The response of broilers grown to 49 days under humid tropical conditions, when feeding durations of starter, grower, and finisher diets are varied. (112)

Abstract

A study was conducted to evaluate the response of broilers to changes in the duration of feeding starter, grower, and finisher diets when grown to 49 days in hot weather conditions. A total of 2560 day-old commercial broiler chicks of mixed sex (straight run) were assigned to 32 pens and 16 treatments were randomly assigned resulting in a completely randomized design. Diets were formulated to meet nutrient levels typical of the current local industry. Diets were changed from starter (222 g CP kg-1, 12.77 MJ ME kg-1) at 10, 15, 20, 25, or 28 days 1 to grower (202 g CP kg-1, 12.76 MJ ME kg-1) and from grower to finisher (198 g CP kg-1, 12.77 MJ ME kg-1) at 36, 41, 43, or 46 days of age or not at all. Broilers grown to 49 days attained the desired weight of 2400 g on all feeding programmes evaluated. Feed consumption responses over time were quadratic for the durations of feeding starter diet (R2 = 0.99), grower diet (R2 = 0.88), and finisher diet (R2 = 0.99). Similarly, responses of live body weight gain were quadratic for the durations of feeding starter diet (R2 = 0.99), grower diet (R2 = 0.96), and finisher diet (R2 = 0.99). It was concluded that the starter diet feeding duration could be reduced from the current practice of 28 days in hot climates to between 15 and 21 days without any effect on final body weight, carcass yield, leg quarter, and breast yield.