Cow- and farm-level risk factors for lameness on dairy farms with automated milking systems.

Discipline: lameness; Key words: automated milking systems, lameness prevalence, animal welfare, stall design.

Lameness is a major concern to animal health and welfare within the dairy industry. There are several causes and risk factors. In this paper the authors addressed factors associated with automated milking systems. The paper by Dr R. Westin and colleagues was published in the Journal of Dairy Science, Volume 99 of 2016, page 3732-3743, with the title: Cow- and farm-level risk factors for lameness on dairy farms with automated milking systems.

The objectives of the study were to describe the prevalence of lameness in high-producing cows on farms with automated milking systems and to identify the main risk factors. The authors visited 36 farms with automated systems across Canada and the US. Farm related factors investigated were stall design, bedding, flooring and stocking rates. These were recorded by trained observers. Cows were scored for lameness, leg injuries, body condition (BCS), and body size, measured by hip width and rump height.

The mean herd prevalence of clinical lameness was 15%, with a range between farms of 2.5 to 46%. Stall width relative to cow size and lactation number was found to be the most important factors associated with lameness. Not fitting the average stall width increased the odds of being lame 3.7 times in multi-lactation cows. A narrow feed alley (less than 430 cm), an obstructed lunge space, a low BCS (less than 2.25 compared with 2.75 to 3.0) and the presence of hock lesions were also identified as important risk factors for lameness. Only one of 36 farms had stalls of adequate width and length for the cows.                                          

For lameness prevention, the authors concluded that more emphasis should be placed on either building stalls of appropriate width or selecting for smaller-framed cows that fit the existing stalls.