Uterine Response Towards Semen Deposition Through Artificial Insemination in Mares: Ultrasonography and Cytology

Abstract

The popularity of equestrian sports has been increasing over the past couple of years in Indonesia, along with the demands of high-quality equine breeding. As one of the most widely practiced breeding method in sport horses, artificial insemination is done with the aims of increasing production and improving the genetic quality of horses. After insemination, a transient and physiological inflammatory response of the uterus occurs which serves to eliminate seminal plasma, excess sperm, debris, and microorganisms from the uterine lumen. This study aims to determine the effects of semen deposition in the uterus post- insemination and mechanism of the post-insemination uterine response in mares through ultrasonography imaging and cytology smear observation. This research was done on 2 Sumbawa pony mares. Ultrasonography imaging and cytology smears were taken before insemination, post insemination, and everyday post insemination until the uterine inflammatory response subsides. Both mares show positive uterine inflammatory response. In Mare A the response started 48 hours post insemination and resolved within 72 hours, and in Mare B, the response started 72 hours post insemination and resolved within 48 hours. Vaginal cytology sample in Mare A, shows the number of neutrophils counted peaked at day 2 with 4 cells per 10 field of view and completely resolved and disappeared on day 5. While in Mare B, the neutrophil count peaked at day 3 with a higher number of 5 cells per 10 field of view and was resolved within day 5. Despite the differences in onset and peak neutrophil levels, both mares' inflammatory responses resolved within the same timeframe and is still within the normal range.