Rate of Horn Growth, Wear and Sole Thickness of Dairy Cattle in a Free Stall Barn with Concrete and Rubber Flooring

To compare horn growth, wear and sole thickness, twenty-four mature dairy cows were ranked in order according to lactation number and calving date. Using a randomized block design, each group of two cows was randomly assigned in ranked order to either the experimental group (housed on rubber mat, group R) or the control group (housed on concrete, group C). The 12 cows in each group were selected to achieve equal parity. The two groups were examined at 2-week intervals over a 12-week period, Cows in group C had a significant increase in claw horn growth over the study period compared to the group R. There was a non-significant difference in wear between cows in the 2 groups at the end of the study, with cows in the group C showing most wear. These findings suggest that there was a compensatory increase in horn production in response to accelerated claw horn wear in group C. This was further supported by the fact that there was only a small but not significant difference in sole thickness between the 2 groups at the end of the study with the cows in group C having slightly thinner soles. Within group comparison of claw measurements recorded at the beginning (week 0-2) and end (week 10 -12) of the trial, cows in both groups showed significant increases in claw length indicating that overall growth exceeded wear in both groups. Results of the study indicate a possible protective effect of a rubber walking surface (versus concrete) against claw horn wear. Cows on concrete showed accelerated growth that did not fully compensate based on a tendency for increased wear and slightly thinner soles