عنوان مقاله [English]
نویسندگان [English]چکیده [English]
The effects of probiotics and antibiotics and fat type in diet on broiler performance were studied by using 900 one-day old Ross 308 chicks in a three × three factorial arrangement with three types of fat (nonfat, three percent fatty acid and three percent soy oil) and three growth promoters (without GP, flavomycin and protexin) in completely randomized design with four replicates per each treatment. Fat and its type had significant effects on weight gain and the body weight gain of birds fed diets containing soy oil were better (P< 0.05). Dietary flavomycin supplementation improved weight gain and FCR (P< 0.05). The fat type × growth promoter’s interaction influenced broiler performance, significantly (P< 0.05). Birds fed on diets containing soy oil and flavomycin showed the highest feed intake and weight gain, whereas, the lowest feed intake and weight gain was belonged to birds fed diets containing fat and protexin (P< 0.05). From the results obtained, it can be indicated that addition of protexin to diets containing fat has negative effect on broiler growth performance.