Estrus detection on different thoroughbred crossbreed horses with vaginal smear and vaginal acidity method

Abstract Breeding manipulation season in racehorses is required to ensure the birth at the specific period (August-December), which will maximize the foal’s age when participating in their first race (July). Therefore, it is important to time the mating of mares using highly accurate estrus detection methods. This research was conducted to identify the differences data using vaginal smear and pH vagina of Thorougbred crossbreed mares in estrus and anestrus phases. Fifteen multiparous mares were conducted with a period of estrus of 19-22d. The result data showed significant differences (P<0.05) in the vaginal cell distribution patterns at each phase of the estrus cycle. The superficial cells predominate (92.43±5.14%) in the estrus phase while significant parabasal cells (87.89±3.09%) predominate in the anestrus phase. The results also showed a significant difference (P<0.05) in vaginal pH which was much more alkaline (8.71±0.25) in the estrus phase while more significantly acidic-normal (6.02±0.26) in the anestrus phase. However, the results showed no difference both in vaginal smear and pH vagina based on pedigree group. Finally, the pattern of superficial cells being more common and vaginal pH levels being higher during estrus may offer a new way to find out when an equine is in estrus.