Equine endometrial cytology and bacteriology: effectiveness for predicting live foaling rates.

The research examined the effectiveness of endometrial cytology and bacteriology in predicting live birth rates in mares. Positive correlations were identified between certain threshold values of uterine polymorphonuclear neutrophils (PMNs), presence of bacterial growth, and reduced rates of live foals.

Objective of the Study

The main aim of the study was to determine:

• The existence of a threshold percentage of uterine polymorphonuclear neutrophils (PMNs), beyond which a significant reduction in live foaling rate is observed;
• The correlation between positive bacteriology results and live foaling rates;
• The correlation between combined positive cytology and bacteriology results and live foaling rates.

Methodology

• Endometrial swabs were collected from 1621 mares, regardless of age, history or parity,
• The collection process was conducted during a single breeding season using guarded endometrial swabs,
• The swabs, 2660 of them, were collected from commercial stud farms by five veterinarians,
• Each swab was subjected to cytological and bacteriological analyses,
• The live birth rates were recorded subsequently,
• Data of PMNs of total cells counted or categories of bacterial growth to live birth rates were analysed using Pearson’s chi-squared test.

Findings

According to the analysed data:

• A threshold value of ≥ 1% PMNs was associated with significantly reduced live foaling rates,
• The presence of a single bacterial isolate was associated with reduced live foaling rates,
• A combination of both, 1% PMNs and single bacterial isolate, were linked with significantly reduced live foaling rates.

The study concluded that positive cytology alone, positive bacteriological culture alone, or a combination of both are indicative of a mare’s likelihood to produce a live foal. This can assist in identifying mares at risk of early embryonic death or those who may conceive but abort in late gestation.