POSTPARTUM PATHOLOGIES AND ORIGIN OF INFERTILE COWS IN DAIRY CATTLE IN THE MEXICAN HIGHLANDS

Infertility in dairy cows under intensive productive systems is a growing problem and is one of the main causes of culling. The objective was to determine the origin of infertility in dairy cows under intensive productive systems from the Mexican highlands with postpartum pathologies. In this experiment 1,110 housed Holstein cows were studied. Cows were divided by calving number: First (n=389); Second (n=296) and three or more (n=425). Statistical analysis: comparison of means (Anova model) and univariate analysis. High percentage of the cows remained healthy after calving (80.5%); however, 15.6% of these cows were infertile. The prevalence of pathologies was 19.5%, and 26.3% of these cows were infertile. Cows with reproductive pathologies had a higher percentage (p<0.05) of infertile cows (25.0%). The infertility increased with the number of calvings, cows with three or more calvings and with reproductive pathologies had the highest percentage of infertile cows compared with those of second and first calving (39.0%, 30.0% and 14.0%, respectively). Second calving cows (OR: 2.24 95% CI: 1.06-4.95) and cows of three or more calvings and that presented reproductive pathologies (OR: 1.95 95% CI: 1.03-3.71) were identified as risk factors. In conclusion, cows that presented reproductive pathologies had the highest percentage of infertile cows and the risk of remaining infertile increased up to 4 times, especially if they presented more than 2 calvings. The percentage of infertile cows with postpartum pathologies could not be fully explained, leaving 15.6% of infertile cows with different origins.