Abstract: Probiotics are claimed to have beneficial effects on health. The production parameters, including were monitored weekly during a 6-wk trial. Body weight was affected by dietary treatments in 21, 28 and 42 days of age (p< 0.05). The BW in the 0.1% DFM treatment was significantly (p< 0.05) higher than 0.15% DFM and control in 28 and 42 days. Body weight gain in probiotic treatments was significantly more than control treatment (p< 0.05). Moreover, body weight gains in 0.1% DFM were higher than 0.15% DFM treatment (p< 0.05). Feed intake in control treatment was significantly higher than (p>0.05) 0.1 or 0.15% DFM treatments. Feed conversion ratio in 0.1 and 0.15% DFM treatments was significantly (p< 0.05) better than control treatment. The 0.1% DFM and control treatments have lowest and highest FCR, respectively. The antibody titer against IBDV in 0.1 and 0.15% DFM treatments were significantly (p< 0.01) more than control treatment but no significant difference among 0.1 and 0.15% treatments. It is concluded that dietary supplementation of DFM probiotic improved body weight, body weight gain and feed conversation ratio and enhanced humoral immune response.
Mehdi Nayebpor , Parviz Farhomand and Ali Hashemi , 2007. Effects of Different Levels of Direct Fed Microbial (Primalac) on Growth Performance and Humoral Immune Response in Broiler Chickens . Journal of Animal and Veterinary Advances, 6: 1308-1313.