Presence of back arch in headlocks

An indicator of lameness and hoof lesions in dairy cattle?

Abstract

Observation of an arched back while standing and walking is 1 criterion for assessing dairy cow lameness. Objectives of these projects were to evaluate back arch and its association with locomotion score (LS) and hoof lesions. On a single 200-cow farm, digital photographs were taken of cows with locomotion scores greater than 1 while stanchioned and walking, and analyzed for degree of back arch. One pen of cows was observed 5 times while stanchioned to evaluate "time in headlock" effect on presence of back arch. Angle of deviation from flat-back was not significantly associated with LS; however, there was a trend for cows with a score of greater than 2 to have back angles deviating from flat. The proportion of time a cow was observed with a back arch was greater for lame cows vs non-lame cows. In a second herd, back arch data were collected on 233 cows while stanchioned, and hoof lesion data were collected on 141 cows. Cows with a back arch were 2.1 times more likely to have a hoof lesion (P=0.04), and there were more cows with hoof lesions with increasing LS (P less than 0.0001). Back arch could be used as a screening test for lameness.