1991 Volume 57 Issue 6 Pages 1153-1157
Attempts were made to elucidate the sublethal responses of common carp Cyprinus carpio exposed to the feed additive butylated hydroxytoluene (BHT). The common carp was admini-stered BHT at sublethal levels such as 0.2-1.6% in the diet for 14 weeks. The growth rate was not found to significantly decrease when common carp were fed a diet with supplements of BHT (p>0.05). However, the declining growth rate was observed to be most significant in the fish fed diet with supplement of 1.6% BHT from the 4th to 8th weeks (p<0.05). The symptoms of hepatopancreas enlargement were commonly found in the fish group fed diet with supplement of BHT. However, this symptom would be alleviated when the fish were switched to the BHT-free dietThe pathological symptoms in hepatopancreas induced by BHT were observed under microscope. The lesions indicated that the enlarged hepatopancreas had heavy steatosis, eosinophilia, and megalocytic hepatosis.