The effect of bentonite and yeast cell wall along with cinnamon oil on aflatoxicosis in rainbow trout (Oncorhynchus mykiss): Digestive enzymes, growth indices, nutritional performance and proximate body composition

Abstract

Feed safety is amongst the main factors affecting animal performance and economic viability of an aquaculture enterprise. The present research was to study the protective effects of mycotoxin binding agent along with cinnamon oil on the toxicity of various dietary aflatoxin levels in rainbow trout fingerlings. A three way factorial experiment was carried out for 60 days. Aflatoxin B1 (0, 25 and 50ng/kg), mycotoxin binder (0 and 5%,) and cinnamon oil (0 and 1%) were deliberately included in the diet. Fish were fed three times a day. Dietary Aflatoxin B1 contamination resulted in better PPV (p<0.05), while those fish fed aflatoxin contaminated diet supplemented with mycotoxin binder showed the highest weight gain (p<0.05). Dietary inclusion of cinnamon oil resulted in significantly inferior growth and nutritional indices. Body lipid, energy and ash contents were mainly affected by cinnamon oil to the extent that fish received diet containing the oil had significantly lower lipid and energy content. Meanwhile, feeding oil containing diet resulted in higher ash content (p<0.05). Markedly increased activity of digestive enzymes including alkaline protease, lipase and amylase were observed in fish fed aflatoxin B1 contaminated diet. However, the presence of mycotoxin binding agent rehabilitated lipase activity of aflatoxin received groups. Trout fed diet supplemented with cinnamon oil tended to have lower digestive enzymes activity. In conclusion, aflatoxin B1 resulted in pathologically elevated digestive enzymes activity in trout and mycotoxin binding agent and/or cinnamon oil could correct the enzymes activity of the species.