Effects of ambient temperature on sexual maturity in chickens

Ninety-six, 14-day-old Single Comb White Leghorns (48 males and 48 females) in each of two trials were divided into three groups and grown thereafter under one of the ambient temperatures of 21, 29, or 35 C. Age at sexual maturity of males was decreased in both trials as temperature was increased. First semen was produced at 54 and and 56 days of age in Trials 1 and 2, respectively, when the ambient temperature was 35 C and 68 and 63 days at 21 C for Trials 1 and 2, respectively. Sexual maturity of females was significantly delayed at the highest ambient temperature. Semen quality was only slightly affected by the highest ambient temperature. Although egg production was seriously affected at 35 C, fertility and hatchability, except in a few instances, were only mildly affected.