Feeding broiler breeder males. 1. Effect of feeding program and dietary crude protein during rearing on body weight and fertility of broiler breeder males.
A 2 x 2 factorial experiment was conducted to compare the effects of 2 male broiler breeder feed allocation programs (Concave or Sigmoid) during the rearing period to 26 wk of age and the interaction with dietary CP (12 or 17%) on BW and fertility. From 0 to 2 wk, all birds received a starter diet, after which, pens were randomly assigned to the 4 treatment combinations that ended at 26 wk of age. All males were weighed individually at 4, 8, 12, 16, 22, 26, 28, 32, 36, 40, 48, 52, 56, and 64 wk of age, and fertility was determined weekly from 27 to 32 wk of age and then every 2 wk to 64 wk of age. At 49 wk of age, the male feed allocation for all treatments was increased by 5 g/d. Even when fed the same as Sigmoid program males during the production period, males reared on the Concave feeding program lost BW from 32 to 40 wk of age and exhibited lower BW from 40 to 48 wk of age, which corresponded to a more rapid decrease in fertility. The 17% CP diet increased BW from 8 to 32 wk of age, but no significant differences were subsequently observed. The 12% CP rearing diet improved both weekly and cumulative fertility. A significant interaction between rearing feeding program and dietary CP during the third quartile period showed that the Concave program-17% CP diet combination was most negatively affected. The increase in male feed allocation at 49 wk restored fertility and caused differences among treatments to diminish. These data suggested that BW during the early rearing period did not affect fertility, but an increased BW due to either providing fast feed increments toward the end of the rearing period (Concave) or feeding a 17% CP diet produced males that were unable to sustain fertility after 40 wk of age without an appropriate allocation of feed.
Romero-Sanchez
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Faculty of Agriculture, Grupo Grica, University of Antioquia, AA 1226 Medellin, Colombia.
Plumstead
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PW
Brake
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J
D000821:Animal Feed / Q000032:analysis; D000822:Animal Husbandry / Q000379:methods*; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001835:Body Weight / Q000187:drug effects*; D002645:Chickens / Q000254:growth & development*; D004032:Diet / Q000662:veterinary; D004044:Dietary Proteins / Q000494:pharmacology*; D005298:Fertility / Q000187:drug effects*; D008297:Male; D013997:Time Factors
D004044:Dietary Proteins