Dietary enrichment with crude protein content and feed additives (Bacillus spp. and yeast strains) improves growth performance, survival and circulating hemocytes in juvenile white shrimp, Litopenaeus vannamei

Abstract

In this study the enrichment dietary effect with different crude protein levels (CP) and feed additives on growth, survival, feed conversion ratio (FCR), feed consumption (FC) and total hemocyte count (THC) in juvenile white shrimp Litopenaeus vannamei were evaluated. The study covered two bioassays: in the first one, juveniles were daily fed for 45 days with four experimental diets containing: (1) Control, commercial feed (35\% CP); (2) 29\% CP; (3) 32\% CP; (4) 35\% CP. After the 29\% CP diet was selected, juveniles in bioassay II were daily fed for 45 days with a and (4) 29\% CP + yeast mix at 1x106 CFUg-1 feed. Juvenile shrimp fed with experimental diets gained significantly more weight and increased of juveniles significantly increased with 29\% CP and 29\% CP + yeast mix diets, compared with control group. Complementing the diet with yeast survival and circulating hemocytes, and addition of mixed yeast as feed additive induced better survival and immune response in juvenile shrimp.