Changes in the characteristics of turkey ejaculated semen and ductus deferens semen with repeated ejaculations.

Studies were conducted to assess (a) the pH and motility of semen removed from the ductus (d.) deferens and receptaculum from males sexually rested 1 wk, (b) the pH, motility, and sperm concentration of semen after each successive ejaculation (ejaculated 3 or 5 times at 30-60 min intervals) and (c) the rate of semen replenishment and the fertility of the replenished semen after emptying the d. deferens by repeated ejaculations. In both Large and Small White turkeys, the pH of the semen decreased progressively from the proximal segment of the d. deferens to the receptaculum. Sperm from all segments of the d. deferens were motile. With multiple ejaculations, the pH of successive ejaculates increased. Sperm concentration in the first and second ejaculates were the same, but the concentration in the third ejaculate was reduced. After 5 successive ejaculations 0.08 ml (12 p. 100 of the total volume of the 5 ejaculations) remained in the d. deferens. After the 5 successive ejaculations the semen volume in the d. deferens was replenished between 4 and 5 days and the total sperm number was replenished within 3 days. Before ejaculation the fertility of semen from the proximal and distal d. deferens was equal to the fertility of the first ejaculate. After multiple ejaculations, the fertility of the third ejaculate was slightly less than the fertility of the first ejaculate. The fertility of semen collected from d. deferens 24 hr after multiple ejaculations was lower in the first of 2 fertility trials, but was not reduced in the 2nd trial. However, in both trials the fertility of semen collected from the d. deferens 72 hrs after 5 successive ejaculations, was the same as fertility of the first ejaculate.