| Popis: |
Two experiments were conducted using Leghorn-type pullets to study the effects of severe feed restriction after 21 weeks of age upon subsequent performance. All pullets were grown from one day to six weeks of age on a 21.6% protein starter diet and from seven to 21 weeks of age on a 14% protein grower diet. At 21 weeks of age, the following four treatments were applied: 1) No feed 1 week; 9% protein grower 4 or 5 weeks; 16% protein layer thereafter. 2) No feed 1 week; 16% protein layer thereafter. 3) Alternate weeks of no feed and 9% protein grower until pullets were 26 or 27 weeks of age then 16% protein layer thereafter. 4) Controls—16% protein layer at 21 weeks of age and thereafter. Sexual maturity, as measured by days of age at 50% egg production was delayed 6.5, 14.5 and 33.5 days with treatments 2, 1 and 3, respectively, when compared to control treatment 4. Withholding feed for one week resulted in an average weight loss of 267 grams (19.2%). Mature body weight was not affected by treatment. There were no significant differences noted in laying hen mortality due to treatment. After the second month of production, no significant differences were found in hen-day egg production through the end of the laying period. |
