Abstract
Commercial source, medium-type male poults were either placed in floor pens with food and water within 6 h after hatching or delayed a subsequent 24 h. Starting feed offered in each case was either of a normal (28% crude protein and 2,850 kcal ME/kg) or high (30% and 3,040 kcal) nutrient concentration. During the initial 2 wk, birds that had been fasted gained less weight but had a better feed conversion than those placed early. Poults which received a ration having a high nutrient concentration gained more weight and had a better feed conversion than those offered the normal diet. Mortality at this time was greater with birds subjected to a fast than those placed early. Having access to the higher nutrient concentration ration led to a greater mortaility than if the normal diet was employed. Body weight differences established during the first 2 wk remained throughout the experiment. Feed conversions of rations common to all groups during the subsequent 2- to 6-, 6-to 10- and 10- to 14-wk periods were not influenced by the early treatments after 6 wk of age. Slaughter at 14 wk did not reveal any differences in apparent carcass yield, conformation or finish grade. Degree of fleshing was reduced when poults were subjected to a post-hatch fast and partially improved when the high nutrient starting diet was fed. Effects of fasting and early nutrition on mortality and carcass changes are explained in terms of biochemical events occurring with the neonate.