Associating mobility scores with production and reproductive performance in pasture-based dairy cows

摘要

Lameness in dairy cows can have significant effectson cow welfare, farm profitability, and the environment.To determine the economic and environmental consequencesof lameness, we first need to quantify its effecton performance. The objective of this study, therefore,was to determine the associations of various productionand reproductive performance measurements (includingmilk, fat, and protein yield, somatic cell count, calvinginterval, cow death, or cow slaughter), and mobilityscores in spring-calving, pasture-based dairy cows. Wecollected mobility scores (0 = good, 1 = imperfect, 2= impaired, and 3 = severely impaired mobility), bodycondition scores, and production data for 11,116 cowsfrom 68 pasture-based dairy herds. Linear mixed modelingwas used to determine the associations betweenspecific mobility scores and milk, fat and protein yield,and somatic cell count and calving interval. Binomiallogistic regression was used to determine the associationbetween mobility score and cow death, or slaughter.Significant yield losses of up to 1.4% of the averageyield were associated with mobility score 2 and yieldlosses of up to 4.7% were associated with mobility score3 during the early scoring period. Elevated somaticcell count was associated with all levels of suboptimalmobility during the late scoring period. Cows with amobility score of 2 during the early scoring period wereassociated with longer calving interval length, whereasonly cows with a mobility score of 3 during the latescoring period were associated with longer calving intervallength. Cows with a mobility score ≥1 were morelikely to be culled during both scoring periods. Ourstudy, therefore, shows an association between specificmobility scores and production and reproductive performancein spring-calving, pasture-based dairy cowsscored during the summer grazing period.