The relationship between cycle stage and results of uterine culture in the mare

Abstract

A total of 368 uterine swabs were taken from mares in heat (n = 202) and from mares that were not in heat (n = 166). From 72 of the mares, two swabs were taken; one during either seasonal anoestrus or dioestrus, and one during oestrus. Swabs were taken during anoestrus/dioestrus in 94 other mares and during oestrus in the remaining 130 mares. Bacteriological cultures were done aerobically and classified as negative, insignificant or significant. There was a trend for more positive cytological specimens during oestrus than during anoestrus/dioestrus. The proportions of significant cultures were 12 of 202 (5.9%) in oestrous mares and 14 of 166 (8.4%) in anoestrous/dioestrus mares. Generally more insignificant than negative cultures were obtained during oestrus compared to anoestrus/dioestrus. Seven of 27 cultures that were classified as significant were associated with positive cytological specimens, and only 2 of 16 specimens that yielded pure cultures of E. coli contained neutrophils. Although the culture results did not differ significantly between the cycle stages, oestrus should be the preferred time for uterine examination.