1Department of Physiology, School of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran
2Department of Aquaculture, School of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran
Supplementary feed exogenous enzymes have improved the growth rates of various food animals. In this research, the effect of Endofeed W, a multienzyme feed supplement, was investigated on the growth of carp. Accordingly, 134 fish (33.1 ± 0.8 g) were randomly allocated to 4 experimental groups. During the first stage of the experiment (10 days), groups 1-3 received 1, 2 and 3 g Endofeed W per kg diet, respectively. The fourth group (control) received a placebo. All fish were weighed and redistributed for the second stage of the experiment, during which the test groups received 0.25, 0.5 and 1 g Endofeed W per kg diet, respectively. During the first stage of the experiment, the multienzyme supplement reduced the fish weights, dose dependently, being statistically significant with the highest dose (P<0.05). During the second stage of the experiment, a rather similar weight loss, especially with higher doses of the supplement, was observed. However, the differences were not significant (P>0.05). The feed conversion rates were evidently higher in groups receiving Endofeed W. The present study suggests the enzyme supplement, Endofeed W, is not only ineffective in improving the growth and feed conversion rates of carp, it may even exert negative effects with higher doses.