Prevalence of Subclinical Laminitis and Its Effects on Reproductive Performance in Lactating Cows in Thailand

Abstract

The objectives of this study were to investigate the prevalence of subclinical laminitis and to evaluate its effects on reproductive performances in dairy cows in Thailand. Ninety-eight lactating cows from 22 smallholder dairy farms and 138 lactating cows from one large scale dairy farm were assessed for subclinical laminitis by evaluating lesions after hoof trimming. Hemorrhagic lesions of the sole and white line area were evaluated. Any appearance of sole hemorrhage or white line hemorrhage scoring 2 on one or more claws was defined as a case of subclinical laminitis. Reproductive data were recorded and analyzed using subclinical laminitis as the main effect with other covariates. The prevalence of subclinical laminitis in the lactating cows raised on smallholder dairy farms and on a large scale dairy farm was 38.8% and 42.0%, respectively. The calving to conception interval (CCI) of laminitis cows was significantly increased (p<0.05) on the smallholder dairy farms (time ratio; TR = 1.32) and on the large scale dairy farm (TR = 1.21). The estimated median times of CCI between non-laminitis and laminitis cows on the smallholder dairy farms and on the large scale dairy farm were 119.8 and 158.6 days, and 134.1 and 163.6 days, respectively. These results showed that subclinical laminitis was highly prevalent in dairy cows in Thailand, and subclinical laminitis had negative effects on reproductive performance by increasing the time span of CCI.