Turkey Semen Evaluation for Fertility Prediction

A preseasonal method for determining the reproductive potential of turkey toms would be advantageous to breeders in selecting breeder males. This study was designed to evaluate semen volume, sperm concentration, and percent progressive motility of spermatozoa in relation to the predictability of potential fertilizing capacity. Number of progressively motile sperm per ejaculate (N.P.M.S.E.) was computed and denned for analysis as a single parameter of semen quality. Ejaculates were also tested for fertilizing capacity on four hens for each male. Twenty males were selected from a population of 54 and ranked prior to the experimental period on the basis of number of motile sperm. Each torn was used to inseminate the same hens for six biweekly periods. Fertility was determined for two weeks of production following each insemination. There were significant differences in fertility, semen volume, sperm concentration, motility, and N.P.M.S.E. among toms. Significant correlations between fertility and N.P.M.S.E. were determined prior to and during the experimental period. Significant correlation between sperm concentration and percent fertility was determined in only one out of five trials. N.P.M.S.E. accounted for 6 percent of the variation in fertility prior to the experiment and 18.5 percent during the experiment. Eighty percent of those toms characterized as high producers of N.P.M.S.E. at the beginning of the experimental period continued to produce at high levels. It was concluded that N.P.M.S.E. could be used to identify potential low fertility males for removal from the breeding flock as well as to indicate males with high fertilizing potential.