M Dorrani - Department of Animal Science, School of Agriculture, Shiraz University, Shiraz, I. R. Iran
M.R Rezvani - Department of Animal Science, School of Agriculture, Shiraz University, Shiraz, I. R. Iran

This research aimed to compare the effect of two sources of fat and three levels of a pellet binder on pellet quality, growth performance, prececal nutrient digestibility, carcass, and economic traits in Ross ۳۰۸ broilers. Two hundred and forty-day-old broiler chickens were applied in a ۲ × ۳ factorial arrangement in a completely randomized design with four replicates and ten birds in each replicate. The dietary treatments were two fat sources (soybean oil and fat powder) and three levels of a commercial binder named Glomatin® (۰, ۲, and, ۴% in grower and ۰, ۳, and ۶% in finisher diets). The data were subjected to the procedure of General Linear Models (GLM) of SAS, version ۹.۴ (P ≤ ۰.۰۵). Birds fed the soybean oil-containing diet with the second level of Glomatin® binder (۲% in grower and ۳% in finisher diets respectively) showed the best feed conversion ratio (FCR) in the whole period, and the highest prececal dry matter digestibility, ether extract digestibility, and economic profit. It concluded that increasing the physical quality of the pellet diet by adding a binder in soybean oil-containing diets had an optimum level (۲% in grower and ۳% in finisher diets respectively). Over that optimum level, it could harm FCR, prececal nutrient digestibility, and finally, profitability.

broilers, Fat and oil, Glomatin pellet binder, Physical quality, Prececal digestibility