The Effect of Frequency of Ejaculation on the Semen Production, Seminal Characteristics, and Libido of Bulls during the First Post-Puberal Year

Abstract

In a study using 9 Holstein bulls, sexual interest was first expressed at an average age of 29.4 weeks. Ability to ejaculate was first shown at an average of 38.9 weeks. Highly significant differences were found in semen volume, percent motile sperm, sperm concentration, total sperm / ejaculation and total motile sperm / ejaculation as the bulls aged during a 1-year period after puberty. No significant differences in semen volume, sperm concentration, percent motile sperm, semen pH, total sperm per ejaculation, total motile sperm per ejaculation, or percent atypical sperm were found attributable to frequency of ejaculation when frequencies of 1, 2 and 3 times/week were compared. A highly significant reduction of libido, was found in bulls scheduled to ejaculate 3 times/week.