Differential modulation of digestive enzymes and energy reserves at different times after feeding in juveniles of the marine estuarine-dependent flatfish Paralichthys orbignyanus (Valenciennes, 1839).

Integrative works on the responses of digestive enzymes and energy reserves in conjunction with morphological traits at distinct postprandial times in marine estuarine-dependent flatfishes of ecological and economic importance, such as Paralichthys orbignyanus are lacking. We determined total weight (TW), hepatosomatic index (HSI), digestive enzymes activities in the intestine and energy reserves concentration in liver and muscle at 0, 24, 72 and 360h after feeding in juveniles of P. orbignyanus. Amylase activity decreased at 72h (about 30%). Maltase, sucrase and lipase activities peak increased at 24h (67, 600 and 35%). Trypsin and APN activities at 24 and 72 h, respectively were lower than t = 0 (53 and 30%). A peak increase of glycogen and triglycerides concentration in liver (24h) (86 and 89 %) occurred. In muscle, glycogen and triglycerides concentrations were unchanged at 24h and higher at72 and 360h (100 and 60%). No changes in TW, HSI, free glucose in liver and muscle, and protein in liver were found. The protein concentration in muscle peak increased at 24 and 360 h after feeding (60%). The results indicate a distinct and specific response of central components of carbohydrate, lipid and protein metabolism that could constitute adjustments at the biochemical level upon periods of irregular feeding and even of long-term food privation inside coastal lagoon or estuaries. The distinct responses of digestive enzyme in intestine, and energy reserves in liver and muscle suggest the differential modulation of tissue-specific anabolic and catabolic pathways that would allow the maintenance of physical condition. This article is protected by copyright. All rights reserved.