Effect of Exhaustive Ejaculation on Composition of Bovine Semen

To obtain information on the nature of sperm and of the glandular fluids produced through exhaustive ejaculation, normal, infertile, or bilaterally vasoligated bulls of various breeds were subjected to exhaustive semen collection by artificial vagina (AV) service, electroejaculation, or a combination of these. Electric stimulation was applied at approximately 3-rain intervals. Collections were n-rode during periods of tess than 3 hr, and quantities of seminal fluid between 85 and 225 ml were obtained. Fructose, nitrogen, and sperm concentration in the ejaculates were correlated, whereas pH was inversely related to these components. Free amino acid and protein patterns were normal in intact and infertile bulls during early ejaculates, but became distinctly abnormal as exhaustion was approached. In an infertile bull, abnormal sperm of the secondary type decreased as primary abnormalities increased. The percentage of sperm showing no affinity for nigrosin-eosin vital stain (presumably live sperm) increased during exhaustive ejaculation.