Prevalence, risk factors, and reproductive consequences of subclinical endometritis in New York State dairy farms
This study used 38 large New York State dairy farms to examine prevalence of subclinical endometritis (SCE), defined as uterine inflammation without clinical signs (neutrophils ≥10%). Cow- and herd-level risk factors and possible reproductive consequences of SCE were examined. 25.8% of the cows sampled had SCE (202/779). SCE herd prevalence ranged from 4.8-52.6%. Cow-level risk factors included ketosis (OR=3.83); puerperal metritis (OR=1.86); and high milk production in 1st lactation animals. Herd-level risk factors for SCE included straw calving pen bedding and bedded pack housing for postfresh animals. Reproductive consequences of SCE included increased days open in multiparous animals. This effect was not seen in primiparous animals. Both groups had decreased fertility at first service (OR=0.61). Our findings demonstrate that subclinical endometritis is common in commercial dairy farms and that certain diseases and management practices contribute to SCE. In addition, SCE does seem to have reproductive consequences, especially in older animals.