Dietary poultry fat and gastrointestinal transit time of feed and fat utilization in broiler chickens

An experiment was conducted with broiler chicks to determine the effect of 0, 5, 10, and 20% supplemental poultry fat and age on gastrointestinal transit time (GTT) and the effect of supplemental fat on fat utilization and growth. Mean GTT, measured with chromic oxide or ferric oxide, was not affected by supplemental fat. There was a curvilinear relationship (rising ogive) between mean GTT and age. It increased from an estimated lower plateau of 170 min to an upper plateau of 211 min with the inflexion point at 3.23 wk. At 6 wk of age, birds receiving supplemental fat consumed more energy and were heavier and more efficient. Total lipid digestibility increased with supplemental poultry fat but digestibility of poultry fat was not altered. The AME of poultry fat ranged from 8.1 to 8.4 kcal/g at 5 to 20% inclusion in the diet.