Effects of space allowance on the behavior and physiology of cattle temporarily managed on rubber mats.

Dairy cattle managed in some pasture-based systems, such as in New Zealand, are predominantly kept outdoors all year around but are taken off pasture for periods, especially in wet weather to avoid soil damage. The use of rubber matting for such stand-off practices is becoming more common to improve animal welfare, and our objective was to investigate the effects of different space allowances on cow behavior and physiology when managed temporarily on rubber mats during a weather-induced stand-off period. Thirty pregnant, nonlactating Holstein-Friesian dairy cows were divided into 6 groups of 5 and exposed to 6 treatments following a Williams designed 6×6 Latin square. The treatments consisted of 6 space allowances on a 24-mm rubber surface during a simulated weather-induced stand-off period: 3.0, 4.5, 6.0, 7.5, 9.0, and 10.5 m(2)/cow. The stand-off period consisted of 18 h in the treatment pens followed by 6 h at pasture to allow for their daily feed intake (no feed was available during stand-off, following normal farm practice), for 3 consecutive days, with 6 d of recovery on pasture between treatments. When cows had more space available during the stand-off period, they spent more time lying on the rubber mats and less time lying on pasture during their daily 6-h feed break. Mean lying times (24 h, pasture and rubber mats combined) for the different space allowances were for 3.0 m(2)=7.5 h, 4.5 m(2)=10.2 h, 6.0 m(2)=11.9 h, 7.5 m(2)=12.4 h, and 10.5 m(2)=13.8 h. At 6.0 m(2) of space allowance per cow, the animals spent similar times lying per 24 h as when the cows were on recovery on pasture in between treatments (11.9 and 11.2 h, respectively). Aggressive interactions and nonaggressive lying disturbances were more frequent at lower space allowances (aggressive interactions decreased by 35% from 3.0 to 4.5 m(2)/cow, with a slower decline thereafter). Cows were dirtier after the stand-off period, particularly at lower space allowances. All cows had higher gait scores after the stand-off period; however, this change was unaffected by space allowance and very minor. Stride length, plasma cortisol, and body weight were all unaffected by the stand-off period and space allowance. The results suggest that to reduce aggressive behavior and maintain adequate lying times, dairy cattle managed temporarily on rubber matting for up to 18 h per day, without feed, should have a space allowance of at least 4.5 to 6.0 m(2) per cow.