Turkish Journal of Fisheries and Aquatic Sciences
2014, Vol 14, Num, 3 (Pages: 759-768)
Stage-Specific Ontogeny of Digestive Enzymes in the Cultured Common Dentex (Dentex dentex) Larvae
2 Adnan Menderes University, Faculty of Agriculture, Fisheries and Aquaculture Engineering Department, Aydin, Turkey DOI : 10.4194/1303-2712-v14_3_18 Viewed : 4993 - Downloaded : 3571 Stage-specific ontogeny of main digestive enzymes in common dentex, Dentex dentex, were assayed during early life development according to notochord flexion studied from hatching to 45 days after hatching (DAH). The notochord was straight in yolk-sac larvae of D. dentex and preflexion stage was observed between 0 and 18 DAH as 2.75 and 6.27 mm at total length (TL). Then, flexion of the notochord was estimated between 19 and 30 DAH as 6.27 and 10.9 mm at TL. Important alterations in specific activities of all digestive enzymes measured during period of this study were mostly related with metamorphosis and co-feeding. Trypsin and chymotrypsin specific activities were firstly detected on day 3 and were related with mouth opening, whereas they slightly increased until 25 DAH respectively. Pepsin was firstly detected on day 28 and related with stomach formation and a sharp increase was observed until 30 DAH. Both amylase and lipase were measured on day 2 and 4, respectively and they also sharply increased during the first week of life. Additionally, except pepsin, most of the digestive enzyme activities were firstly secreted in the preflexion stage and also gastric secretion started and functional development digestive system were occurred in in flexion and postflexion stages, respectively. Keywords : Digestive enzymes, stage-specific ontogeny, larval development, Dentex dentex, common dentex