Disorders of the claw and their association with Laminitis in smallholder zero-grazed dairy cows

Abstract

A cross-sectional study was carried out in which 300 zero-grazed dairy cows from 32 smallholder dairy units were examined for claw lesions in the peri-urban areas of Nairobi, Kenya. The objective of the study was to determine the characteristics of claw disorders and their association with laminitis. Lameness for each cow was determined by assessing the locomotion score through a prescribed locomotion scoring system. Each cow was restrained in a crush and the claws thoroughly washed and examined for any external claw lesions or disorders including signs of laminitis. About 1-2 mm thickness of the horn of the sole for each claw was trimmed to confirm laminitis by presence of sole haemorrhages. Data was analyzed using Genstat statistic software. Prevalence of laminitis was 70.3% out of which 49.3% was subclinical laminitis and 21.0% was chronic laminitis. Claw deformities found to be strongly associated with chronic laminitis were claw overgrowth (χ2=96.69, r=0.6, P<0.0001), horizontal grooves (χ2=61.27, r=0.5, P<0.0001), concave claws (χ2=59.39, r=0.4, P<0.0001), flat claws (χ2=57.87, r=0.5, P<0.0001), presence of sole haemorrhages (χ2=50.16, r=0.4, P<0.0001), double soles (χ2=42.57, r=0.4, P<0.0001) and white line separation (χ2=37.78, r=0.4, P<0.0001), while sole bruising was moderately associated with chronic laminitis (χ2=11.02, r=0.2, p=0.0009). Sole haemorrhages were the only lesions strongly (χ2=89.45, r=0.6, P<0.0001) associated with subclinical laminitis. It was therefore concluded that chronic laminitis was strongly associated with deformity types of claw disorders coupled with diffuse sole haemorrhages, while subclinical laminitis was strongly associated with sole haemorrhages only.