Effects of free-choice pasture access on lameness recovery and behavior of lame dairy cattle.

According to the literature, mild lameness in dairy herds may exceed 20% and severe cases could be 5 to 10%. This not only reflects negative on the economy of the enterprise, but also on animal welfare because of the pain the animal has to endure, and also due to implications to feeding, lying and locomotion. Therefore, methods to reduce lameness are required to reduce prevalence in the herd. To that effect, it has been shown that free-choice access to pasture may benefit lame cows by providing a softer and more comfortable lying and standing surface. This has however not been well explored, and therefore the authors cited investigated whether a 7-week period of free-choice pasture access would improve lameness recovery and affect the lying behaviour of lame cows. 

Lactating Holstein cows, all clinically lame diagnosed, were housed inside a freestall barn and allocated to one of two treatments which balanced for gait score, parity and lameness history. The two treatments were: (1) free-choice access to pasture (PASTURE), or (2) indoor housing only (INDOOR). The cows were gait scored weekly by an observer blind to treatment, using a 5-point numerical rating system (NRS 1 = sound; NRS 5 = severely lame), and hoof inspections were performed by professional trimmers at the start and end of the 7-week period. Lying behaviour was assessed using accelerometers. The cows were then categorized as either having a sound period (NRS less than 2 over two consecutive weeks) or remaining lame.

The cows on average spent about 15% of their total time on pasture, with much of this time spent outside at night. Over the 7-week period, 42% of the cows had at least one sound period (PASTURE: 55.6%; INDOOR: 26.9%), but this was more likely for cows with pasture access. PASTURE cows lay down for less overall time than INDOOR cows (14 vs 12.5 hours per day) and spent more time standing on pasture (74%) than when indoors (47%).

The results suggest that lame cows will use pasture when provided with free-choice access, primarily at night, and that access to pasture aids in lameness recovery. It is recommended that future research should investigate longer-term effects on the recovery of hoof lesions and re-occurrence of lameness cases.