A summary of the reasons why farmers cull cows.

A study was conducted to determine why cows are culled, whether cows are culled for multiple reasons, and whether farm characteristics can help explain why cows are culled. The primary reasons for culling were reproduction (i.e., failure to conceive), mastitis, and low production. For 35% of all cows that were culled, a secondary reason for culling was assigned by the farmer, and, for 11% of all cows that were culled, a tertiary reason was recorded. Using a weighting factor of 5:3:1 (primary:secondary:tertiary reasons for culling), a culling score was computed for each reason within a herd. Reproduction was the primary reason for culling, production was second, and mastitis was third. Much variation existed as to why dairy farmers culled cows. Computed mean culling scores suggested that culling for mastitis was lower in high producing Holstein herds, and culling for abortion was higher in high producing Holstein herds. Culling for reproduction was higher in high producing Holstein herds, and culling for production was lower in high producing Holstein herds. Culling for mastitis and production were significantly lower in high producing Holstein herds than in non-Holstein herds. A system that allows the documentation of multiple reasons for culling and the computation of a composite score appears to be reasonable for the assessment of culling management.