Healing of claw lesions in dairy cows under the conditions of alpine mountain pastures

The field study investigated severity, localisation and incidence of claw l esions of dairy cows and their healing process during a period of three mon ths on selected mountain pastures in the central part of Switzerland. In 60 cows, which were at least 120 days in their lactation, the healing process was compared with the biochemical profiles. In 141 cows 197 claw lesions w ere recorded. Diagnosed were only sole ulcers (38 %) and white line lesions (62 %). In the first and second half of the summer term, the number of cla w lesions was equal, although more severe lesions occurred mainly during th e second half (89 %). The lesions were treated surgically and the affected claw was elevated on a wood block or a plastic shoe. Average time for forma tion of a close layer of horn was 14 days. A delayed healing process was ob served in dairy cows with an milk yield over 5500 kg per lactation, as well as in the second half of the summer term. Cows with a delayed healing proc ess had significantly higher concentrations of free fatty acids and beta-hy droxybutyrate, and higher plasma enzyme activities for AST than cows with a dequate healing process. This indicates that cows with a relatively high mi lk production touch upon the limits of their physical capacity under harder conditions on alpine pastures, which may affect also the healing process o f claw lesions.