Selection for increased semen yield in the turkey

Selection was effective in greatly increasing semen yield in the turkey. After five generations of selection semen yield in the selected line was more than double that of the randombred control line from which the semen line was developed. The realized heritability of semen yield was .35 +/- .20. There was no consistent change in sperm concentration or frequency of bent sperm associated with the increased yield. Egg production was increased in the semen line. The increase occurred in the first generation of selection and was maintained throughout the remaining generations of selection. Body weight during the growing period exhibited an initial increase in the semen line but declined to randombred control levels in later generations. There was no consistent change in percent fertility, percent hatchability of fertile eggs or number of poults produced per hen which was associated with the genetic increases in semen yield.