Grower Diets and Their Effects Upon Subsequent Performance of Layer Type Pullets

Five life-cycle experiments were conducted over as many years involving nearly 10,000 pullets of layer-type. Grower diets of 12% protein and 2550, 2900, 2970, 3180, or 3190 kcal of ME/kg were compared with 10% protein-1970 and 16% protein-3090 kcal type diets. Corn, oats, dehulled oats, and oat hulls were used to vary the energy levels. In the first experiment, feed requirements for growth were greater with the 10-1970 diet as compared to that for a 12-2900 diet, but no residual differences during the lay period were noted for egg production or feed conversion. Livability was slightly higher for birds grown on the 10-1970 diet A second experiment confirmed these results. A mixture of neomycin and terramycin to supply 22 ppm each to the grower diets in the first experiment had no consistent effect on subsequent performance. A third experiment showed that supplements of lysine and methionine to the 12-2900 diet to provide National Research Council (NRC, 1971) requirement levels were not needed for immediate growth and feed conversion or for subsequent reproductive performance. In this study, a diet using dehulled oats (12-3180) improved feed conversion during growth but had no subsequent effects on reproductive performance. A fourth experiment utilized 12% protein diets with oats (2550), corn (3190), or corn and oats (2970) as the cereal components. These grower diets were compared with a 16-3090 corn diet Growth and feed conversion were reduced by the all-oats diet; feed conversion was greatest with either all-corn diet. During the lay period, the only significant effect was reduced egg production from pullets grown on the 12% protein-corn diet (12-3190). A fifth experiment involved the 12-2970 (corn and oats) versus 12-3190 (corn) grower diets. No significant differences were noted in reproductive performance due to grower diet.