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Effect of stall size, tie-rail position, and chain length on cow injuries and cleanliness in Eastern Canadian tie-stall farms
Lying stall configuration affects cow comfort. Lack of space for the cow may result from old facilities (stall size) and from efforts to keep the cow cleaner (tie-rail position). To evaluate effects of not following recommendations for stall configuration on cow comfort, 40 lactating Holstein cows from each of 100 tie-stall dairy farms (Quebec, n=60; Ontario, n=40) were measured (hip height and hook bone width) and evaluated for neck, knee and hock injuries, and udder, flank and leg cleanliness. Data collected about stall configuration included bed length, stall width, tie-rail height and position, tie-chain length and manger wall height and these were compared with Canadian recommendations. Data were analyzed using Proc GLIMMIX of SAS with a binomial distribution. Only 21.1% of cows had a tie-chain long enough to meet recommendations. A standard tie-rail forward position (≥35 cm compared to the bed length) was observed for 16.8 % of cows. Each 10-cm increase of stall width closer to the recommendation decreased odds of neck injury by 11.6% (P=0.008) but increased odds of flank and leg dirtiness by 35.6% (P=0.0006) and 16% (P=0.0006), respectively. Each 10-cm increase in bed length tended to decrease odds of knee injuries by 10.4% (P=0.08) but increased odds of udder dirtiness by 35.6% (P=0.02). Increasing tie-rail height by 10-cm closer to the recommendation increased odds of neck injuries by 22% (P=0.008). Each 10-cm move forward of the tie-rail decreased odds of neck and knee injuries by 41.8% (P=<0.0001) and 17.2% (P=0.0001), respectively, but increased by 20.2% (P=0.03) odds of udder dirtiness. Each 10-cm lengthening of the tie-chain decreased odds of neck (8.3%, P=0.02), knee (9.9%, P=0.002), and hock (8.3%, P=0.003) injuries. A higher than recommended manger wall was not related to cow injuries (P>0.1) but increased by 3.7% (P=0.02) odds of udder dirtiness. Although recommendations for tie-rail height need further testing, these results suggest that, even if associated with decrease in cleanliness, simple modifications by dairy producers to stall configuration (forward tie-rail position and increased tie-chain length) to meet current recommendations would result in a decrease in neck, knee and hock injuries and increasing cow welfare.
Keywords: tie-stall, injuries, cleanliness