Location: Food and Feed Safety ResearchTitle: Effects of dietary supplementation of a commercial prebiotic on survival, growth, immune responses, and gut microbiota of the Pacific white shrimp, Litopenaeus vannamei) Author
|Gatlin iii, Delbert|
Submitted to: Aquaculture Research
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/13/2013
Publication Date: N/A
Citation: Interpretive Summary: A feeding study was conducted to evaluate growth, bacterial populations of the intestine, and immune system responses of shrimp fed diets containing a commercial prebiotic. At the end of the study, differences in weight gain and survival among study groups were not significant. However, the use of a molecular technique, denaturing gradient gel electrophoresis, revealed that the bacterial communities in the intestine changed significantly as affected by the presence of the prebiotic in the feed. Therefore, the prebiotic was able to modify the bacterial communities in the intestine. In addition, shrimp fed the prebiotic had a greater immune system response than shrimp not fed the prebiotic. Although in the present experiment shrimp were not exposed to virulent pathogens, the positive immune system response in shrimp fed the prebiotic suggests that an improved response to a real pathogen infection would be anticipated in the prebiotic-fed shrimp. This study is of importance and interest to shrimp aquaculture researchers and producers.
Technical Abstract: A 35-day feeding trial was conducted to evaluate growth, bacterial populations of the gastrointestinal tract (GIT), and immune responses of Litopenaeus vannamei fed diets containing the commercial prebiotic PrevidaTM. Four diets were formulated to contain Previda at 0, 0.2, 0.5, 1.0, or 1.6% by weight. At the end of the study, differences in weight gain and survival among treatments were not significant (P > 0.05). However, denaturing gradient gel electrophoresis analysis revealed that the microbial communities in the GIT changed significantly as affected by the presence of dietary Previda. Therefore, the prebiotic was able to selectively modify the microbial communities in the GIT. Although individual bacterial species were not identified, enteric populations in shrimp fed the prebiotic were genetically similar. In addition, shrimp fed Previda at 1.6% responded significantly (P < 0.05) better immunologically as hemocyte phagocytic capacity, hemolymph protein, hyaline cell counts, and hemolymph glucose greatly improved compared with the same responses of shrimp fed the basal diet. Although in the present experiment shrimp were not exposed to virulent pathogens, the observed up-regulation of some of immune responses upon prebiotic supplementation indicate that an improved outcome of such challenges may be anticipated in Previda-fed shrimp.