The experiment was conducted to determine the effects of different fat sources on broiler performance. 192 broiler chicks were used in this experiment with four different dietary treatments and four replications for each treatment and 12 chicks per cage. Chicks were fed for 5 weeks (end of first week of the end of sixth week), with the same energy and protein diets, for the starter period (7 to 21 days) and growth (22 to 42 days). The diets were included: Control diet; a diet containing 5% tallow; Diet containing 5% soybean oil; Tallow and soybean oil diets containing an equal mixture. All diets were in powder form and chickens were fed freely during the period. Food intake and weight were measured at the end of each period. Data were analyzed using statistical software SAS. The results showed higher weight gain of chickens, in the initial period, the period of growth and fat in diets for the whole period, compared to the control diet, (P<0.01). And chicks that were fed with a mixture containing tallow and soybean oil, during the period of the total growth, received the highest weight gain (p<0.01). Diets had no effect on feed consumption in starter period (P> 0.05), but during the whole period of growth, chicks were consumed fed diets, containing a mixture of tallow and soybean oil and soybean oil diet had higher feed intake (p<0.01) compared to the control diet. In the initial period of mixed diets containing tallow and soybean oil and soybean oil diet, improved feed conversion compared to the control diet (p<0.01) and during the growth and all of the period, all diets containing fat had better feed conversion (p<0.01) than the control diet, And mixed diets containing tallow and soybean oil alone to both of them, was improved the feed conversion (p<0.01).
