Performance comparison of laying hens segregating for the frizzle gene under thermoneutral and high ambient temperatures

摘要: ABSTRACT The effect on thermotolerance of the incompletely dominant frizzle (F) gene, which causes feather curling and mass reduction, was investigated in 281 laying hens that were homozygous for mutation (FF), heterozygous (FN), or normally feathered (NN). One-half birds kept under standard conditions (22°C) half exposed to high ambient temperatures (32°C) between 24 46 wk age. Egg production, egg quality, feed efficiency, dissection traits recorded compared. At conditions, production quality did not differ among 3 genotypes, whereas efficiency lower birds. Under heat stress superiority theFF evident all quantity traits. No significant difference measured carriers hens, indicating incomplete behaved as a recessive regarding tolerance. From this study, we deduced theF its state has beneficial decreasing poultry it could be particularly advantageous tropical countries where average are never too low negatively affect efficiency.