Endometritis subclínica y tasa de gestación en vacas lecheras en México

Abstract

The present study determined the prevalence of subclinical endometritis and its effect on pregnancy rate in intensively managed dairy cows. Between d 35 and 45 postpartum, 237 cows with no uterine pathologies judged to have completed uterine involution and no abnormal vaginal secretions were selected. Endometrial cytology samples were taken from each cow using the Cytobrush technique, and smears were stained with Diff-Quick. A total of 200 sample cells were counted and the proportion of polymorphonuclear leukocytes (PMN) was estimated. Cows with ≥6 % PMN were considered to have subclinical endometritis; 43 % (103/237) of cows sampled met this criterion. Cows with pathological puerperium had a higher probability of undergoing subclinical endometritis than cows with normal puerperium (60 vs 36 %, respectively; odds ratio= 2.69). Cows not presenting subclinical endometritis had a higher pregnancy rate at first service than cows with this condition (31.4 vs 20.0 %, respectively; odds ratio= 2.02), and the percentage of pregnant cows at d 120 postpartum was higher in cows not experiencing subclinical endometritis than in cows with this condition (51.6 vs 37.9 %, respectively; odds ratio= 1.98). It concludes that 43 % of cows suffered subclinical endometritis between d 35 and 45 postpartum, which decreased pregnancy rate at first service, as well as cumulative pregnancy rate at d 120 postpartum.