Beltsville Poultry Semen Extender. 8. Factors affecting turkey semen held six hours at 15 C.

Several experiments were conducted to measure the effects of extender pH, size and type of storage vessel, insemination dose volume, and frequency of insemination on the motility and fertilizing capacity of turkey semen held 6 hr at 15 C. The fertilizing capacity and motility of both unstored and stored turkey sperm were depressed more when diluted in Beltsville Poultry Semen Extender at pH 5.5 than at pH 6.5 or 6.0. The fertility of stored semen was impaired when agitated for 6 hr regardless of the type of storage vessel used. Sperm motility was higher when semen was held in flasks than when held in tubes. There were no differences in fertility of hens inseminated with .025, .05, or .10 cm3 of either unstored or stored semen during the first 10 weeks of egg production. However, fertility differences between unstored and stored semen were noted with all insemination doses late in the production period. Hens inseminated every 7 days with unstored semen maintained a constant level of fertility (+90%) for the 20-week production period, whereas the fertility of hens inseminated at 10- or 14-day intervals was lower in Weeks 11 to 20. Regardless of insemination interval, fertility of stored semen was lower than fertility of unstored semen in the latter stages of egg production.