Seasonal variations in semen traits of exotic cattle bulls of different age groups in the subtropical region

Abstract

Background: The age of the bull and season of semen collection may significantly impact semen characteristics, although the results of previously published studies vary somewhat. Unfortunately, breeding programs still do not account for male reproductive traits for a bull's fertility. The effects of season and age on the quality of exotic cattle breeds’ semen have been investigated in the current study. Methods: Two exotic cattle breeds, Jersey and Holstein Friesian, have been chosen from the subtropical region of India for study. The pooled dataset from the Information Network for Animal Productivity & Health (INAPH, 2017–2022) containing data collected at the Frozen Semen Bank in Bassi, Jaipur, India, on three semen traits was used in the study. Three semen traits of exotic bulls – total semen volume, sperm concentration, and the number of sperms per ejaculation were examined in connection to the influences of age and season. Results: The age of the bulls was found to influence the concentration and sperm counts significantly. The semen volume was minimal in the older group, while the sperm concentration was lowest in the adult group. All the tested semen traits were highest in summer and lowest in winter. Conclusion: Therefore, it was concluded that the age and seasonal variations significantly influence the semen quality of exotic cattle breeds and suggested that the reproductive traits of the bulls should be considered for the breeding programs.