THE PERFORMANCE OF LAYING HENS REARED ON RESTRICTED AND FULL FEEDING PROGRAMS

Experiments were conducted in 3 successive years to measure the effect on the performance of laying hens of restricting feed during the rearing period on range. About 1100 birds were reared and carried through a laying year in each experiment. Feed restriction was 72, 76 and 63 per cent of full feed for the test groups in Experiments 1, 2, and 3 respectively. All birds were full-fed in the laying house.Feed restriction changed the pattern of egg production, in that the restricted birds came into production later but subsequently laid at a higher rate than their full-fed counterparts. After 318 and 322 days in production the restricted birds in Experiments 1 and 2 respectively had overcome the disadvantage of a late start (7 and 14 days) and produced as many eggs as the full-fed birds. In Experiment 3, the restricted birds were held back 20 days, and after 315 days in production were still significantly behind in number of eggs produced.The restricted birds in the three experiments consumed an average of 0.17 pounds less feed per dozen eggs over the combined rearing and laying periods This amounts to a saving of 3 pounds of feed per bird, since the mean egg production of the restricted groups was 18 dozen eggs per bird.Early egg size was markedly increased by feed restriction and egg weights taken later in the year (after 3 months in production) remained slightly higher for the restricted groups. Albumin score for eggs from the restricted birds was better in all tests, but not significantly so in any given experiment. Specific gravity of the eggs was not influenced by feed restriction.Mortality on range and in the laying house was not affected by feed restriction on range. Body weight at housing time was much lower for the restricted birds but was not significantly lower at the end of the laying year.