The effect of housing tiestall dairy cows in deep-bedded pens during an 8-week dry period on gait and step activity.

Increasing locomotor activity can improve leg health and decrease the prevalence of lameness in dairy cows. The dry period offers an opportunity to provide alternative housing to tiestall (TSL) cows that can increase locomotor activity. The objective was to determine whether housing TSL dairy cows in a deep-bedded loose pen (LP) during the 8-wk dry period affected gait and step activity. Twenty cows, paired by parity and calving date, were assigned at dry-off to a deep-bedded LP or a TSL. Step activity was measured by leg-mounted pedometers. Cows were walked 1×/wk on a test corridor, and video recordings of gait were taken. Six aspects of gait were scored on a 0-to-5 scale (interval: 0.1 unit): tracking up, joint flexion, back arch, asymmetric step, swing, and reluctance to bear weight. Overall gait was also scored using a 1-to-5 scale (interval: 0.5 unit). Data for gait were analyzed based on the change in gait between dry-off and calving. Daily step data were averaged per week of the dry period. Analyses were performed using a mixed model with treatment, term, and block as fixed effects and cow nested within treatment and block as a random effect for step data. The same model, omitting the fixed effect of week, was used for gait variable analyses. There was no difference in step activity between LP and TSL cows (842.1 ± 88.86 vs. 799.5 ± 76.92 steps/d, LP vs. TSL, respectively). Only joint flexion yielded a treatment difference, with LP cows improving over time and TSL cows worsening (-0.4 ± 0.15 vs. 0.2 ± 0.15). Possibly owing to individual variation in motivation to perform locomotor activity, higher levels of step activity, independent of treatment, tended to be correlated with improvements in swinging out, tracking up, joint flexion, and overall gait score. The increased space allotted to LP cows may have allowed for a larger range of motion for each step, and the denser lying surface may have provided a cushioning effect when transitioning between rising and lying, all of which can improve joint health, reflected in improved joint flexion. Further investigation is warranted into the potential benefits of alternative housing on cow comfort, movement opportunity, and cow condition.