The Effects of Different Levels of Saturated and Unsaturated Fats and Their Composition in Growing and Finishing Periods on Productive Performance and Blood Lipids of Broilers

This experiment was conducted to investigate the effects of different levels of saturated and unsaturated fats and their composition in growing and finishing periods on performance, carcass traits and blood lipids level in broiler chickens. In this experiment, 432 Ross 308 broilers were used from 11 up to 42 days in 9 treat-ments, 4 replicates and 12 birds in each replicate in growing (11-24 days) and finishing (25-42 days) peri-ods in a completely randomized design. Treatments included: 1) control group (without fat), 2) 2% canola oil, 3) 4% Canola oil, 4) 2% beef tallow, 5) 4% beef tallow, 6) 2% canola oil + 2% beef tallow, 7) 4% ca-nola oil + 2% beef tallow, 8) 2% canola oil + 4% beef tallow and 9) 4% canola oil + 4% beef tallow. In the growing period, different levels of fat sources had no significant effects on the performance of broilers. In the finishing period, the higher amounts of daily weight gain and final live weight were obtained in group 8 (P<0.05). In the whole feeding period, the best feed conversion ratio and final live weight were observed in group 8 (P<0.05). The lowest amount of intestine, abdominal, gizzard and liver weights belonged to control group (P<0.05). However, a difference was observed between the control group and group 8 in these re-spects. Using different levels of saturated and unsaturated fat in growing and finishing periods had no sig-nificant effect on the blood lipids level of broilers (P>0.05). The overall results indicated that in broilers, using mixing of saturated and unsaturated fats have beneficial effects on their performance.