Dried probiotics enhances immunity and liver function of final production laying hens maintained at upper temperatures zone

Abstract

Dried probiotics (DP) are feed additives, capable of increasing body resistance and maintaining the balance of the microbial ecosystem in the digestive tract against pathogenic bacteria. Biological age and environmental temperature are important factors determining immunity and liver function. This investigation was performed to evaluate the effect of dry probiotics on immunity (lymphocytes, neutrophils and their balance) and liver function of layer-phase laying hens. This study used 40 layer-phase hens aged 70 weeks with the Completely Randomized Design (CRD) method. It was divided into 4 treatments and 5 replicates., each treatment was without dry probiotics in the diet, 2% dry probiotics in the diet, 3% dry probiotics in the diet, and 4% dry probiotics in the diet. Blood sampling was done every month during the three-month experimental period. The results showed that feeding 4% dry probiotics in the diet had a significant effect (P<0.05) on the levels of lymphocytes, neutrophils and transferase enzyme profile. The immunity and liver function of laying hens appeared to be optimized by feeding 4% dry probiotics in the ration.