Effects of different sources fat on performance immune system and intestinal microflora in commercial laying hens

This study was conducted to investigate the effects of different fat sources on production performance, immune system and intestinal microflora in commercial laying hens. In this study 140 laying hens in 7 groups, with 5 replications for 12 weeks were used studied. Production performance, humoral immunity and intestinal microflora population were investigated. The results showed that different levels of fat sources increased significantly egg production and egg mass but decreased feed conversion ratio(p < 0.05). Different levels of fat sources were able to significantly increase immune responses in laying hens. Antibody titers in response to SRBC at 28 days were higher in soybean oil and kilka oil groups than in soybean oil and control groups (p < 0.05). The result also showed that adding different sources of fat to the diet reduce population salmonella, E. coli and Coliform compared to the control group (p < 0.05). Overall, it can be stated that different fat sources, especially fish oil, can improve the immune responses, performance and microbial population of the intestine in laying hens.