Evaluation of Claw Horn Lesions frequency in some dairy herds of Iran.

Infectious and non-infectious claw lesions cause lameness in dairy cows. The primary and main causes of lameness in dairy cows are sole ulcer, hemorrhage and white line disease. The present study was conducted to provide an initial estimation of the occurrence of claw horn lesions in Iranian dairy cows. The study was carried out in four dairy farms with hoof care program (hoof trimming, locomotion scoring, footbath, bedding management, heat stress management, insect control, acidosis control indices, and nutrition) for the past five years. All the relevant data from hoof examinations and trimming between 2012 and 2013 were recorded and extracted. Reports were presented descriptively with mean and standard deviation, and if necessary, statistical comparison was performed using the chi-square test, considering values of P<0.05 as statistically significant. Overall, data from 20,222 cows were examined. White line disease in 2013 (703 cases, equivalent to 7.19% of cows) were higher than 2012 (391 cases, equivalent to 4% of cows), as well as sole ulcer (941 cases, equivalent to 9.63% in 2013 and 816 cases, equivalent to 8.35% in 2012). However, a consistent pattern was not observed regarding toe ulcer. The results of the present study indicate a higher occurrence of sole ulcer and white line disease in autumn.