A field investigation of the use of the pedometer for the early detection of lameness in cattle.

The efficacy of the pedometer to predict lameness earlier than the appearance of the clinical signs in a herd of dairy cows was investigated by correlating pedometric activity (PA) with clinical cases of lameness. The computer program was set to identify cows with a reduction of 5% or more in PA compared with their own previous 10 days average; these animals were then examined for clinical lameness. At the same time, every lame cow was checked to see if and when its PA was reduced. Forty-six cows showed a reduced PA; 38 cases of lameness were identified by either a reduction in PA or clinical observation; of these, 21 lame cows (45.7%) showed a reduction in PA of 5% or more, 7 to 10 days prior to the appearance of clinical signs. This cohort comprised 55.3% of the lame cows. In 92% of the lame cows identified by PA, the decrease was above 15%.