The effects of fish meal replacement by yeast based nucleotides on growth body composition and digestive enzyme activity in rainbow trout juveniles Oncorhynchus mykiss

HUNT, ARZU ÖZLÜER | YILMAZ, FERBAL ÖZKAN | ENGİN, KENAN | YALIN, SERAP | ŞAHİN, NEFİSE ÖZLEN

This 60 day study investigated the effects of organically certified nucleotide yeast-derived protein source (Nu-Pro®) on growth, feed efficiency, fillet proximate composition and digestive enzymes in rainbow trout (Onchorhyncus mykiss). Diets were isonitrogenous and isocaloric. Three experimental diets wherein 20%, 40% and 60% of the fish meal content was replaced by Nu-Pro®, were compared to the control diet in which the crude protein content was anchovy fish meal and corn gluten meal. The rainbow trout (initial weight 27 g/fish) were fed twice daily in 200-l Aqaria. Live weight gain increase ranged from 125-195% in fish fed the experimental diets. Results indicated that up to 40% fish meal protein can be replaced by Nu-Pro® without compromising growth rates, feed efficiency or the fillet...