title: Prevalence of endometritis and its effects on reproductive performance of dairy cows.
abstract: Hostein cows (n=141) in five commercial dairy herds in central New York were examined for endometritis by examination of endometrial aspirates for presence of inflammatory cells, principally neutrophils, by endometrial cytology at 40-60 days postpartum. The prevalence of cytologically-diagnosed endometritis was 53%; within herds the prevalence varied from 37 to 74% (P=0.02). There was excellent agreement between two examiners (Kappa=0.864; P<0.0001). Parity did not influence prevalence of endometritis (P=0.53). Cytologically diagnosed endometritis was associated with profoundly impaired reproductive performance; Kaplan-Meier survival analysis revealed lower overall pregnancy rate (P<0.0001). Median days open was 206 for cows with endometritis and 118 for cows free of the condition. Overall, 76% of cows in this study became pregnant by 300 days postpartum; 63% of cows with endometritis and 89% of cows without endometritis were confirmed pregnant by 300 days postpartum (P<0.003). (For these two groups, 69, and 90% respectively, became pregnant during the duration of the study). Pregnancy to first service percentage was lower (11 versus 36%; P=0.001) for cows with than without endometritis, and these cows required more services before 50% became pregnant (3 versus 2; P=0.006). In a second study using 22 cows in a university-owned herd, the prevalence of cytological evidence of inflammation was 100% at 2 weeks postpartum, and dropped to 89, 58, and 41% at 4, 6, and 8 weeks, respectively. Endometritis diagnosed by endometrial cytology late in the voluntary waiting period was highly prevalent and exerted a profoundly detrimental effect on subsequent reproductive performance, making this condition potentially extremely costly to the North American dairy industry.
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853-6401, USA. rog1@cornell.edu
authors.forename: Robert O
authors.initials: RO
authors.lastname: Gilbert
authors.forename: Sang T
authors.initials: ST
authors.lastname: Shin
authors.forename: Charles L
authors.initials: CL
authors.lastname: Guard
authors.forename: Hollis N
authors.initials: HN
authors.lastname: Erb
authors.forename: Marcel
authors.initials: M
authors.lastname: Frajblat
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology*; D003581:Cytodiagnosis; D004716:Endometritis / Q000175:diagnosis / Q000453:epidemiology / Q000662:veterinary*; D005260:Female; D007247:Infertility, Female / Q000209:etiology / Q000662:veterinary; D009504:Neutrophils; D049590:Postpartum Period; D011247:Pregnancy; D012098:Reproduction; D013997:Time Factors