Influence of dietary live
yeast on European sea bass (Dicentrarchus labrax) larval development
D. Tovar-Ramírez, J. Zambonino Infante, C. Cahu,
F.J. Gatesoupe, R. Vázquez-Juárez-2004
Aquaculture, 234(1-4): 415-427
Abstract:
Recent results have demonstrated that live yeast in
diets improved gut maturation in sea bass larvae. In this study, we tested
the absence and two levels of live yeast in sea bass larvae diets. Specimens
were fed from time of mouth opening to 37 days after hatching a diet of 0%,
1.1%, or 5.7% wet weight of live yeast (Debaryomyces hansenii CBS
8339). Yeast incorporation improved survival 10%, and reduced malformed
larvae. In groups fed 1.1% yeast, only 1% of larvae were malformed, compared
to 14% in the control group. Final mean weight in groups fed 1.1% yeast was
twice that of other groups. Activities and concentrations of mRNA trypsin
and lipase were higher in the two groups fed yeast than in the control
group, whereas activity and concentration of mRNA amylase were lower. This
suggests that the pancreas matured faster in the two groups fed yeast.
Activities of intestinal enzymes alkaline phosphatase, aminopeptidase N, and
maltase in the group fed 1.1% yeast were higher than those in the two other
groups, revealing earlier development of intestinal digestion. The best
results were obtained with the diet containing 1.1% yeast cell biomass,
corresponding approximately to 106 CFU g-1 in the diet
and 1.1×104 CFU per larva 30 days after hatching. The
dose-dependent effect of yeast on rearing performance could be attributed to
the amount of polyamines secreted by live yeast in the gut lumen of larvae.
(Centro de Investigaciones Biológicas del Noroeste
(CIBNOR), Patologia Marina, POB 128, La Paz, BCS CP 23000, Mexico, e-mail: dtovar04@cibnor.mx)