Cahu, C.L., Infante, J.L.Z.-1997
Aquaculture International, 5 (2) : 151-160
Abstract:
Sea bass larvae were fed a compound diet from day 15 or day 25 until day 40. Control larvae were fed Artemia. The digestive capacity of larvae was assessed in the pancreas and in two enterocyte areas, the brush border membrane and the cytosol separately. Trypsin and amylase levels of the pancreatic segment in the weaned groups were similar or higher than those of the control. This suggests that a deficiency in pancreatic enzyme synthesis cannot explain the poor growth of compound diet fed larvae. However, pancreatic secretion was lowered by weaning on the compound diet. A marked decrease in the cytosolic enzyme (leucine alanine peptidase) and a concurrent increase in brush border enzymes (alkaline phosphatase and leucine aminopeptidase) were observed in larvae fed on Artemia. Similar enzymatic variations occurred but with a slight delay in the weaned groups. It is concluded that low endogenous enzyme production is not the cause of poor post weaning growth. The poor growth of weaned larvae may be due rather to an inadequacy of conventional compound diets in meeting larval digestive specificities.
(IFREMER, INRA, Unite Mixte Nutr Poissons, BP 70, F-29280 Plouzane, France)
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