title: Effects of modified conventional and reverse-protein rearing dietary regimens on the performance of Leghorn hens.
abstract: Two commercial Leghorn genotypes were used to study the effects of rearing dietary treatments on juvenile mortality, growth, and adult performance. One control, two modified conventional, and three reverse-protein juvenile dietary regimens were compared. The two genotypes differed in egg production, age at 50% egg production, egg weight, egg specific gravity. Haugh units, and monetary returns. There was no evidence of any genotype X dietary treatment interaction. Juvenile dietary treatments had a significant (P less than .05) effect on body weights at 21 days of age that continued through the juvenile and adult periods to 490 days. Age at 50% egg production, feed efficiency, and initial egg weights were also affected. Although hens reared on one of the modified conventional and two of the reverse-protein regimens returned $.53 per bird more than the remaining three rearing dietary regimens, this difference was not significant (P greater than .05). Evidence is provided that reverse-protein juvenile dietary regimens may support adult performance that equal or surpass the performance of birds reared on conventional dietary programs.
mesh_terms: D000818:Animals; D001835:Body Weight / Q000187:drug effects*; D002645:Chickens / Q000254:growth & development*; D004044:Dietary Proteins / Q000494:pharmacology*; D005260:Female; D005838:Genotype; D010058:Oviposition / Q000187:drug effects*
chemical_list: D004044:Dietary Proteins