THE RESPONSE OF BROILER-CHICKENS AND TURKEY POULTS TO STEAM-PELLETED DIETS SUPPLEMENTED WITH FAT OR CARBOHYDRATES

The responses of growth and feed efficiency to pelleted feed was inves tigated in 4- to 7-wk-old broiler chickens, and in 8- to 12- and 16- t o 20-wk-old turkeys. In all cases, the growth and feed efficiency resp onses were Linear within the ranges of dietary energy tested. When ene rgy was added by carbohydrate supplementation, weight gain and feed ef ficiency responses were parallel for both mash and pellets, but due to the growth response to pellets, the elevation was higher for pellets than for mash. When energy was added by fat, the growth response to pe llets also resulted in an increase in function elevation but the slope of the response was lower than in mash feeding, possibly due to a dec line in pellet quality as dietary fat increased. Grinding of pellets c ompletely abolished the growth and feed efficiency responses observed when the physical form was preserved. In chickens, comparisons of grou nd pellets to mash suggested some decline in nutritional quality due t o the process of pelleting when either carbohydrates or fat were incre ased in the diets. Ln both chickens and turkeys, the feeding of pellet ed diets resulted in an increase in abdominal fat.