Comparison of Quality of Bull Semen Collected in the Artificial Vagina and by Electroejaculation

Abstract

Electroejaculated (EE) semen is at least comparable in quality to semen collected in the artificial vagina (AV). The volume of A semen was less (2.8 vs. 6.3 ml.) and the concentration greater (625 vs. 299 million sperm/ml) than that obtained by EE; however, if sufficient volume of semen is obtained by EE, essentially the same number of total sperm per ejaculate can be obtained by each method. Ninety-four per cent of the EE samples and 68% of the AV samples had an initial motility considered acceptable for artificial insemination. At the end of four days of storage, 55 and 18%, respectively, still had acceptable motility. Samples with a higher pit are usually of inferior quality when compared to other samples collected by the same method, but they are not necessaxily inferior to samples collected by a different method. The mean pit for the EE samples (7.3) was 0.6 of a unit higher than for the AV samples, but the EE samples maintained higher motility during four days of storage than those collected in the AV. Since a higher pit and lower concentration of fructose was obtained in the EE samples, it is postulated that the larger volume of fluid comes from the urethral glands, with a slight increase from the seminal vesicles. Semen was obtained more consistently by the EE technique and it is adaptable to nearly all bulls, with no selection on ability or desire to serve the A.