The effect of prebiotic additive feeds on growth performance andgut histology in brown trouts (Salmo trutta macrostigma Dumeril, 1858)

Brown trout is a type of trout that has a high economic value and a very important potential in aquaculture. It is in danger of extinction in its natural environment for various reasons. For this reason, both stockpiling studies in natural environments have been carried out and the breeding potential has been researched. As functional feed additives, prebiotics have been reported to have many beneficial effects on growth, survival, immune system, increased absorption in the intestines and improving the general well-being of some fish and crustaceans. Grobiotic®-A, a commercial prebiotic, has not been evaluated in Salmo trutta macrostigma to date as a feed additive. This is a preliminary study of Grobiotic®-A prebiotic supplementation to brown trout feed. In this study, the effects of Grobiotic®-A on the growth performance, intestinal structure and body composition of brown trout were investigated. For this purpose, 600 fish with an average weight of 0.43 g were used. Grobiotic®-A was applied to fish with artemia and bait. After 90 days of feeding the experimental diets, no effects on weight gain, specific growth rate, survival rate and body structure were observed between the control and Grobiotic®-A added groups. However, the intestinal villus length of fish fed 1.4% Grobiotic®-A was significantly higher in control and feed with 2.8% Grobiotic®-A. In addition, more oil formation was observed in both Grobiotic®-A reinforced groups compared to the control group.