Consequences and economics of metritis in Iranian Holstein dairy farms

The objectives of this study were (1) to describe the risk factors, incidence, and productive and reproductive consequences of metritis in dairy cows, and (2) to estimate the financial losses associated with metritis using data gathered from 4 Holstein dairy farms in Isfahan, Iran. Calving records from March 2008 to December 2013, comprising 43,488 calvings, were included in the data set. The effects of metritis on productive and reproductive performance were analyzed using a mixed linear model for primiparous and multiparous cows separately and in an overall data set (all cows combined), whereas risk factors on metritis incidence were examined using a multivariable logistical regression model for the overall data set. The incidence of metritis per cow per year was 13.2% on average and ranged from 9.0 to 15.8%. Results of logistic regression analysis demonstrated that calving year, parity number, calving season, twinning, dystocia, and retained placenta were significantly associated with the occurrence of metritis, whereas previous metritis incidence did not show an association. Greatest odds of metritis occurred in first-parity cows that calved in winter and had retained placenta, twinning, and dystocia in recent years. A case of metritis significantly reduced the 305-d milk yield in primiparous and multiparous cows and overall, but had no significant effects on 305-d fat and protein percentages in either primiparous or multiparous cows. Overall, a case of metritis reduced 305-d milk yield by 129.8±41.5kg/cow per lactation. The negative reproductive effects due to metritis were smaller and nonsignificant for primiparous cows compared with multiparous cows. Overall, a case of metritis increased days open and number of insemination per conception by 16.4±1.2 and 0.1±0.0 per cow per lactation, respectively. Among the individual farms, metritis costs ranged from $146.4 to $175.7 with a mean of $162.3/case. The model to calculate metritis costs proposed here could be used to estimate economic losses for metritis in other developing countries, where farm productive and economic data are generally scarce.