Modeling the Effect of Lameness on Culling of Dairy Cows in Tehran Province

Objective-to assess the effect of lameness on culling of dairy cows in tehran province. design- historical cohort study. study population and procedures- 7067 first- and second-parity holstein dairy cows that calved from march, 21 2007 to march, 20 2008 were until next calving or culling. logistic regression was conducted data. results-the overall lactational culling rate for eligible cows in the study was 22.09% (95% ci: 19.26-24.9%). lameness was an important factor in the model and increased odds of culling (or= 1.32; 95% confidence interval = 1.15-1.51). moreover, parity, 60-day cumulative milk yield, and herd size increased culling odds. we did not find evidence for a significant effect of calving season on culling. conclusion- lameness is an important factor in culling decision in dairy herds in this area.