Effect of body weight, feed allowance, and dietary protein intake during the prebreeder period on early reproductive performance of broiler breeder hens.
In Experiment 1, two groups (n = 180) of breeder pullets were selected at 16 wk from two larger groups with BW of either 1,591 +/- 43 (LBW) or 1,988 +/- 59 g (HBW). From 16 wk of age until a peak feed allotment of 159 g per bird per day, weekly feed allowances were increased in a low (LOW), medium (MED), or high (HIGH) manner. There were significant differences (P less than .05) in BW between the LBW and HBW treatments through 32 wk of age. Within each pullet weight class, the HIGH treatment was numerically heaviest through 32 wk. The HBW hens had significantly improved hen-day production from 24 to 28 (P less than .001) and 28 to 32 wk (P less than .06). The LOW treatment resulted in significantly poorer production in both the LBW and HBW weight groups from 24 to 28 wk. There were no signficant treatment effects on egg weight at a given age. Within each pullet treatment, the HIGH treatment resulted in an increased percentage of double yolked (DY) eggs from 24 to 28 wk (P less than .05) and 28 to 32 wk (P less than .07). In experiment 2, pullets in each of two pullet treatments received approximately 12 kg of feed from 2 to 24 wk of age. One treatment received a greater quantity of feed early in the rearing period (HEAVY) while pullets in the other treatment received a greater quantity of feed later in the rearing period (LIGHT). One-half of the pullets from each rearing treatment were fed either a 14% (LOWPRO) or 18% (HIGHPRO) protein diet during the prelay period (18 to 24 wk). Pullets in the HEAVY treatment were significantly heavier (P less than .01) than those in the LIGHT treatment at 21 but not at 24 wk. The HIGHPRO treatment resulted in a significant improvement (P less than .05) in hen-day egg production from 24 to 28 and 28 to 32 wk. There were no treatment effects on egg weight, and the LOWPRO treatment resulted in a significant increase (P less than or equal to .01) in the number of DY eggs from 28 to 32 wk.
Lilburn
M S
MS
Poultry Science Department, Ohio State University, Wooster 44691.
Myers-Miller
D J
DJ
D000818:Animals; D002645:Chickens / Q000254:growth & development / Q000502:physiology*; D004044:Dietary Proteins / Q000378:metabolism*; D004435:Eating / Q000502:physiology*; D005260:Female; D010058:Oviposition; D011897:Random Allocation; D015430:Weight Gain / Q000502:physiology*
D004044:Dietary Proteins