The use of low‐protein diets in the 12‐ to 18‐week period of light hybrid pullets

Synopsis

Three diets, containing nearly 12.5 MJ/kg (3.0 kcal ME/g) and 14.6, 11.3 and 9.1 % crude protein, were fed to 1680 light‐hybrids from 12 to 18 weeks of age. Body weight at 18 weeks was depressed by 5 and 9% and age at sexual maturity delayed by 2.4 d and 2.8 d for groups fed the intermediate and lowest protein diets respectively. Mortality during the experiment was slightly higher in the group receiving the higher protein diet. There were no consistent or significant treatment differences in mortality during the laying period. Both hen‐day rate of lay and egg weight decreased slightly and insignificantly but progressively with decreasing protein level of diets fed in the 12‐ to 18‐week period. Savings in food costs in the 12‐ to 18‐week period from feeding the cheaper lower‐protein diets were more than offset by the reductions in egg output and returns which resulted.