Sexual maturity in broiler breeder males.

Sexual maturity and fertility of two lines of broiler breeder males, one commercial and one experimental, were evaluated individually in order to determine the earliest age at which they could be expected to produce viable spermatozoa capable of producing acceptable fertility. Comparative data for the two lines were also collected on duration of fertility, percent fertility, percent hatchability and chicks per hen during an 8-week period using pooled semen from each of the two lines. The results of this study indicate that 9.1 and 6.8% of the male of the experimental and commercial lines, respectively, produce viable spermatozoa at 11 weeks of age, and consequently, could be selected at that age and used to reproduce stock under selection. The duration of fertility was 10.5 days for the experimental line and 8.8 days for the commercial lines; with fertility levels of 86.1 and 82.8%, respectively, for the eggs produced by the two lines during this period. There were no differences in fertility, hatchability, or chicks produce per hen between the two lines for the 8-week reproductive period.