An Investigation of the Effects of Using An Enzyme-Probiotic Combination on Broilers Performance

Background: growth promoters are chemical and bio-logical substances that are added to livestock food with the aim to improve the growth of chickens in fattening and the utilization of food, and in this way achieve better production and financial results. objectives: an experiment was conducted to evaluate the effects of enzyme complex, probiotic, and their combination on performance of broilers fed a basal wheat-barley-soybean meal diet from 1 to 47 d of age. methods: a total of 480-day-old male broiler chicks (arbor acres) were randomly assigned to 6 treatments, with 4 replicate cages per treatment and 20 birds per cage. the experiment consisted of a 3×2 factorial arrangement of the treatments, with 3 concentrations of enzyme complex (0, half of the commercial suggested level or commercial suggested level) and 2 concentrations of probiotic (0 and suggested level). results: results showed that the suggested level of enzyme complex could improve body weight and feed conversion ratio (p < 0.05), but addition of probiotic only decreased the feed conversion ratio (p < 0.05). there was no interaction between enzyme complex and probiotic on performance (p > 0.05). probiotic supplementation did not improve the efficacy of enzyme complex at any levels. the examination of length and relative weight of different regions of intestine showed that only enzyme complex could decrease the relative weight of duodenum and length of jejunum; however, there was no interaction between treatments for these parameters. conclusions: this research did not demonstrate any interaction effect between enzyme complex and probiotic on broilers performance fed wheat-barley-soybean meal diet.