Abstract
OBJECTIVE: The current research aimed at investigating growth performances and meat yield characteristics of commercial cockerels supplemented with antibiotics and probiotics to the diet. MATERIALS AND METHODS: A total of 1,350 commercial cockerels (ISA Brown) were indiscriminately distributed to 3 treatment groups, each having three replications of 150-day-old chicks based on completely randomized design. The basal diet was treated as the control, while the experimental groups receiving Enrofloxacin 1 gm/kg and Protexin 1 gm/kg feed were considered as antibiotic and probiotic groups, respectively. Bodyweight, feed intake (FI), feed conversion ratio (FCR), and other relevant characteristics were recorded weekly until 49 days of trial. In the end, similar number (10) of birds from each replicate group were slaughtered to determine the carcass characteristics. RESULTS: Significantly, better results were found in the overall growth performances of the cockerels in the probiotic-fed treatment group. Highly significant differences were also found in live bodyweight, weight gain, daily gain, FI, FCR, survivability, dressing percentage, abdominal fat, breast meat, drumstick, and thigh weight in the probiotic-fed treatment group compared to the others. CONCLUSION: The results of the present study indicate that the inclusion of dietary probiotics has a superior performance to antibiotics and may have the potentiality to be used as an alternative growth enhancer in the diet of cockerels.