = {We tested the effect of water-temperature during the larval phase on sea bass sensitivity to current-induced lordosis. During larval rearing phase, fish were subjected to two different water temperatures (15 or 20 °C), with the rest of the rearing parameters remaining identical between the different populations. During the pregrowing phase, the different populations were subjected to four different water-current velocities (WCV), with the rest of the environmental conditions remaining common. At the end of the pregrowing phase (43.5 ± 0.8 mm TL), lordosis was more frequent in fish that developed at 20 °C (p textless 0.05), independently of the WCVs applied. The anatomic analysis of the deformed fish revealed a significant effect of early developmental temperature on the severity of the deformity, with the 15 °C populations showing the lower severity in respect to the angle of lordosis and the number of affected vertebrae (p textless 0.05). Two weeks of exposure to WCVs (24.0 ± 0.8 mm TL) resulted in 15 °C populations presenting the lower incidence of lordosis and the higher incidence of normal fish in all WCVs, except 50%, tested (p textless 0.05). At this stage, WCV had a clear effect on lordosis development in populations coming from both developmental temperatures (p textless 0.05), although at 15 °C these effects were more pronounced. Fish that developed at 20 °C showed significantly higher incidence of deformed vertebral centra and arches than those developed at 15 °C (p textless 0.05). These early anatomical signs were evident in samples taken at the end of the larval rearing phase (15.7 ± 1.0 mm TL), as well as 1 week after the onset of exposure to WCVs (21.4 ± 0.6 mm TL). In both cases, their incidence was significantly higher in fish that initially developed at 20 °C than at 15 °C. © 2005 Elsevier B.V. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We tested the effect of water-temperature during the larval phase on sea bass sensitivity to current-induced lordosis. During larval rearing phase, fish were subjected to two different water temperatures (15 or 20 °C), with the rest of the rearing parameters remaining identical between the different populations. During the pregrowing phase, the different populations were subjected to four different water-current velocities (WCV), with the rest of the environmental conditions remaining common. At the end of the pregrowing phase (43.5 ± 0.8 mm TL), lordosis was more frequent in fish that developed at 20 °C (p textless 0.05), independently of the WCVs applied. The anatomic analysis of the deformed fish revealed a significant effect of early developmental temperature on the severity of the deformity, with the 15 °C populations showing the lower severity in respect to the angle of lordosis and the number of affected vertebrae (p textless 0.05). Two weeks of exposure to WCVs (24.0 ± 0.8 mm TL) resulted in 15 °C populations presenting the lower incidence of lordosis and the higher incidence of normal fish in all WCVs, except 50%, tested (p textless 0.05). At this stage, WCV had a clear effect on lordosis development in populations coming from both developmental temperatures (p textless 0.05), although at 15 °C these effects were more pronounced. Fish that developed at 20 °C showed significantly higher incidence of deformed vertebral centra and arches than those developed at 15 °C (p textless 0.05). These early anatomical signs were evident in samples taken at the end of the larval rearing phase (15.7 ± 1.0 mm TL), as well as 1 week after the onset of exposure to WCVs (21.4 ± 0.6 mm TL). In both cases, their incidence was significantly higher in fish that initially developed at 20 °C than at 15 °C. © 2005 Elsevier B.V. All rights reserved. |
Zaiss, M M; Papadakis, I E; Maingot, E; Divanach, P; Mylonas, C C Ontogeny of the digestive tract in shi drum (Umbrina cirrosa L.) reared using the mesocosm larval rearing system Journal Article Aquaculture, 260 (1-4), pp. 357–368, 2006, ISSN: 00448486. @article{zaiss_ontogeny_2006, title = {Ontogeny of the digestive tract in shi drum (Umbrina cirrosa L.) reared using the mesocosm larval rearing system}, author = {M M Zaiss and I E Papadakis and E Maingot and P Divanach and C C Mylonas}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-33747800319&doi=10.1016%2fj.aquaculture.2006.06.001&partnerID=40&md5=4f7c6eb4f3932426b7e5fb62cafa6f95}, doi = {10.1016/j.aquaculture.2006.06.001}, issn = {00448486}, year = {2006}, date = {2006-01-01}, journal = {Aquaculture}, volume = {260}, number = {1-4}, pages = {357--368}, abstract = {Histological changes of the digestive tract were studied in shi drum (Umbrina cirrosa) from hatching until 41 days post hatching (dph), when the fry had a mean (±S.D.) total length (TL) of 32 ± 2 mm and wet weight (WW) of 0.42 ± 0.07 g. Larvae were reared using the mesocosm technique, the most natural among commercially employed rearing methods for marine larvae. Shi drum opened their mouth at 2 dph (2.78 ± 0.09 mm TL), at which time 90% of the larvae already had an inflated swim bladder. The differentiation of the digestive tract into buccopharynx, esophagus, and anterior and posterior intestine was completed by 3 dph (2.82 ± 0.07 mm TL), 1 day after the onset of exogenous feeding. The alimentary canal started coiling and formed its first loop at 2 dph, while the pancreas and liver were differentiated at 3 dph. Yolk sac reserves lasted until 7 dph (4.3 ± 0.1 mm TL), suggesting a brief period of endogenous and exogenous feeding. The first esophageal goblet cells appeared at 7 dph containing acid mucins and at 8 dph taste buds appeared on the buccopharyngeal epithelium. The stomach was morphologically differentiated at 9 dph (5.5 ± 0.1 mm TL) when gastric glands became abundant in the cardiac region, and the first pyloric caeca appeared at 14 dph (10.1 ± 0.9 mm TL). Supranuclear eosinophilic vacuoles were observed in the posterior intestine between 3 and 11 dph (6.3 ± 0.9 mm TL). Their number decreased as the stomach differentiated, suggesting a change in the protein digestion mechanism. The results of the study suggest a rapid development of shi drum and its digestive system and underline the possibility of weaning larvae to artificial feed even earlier than the 12 dph employed in the present study. © 2006 Elsevier B.V. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Histological changes of the digestive tract were studied in shi drum (Umbrina cirrosa) from hatching until 41 days post hatching (dph), when the fry had a mean (±S.D.) total length (TL) of 32 ± 2 mm and wet weight (WW) of 0.42 ± 0.07 g. Larvae were reared using the mesocosm technique, the most natural among commercially employed rearing methods for marine larvae. Shi drum opened their mouth at 2 dph (2.78 ± 0.09 mm TL), at which time 90% of the larvae already had an inflated swim bladder. The differentiation of the digestive tract into buccopharynx, esophagus, and anterior and posterior intestine was completed by 3 dph (2.82 ± 0.07 mm TL), 1 day after the onset of exogenous feeding. The alimentary canal started coiling and formed its first loop at 2 dph, while the pancreas and liver were differentiated at 3 dph. Yolk sac reserves lasted until 7 dph (4.3 ± 0.1 mm TL), suggesting a brief period of endogenous and exogenous feeding. The first esophageal goblet cells appeared at 7 dph containing acid mucins and at 8 dph taste buds appeared on the buccopharyngeal epithelium. The stomach was morphologically differentiated at 9 dph (5.5 ± 0.1 mm TL) when gastric glands became abundant in the cardiac region, and the first pyloric caeca appeared at 14 dph (10.1 ± 0.9 mm TL). Supranuclear eosinophilic vacuoles were observed in the posterior intestine between 3 and 11 dph (6.3 ± 0.9 mm TL). Their number decreased as the stomach differentiated, suggesting a change in the protein digestion mechanism. The results of the study suggest a rapid development of shi drum and its digestive system and underline the possibility of weaning larvae to artificial feed even earlier than the 12 dph employed in the present study. © 2006 Elsevier B.V. All rights reserved. |
2005 |
Chatzifotis, S; Papadakis, I E; Divanach, P Effect of dietary water on growth of dentex Dentex dentex Journal Article Fisheries Science, 71 (6), pp. 1243–1248, 2005, ISSN: 09199268. @article{chatzifotis_effect_2005, title = {Effect of dietary water on growth of dentex Dentex dentex}, author = {S Chatzifotis and I E Papadakis and P Divanach}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-31144439969&doi=10.1111%2fj.1444-2906.2005.01089.x&partnerID=40&md5=8d72e22c36d27bfa837cdc0365529fd7}, doi = {10.1111/j.1444-2906.2005.01089.x}, issn = {09199268}, year = {2005}, date = {2005-01-01}, journal = {Fisheries Science}, volume = {71}, number = {6}, pages = {1243--1248}, abstract = {This study is concerned with the effect of hyrdated diets on growth and feed performance of Dentex dentex. Three levels of dietary water were tested: 7%, 20% and 40%. For the 7% level a commercial feed was used and the 20% and 40% water levels were obtained after adding an appropriate amount of deionized water to the commercial feed and mixing the pellets well. The diets were offered to fish by self-feeders, by which fish were allowed continuous access to diets after activating the self-feeders; by belt feeders, by which the diets were fed continuously and in excess over a 12 h interval; and by hand to apparent satiation two times a day. After 151 days of feeding, the group fed on the 20%-water diet showed significantly (P textless 0.05) higher growth rate than the 7 and 40% groups, while no significant differences were observed in feed conversion rate or daily feed consumption. The means of feed delivery did not influence growth rate. Self-feeder, belt and hand feeding all gave comparable growth. Fish fed the more condensed 7%-water diet had smaller stomachs than fish fed the larger volume 40%-water diet. In the stomach, all groups of fish hydrated their digesta within 2 h after feeding to a moisture content of around 60%. Apparently no difference in digestive process was observed between groups. It was concluded that the addition of water in diet at the level of 20% has a beneficial effect on dentex growth.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This study is concerned with the effect of hyrdated diets on growth and feed performance of Dentex dentex. Three levels of dietary water were tested: 7%, 20% and 40%. For the 7% level a commercial feed was used and the 20% and 40% water levels were obtained after adding an appropriate amount of deionized water to the commercial feed and mixing the pellets well. The diets were offered to fish by self-feeders, by which fish were allowed continuous access to diets after activating the self-feeders; by belt feeders, by which the diets were fed continuously and in excess over a 12 h interval; and by hand to apparent satiation two times a day. After 151 days of feeding, the group fed on the 20%-water diet showed significantly (P textless 0.05) higher growth rate than the 7 and 40% groups, while no significant differences were observed in feed conversion rate or daily feed consumption. The means of feed delivery did not influence growth rate. Self-feeder, belt and hand feeding all gave comparable growth. Fish fed the more condensed 7%-water diet had smaller stomachs than fish fed the larger volume 40%-water diet. In the stomach, all groups of fish hydrated their digesta within 2 h after feeding to a moisture content of around 60%. Apparently no difference in digestive process was observed between groups. It was concluded that the addition of water in diet at the level of 20% has a beneficial effect on dentex growth. |
Katharios, P; Papadakis, I E; Prapas, A; Dermon, C R; Ampatzis, K; Divanach, P Bulletin of the European Association of Fish Pathologists, 25 (1), pp. 28–31, 2005, ISSN: 01080288. @article{katharios_mortality_2005, title = {Mortality control of viral encephalopathy and retinopathy in 0+ grouper Epinephelus marginatus after prolonged bath in dense Chlorella minutissima culture}, author = {P Katharios and I E Papadakis and A Prapas and C R Dermon and K Ampatzis and P Divanach}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-15744380255&partnerID=40&md5=1882681096115ce168df99dfd0aaf0d8}, issn = {01080288}, year = {2005}, date = {2005-01-01}, journal = {Bulletin of the European Association of Fish Pathologists}, volume = {25}, number = {1}, pages = {28--31}, abstract = {0+ grouper (1±0.2g), presenting symptoms of Viral Encephalopathy and Retinopathy (confirmed by isolation of the virus in SSN-1 cell line and identification by IFAT and DNA sequencing as well as by brain histology), were submitted to seven bath treatment regimes for a 30-day period, using different concentrations of Chlorella minutissima and the antibiotic furaltadone. The cumulative mortalities were 0, 0, 5 and 32% when using 2×108, 108, 5×107 and 2×107 cells of C. minutissima ml-1 respectively, compared to 31-36 % in the control and 55-68% in the antibiotic-treated groups. The beneficial effect, the possible immuno-stimulant and antiviral properties of unicellular micro-algae such as C. minutissima, as well as the role of their concentration in the bath treatment, are discussed.}, keywords = {}, pubstate = {published}, tppubtype = {article} } 0+ grouper (1±0.2g), presenting symptoms of Viral Encephalopathy and Retinopathy (confirmed by isolation of the virus in SSN-1 cell line and identification by IFAT and DNA sequencing as well as by brain histology), were submitted to seven bath treatment regimes for a 30-day period, using different concentrations of Chlorella minutissima and the antibiotic furaltadone. The cumulative mortalities were 0, 0, 5 and 32% when using 2×108, 108, 5×107 and 2×107 cells of C. minutissima ml-1 respectively, compared to 31-36 % in the control and 55-68% in the antibiotic-treated groups. The beneficial effect, the possible immuno-stimulant and antiviral properties of unicellular micro-algae such as C. minutissima, as well as the role of their concentration in the bath treatment, are discussed. |
Koumoundouros, G; Kouttouki, S; Georgakopoulou, E; Papadakis, I; Maingot, E; Kaspiris, P; Kiriakou, Y; Georgiou, G; Divanach, P; Kentouri, M; Mylonas, C C Ontogeny of the shi drum Umbrina cirrosa (Linnaeus 1758), a candidate new species for aquaculture Journal Article Aquaculture Research, 36 (13), pp. 1265–1272, 2005, ISSN: 1355557X. @article{koumoundouros_ontogeny_2005, title = {Ontogeny of the shi drum Umbrina cirrosa (Linnaeus 1758), a candidate new species for aquaculture}, author = {G Koumoundouros and S Kouttouki and E Georgakopoulou and I Papadakis and E Maingot and P Kaspiris and Y Kiriakou and G Georgiou and P Divanach and M Kentouri and C C Mylonas}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-25844487755&doi=10.1111%2fj.1365-2109.2005.01314.x&partnerID=40&md5=e26503abd5c1e3f3b24d5805f8231280}, doi = {10.1111/j.1365-2109.2005.01314.x}, issn = {1355557X}, year = {2005}, date = {2005-01-01}, journal = {Aquaculture Research}, volume = {36}, number = {13}, pages = {1265--1272}, abstract = {The ontogeny of shi drum Umbrina cirrosa (Linnaeus 1758), a candidate new species for aquaculture, was studied throughout the entire larval phase. Geometric morphometric analysis revealed two clear inflection points (7.0 and 12.7 mm total length, TL) in the shape ontogeny of this species, separating the studied period into three phases of different allometric priorities. Spline graphs demonstrated that the major non-uniform shape ontogeny correlated with the development of the fins, the anterior dorsal area of the body, the caudal peduncle, the eye and the mouth. Concerning the morphological features, shi drum larvae are characterized by an upward anterior bending of the notochord. The ontogeny of the fins began with the formation of the pectoral buds (2.9 mm TL), continued with the notochord flexion (4.3 mm TL, associated with the caudal fin development), the appearance of the pelvic buds, the first anal rays (4.5 mm TL) and the first dorsal rays (4.8 mm TL). Shi drum juveniles presented 25 vertebrae and the following dominant fin types: D XI,23, AII,6,VI,5, P17 and C17. © 2005 Blackwell Publishing Ltd.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The ontogeny of shi drum Umbrina cirrosa (Linnaeus 1758), a candidate new species for aquaculture, was studied throughout the entire larval phase. Geometric morphometric analysis revealed two clear inflection points (7.0 and 12.7 mm total length, TL) in the shape ontogeny of this species, separating the studied period into three phases of different allometric priorities. Spline graphs demonstrated that the major non-uniform shape ontogeny correlated with the development of the fins, the anterior dorsal area of the body, the caudal peduncle, the eye and the mouth. Concerning the morphological features, shi drum larvae are characterized by an upward anterior bending of the notochord. The ontogeny of the fins began with the formation of the pectoral buds (2.9 mm TL), continued with the notochord flexion (4.3 mm TL, associated with the caudal fin development), the appearance of the pelvic buds, the first anal rays (4.5 mm TL) and the first dorsal rays (4.8 mm TL). Shi drum juveniles presented 25 vertebrae and the following dominant fin types: D XI,23, AII,6,VI,5, P17 and C17. © 2005 Blackwell Publishing Ltd. |