Comparison between the effects of two multi-strain probiotics and antibiotic on growth performance, carcass characteristics, gastrointestinal microbial population and serum biochemical values of broiler chickens

This experiment was conducted to evaluate the effect of two types of probiotic and antibiotic virginiamycin on performance, carcass characteristics, gastrointestinal microbial population and Serum biochemical values of broiler chickens. Based on a completely randomized design, three hundred day old Ross 308 broilers were allotted into 4 treatments with 5 replicate pens per treatment and 15 broilers in each pen for 42 days. Dietary treatments were (1) an antibiotic-free corn-soybean meal mash basal diet (control), (2) control + 200 g/ton of virginiamycin, (3) control + 1500 g/ton of fermented probiotic produced and isolated from fermented poultry slaughterhouse wast, and (4) control + 1000 g/ton of commercial probiotic (BioPlus-2B®). The results indicated that the use of antibiotic improved body weight gain (BWG) (7.2 and 8.6 % respectively) and feed conversion ratio (FCR) (3.24 %) as compared to control and commercial probiotic treatments (P<0.05). Also, the birds under virginiamycin treatment had higher feed intake (FI) than those treated with commercial probiotic. The use of fermented probiotic