PSA Nutrition: Feed Ingredients II

Nine thousand eight hundred, day old male Cobb X Cobb broilers were utilized in a 5x2 factorial design (10 replications/treatment) to determine the effects of five B-vitamins (riboflavin, pantothenic acid, niacin, B12 and folic acid) fortification levels (NRC, 2X, 4X, 8X and 16X NRC) and two levels of stress (low and moderate) on the performance of 0-49 day broilers. Diets were formulated to be isocaloric and isonitrogenous. The starter diet was fed in crumble form and the grower and finisher diets in pellet form. Across stress levels, broilers at 21 days had body weights of 645, 666, 693, 704 and 715 grams and corrected feed efficiency of 1.438, 1.410, 1.388, 1.376 and 1.371 when supplemented with NRC, 2X, 4X, 8X and 16X NRC B-Vitamins, respectively. Carcass dry yield increased as vitamin supplementation increased (65.5, 66.3, 66.7, 67.5 and 68.5% for NRC, 2X, 4X, 8X and 16X NRC supplementation, respectively) and breast meat as percent of live weight also increased (16.12, 16.36, 16.75, 17.02 and 17.19% for NRC, 2X, 4X, 8X and 16X NRC supplementation, respectively). Fat pad as percent of live weight decreased with increased supplementation (13.08, 12.72, 12.55, 12.31 and 12.17 for NRC, 2X, 4X, 8X and 16X NRC supplementation, respectively). Under moderate stress, broilers fed 4X NRC had a $0.17/bird advantage and 42X return over the NRC treatment birds. Broilers fed 16X NRC levels had a $0.18/bird advantage and 10X (1000%) return over 2X NRC and $0.13/bird advantage and 8X (800%) return over 4X NRC.