Reducing labour inputs on dairy farms mean it can be difficult to find time to spend observing cows, looking for the tell tale signs of illness.

But activity monitors promise to reduce this, helping farmers spot changes in cow behaviour which could be signs of bulling or lameness. And to assess whether these systems offer the benefits they claim to, Nicola Blackie of Writtle College, Chelmsford, studied lying behaviour and locomotion score in 59 Holstein cows.

The 59 cows were grouped according to locomotion score, with scores based on the 1-5 scale, although there were too few cows scoring 4 and 5 to be used in the study, explained Ms Blackie.

"Cows with locomotion score 3 spent about two hours/day longer lying down than cows with locomotion score 1 and locomotion score 2, although there was not effect of locomotion score on time spent active. Additonally, this increased lying time resulted in lower yields, with locomotion score 3 cows producing 8 and 6.4 litres less than locomotion score 1 and 2 cows respectively," she added.

Overall, these results suggest that lying time measured using an activity monitor has the potential to detect lameness in dairy cattle as indicated by increased lying times.