Effects of feed restriction on production performance of replacement pullets.
Two experiments were conducted to evaluate the effects of feed restriction on production performance of egg production pullets. In Experiment 1, two brown-egg strains (A and B) were subjected to full feeding, a restricted duration of feeding program, and a quantitative feed restriction program. Two White Leghorn strains (C and D) were subjected to full feeding and restricted duration of feeding only. For Experiment 2, only strains B and D were used and an additional restricted duration of feeding program was studied. Pullets were maintained on these programs to 20 weeks of age. Production data were collected to 66 and 62 weeks of age for Experiments 1 and 2, respectively. Restricted duration of feeding was found to depress body weight by 2 to 3%, and quantitative feed restriction depressed body weight by 5% with feed intake depressed by the same magnitudes. Feed restriction at these levels had no significant effects on hen-day or hen-housed egg production, egg weight, egg mass, or egg grades. Net egg income over feed cost was significantly improved by feed restriction in Experiment 2. Pullets on quantitative restriction produced the greatest returns. This was due to increased numbers of large eggs and the decrease in rearing feed consumption. Feed restriction had no effect on mortality or sexual maturity. Feed consumption, body weight, egg weight, and economic returns were higher for the heavy strain of pullets. Mortality was highest within the light strains.
D000818:Animals; D001835:Body Weight; D002645:Chickens / Q000502:physiology*; D004435:Eating; D005260:Female; D010058:Oviposition