Research On Animal Production

In order to investigating the effect of exogenous enzymes on growth performance, blood and rumen parametes,18 Brown Swiss male bulls were used in an balanced completely randomized design. The experimental diets were: 1) basal diet (control), 2) basal diet containing 0.50 g enzymatic mixture /kg DM of diet and 3) basal diet containing 0.75g enzymatic mixture /kg DM of diet. The bulls were fed total mixture ration (35 percent corn silage and 65 percent concentrate). Results showed that the experimental diets had no significant effect on dry matter intake, average daily gain and feed conversion ratio (P>0.05), but significant differences were observed in dry matter digestibility of diets (P<0.05), as highest and lowest of dry matter digestibility were related to diet containing 0.50 g enzymatic mixture/kg DM and 0.75 g enzymatic mixture/kg DM, respectively. Rumen liquid pH of the calves was significantly affected by the experimental diets (P<0.05). Calves fed with diet containing 0.50g enzymatic mixture /kg DM had the highest rumen liquid pH. Rumen liquid NH3-N wasn’t significantly affected by the experimental diets (P>0.05). The experimental diets containing enzymatic supplement had significantly affect on blood metabolites (glucose, blood urea nitrogen, triglyceride and aspartate transaminase) except for alanine transaminase and rumen liquid NH3-N. Therefore, using of enzymatic supplement did not has positive effects on growing performance in brown Swiss fattening bulls, but enzymatic supplement increased some of serum blood and rumen parameters.