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

TitleOntogeny of the digestive system of meagre Argyrosomus regius reared in a mesocosm, and quantitative changes of lipids in the liver from hatching to juvenile
Publication TypeMiscellaneous
Year of Publication2013
AuthorsPapadakis, IE, Kentouri M, Divanach P, Mylonas CC
Description

Export Date: 18 December 2013Source: ScopusArticle in Pressdoi: 10.1016/j.aquaculture.2013.01.012

KeywordsArgyrosomus regius, Digestive system, Larvae, Liver, Meagre
Abstract

Histological development of the digestive system was studied in association with feeding preferences in meagre (Argyrosomus regius) from hatching to juvenile (44. days after hatching, dah), using a mesocosm system. 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 a malnutrition period - concomitant with 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 in commercial aquaculture to improve larval rearing protocols, and production efficiency. © 2013 Elsevier B.V.

URLhttp://www.scopus.com/inward/record.url?eid=2-s2.0-84873700252&partnerID=40&md5=7c3e500acdcd6ba8b22f5df7a20dece7

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