Meta-analysis of prevalence and associated risk factors for lameness in dairy cattle across tropical Asian nations

Context. Lameness in dairy cattle affects the health, welfare, performance, and profitability of dairy farms. Being multifactorial in nature, several animal and farm-level risk factors influence the severity and prevalence of lameness. Aims The objective of the present meta-analysis study was to provide a pooled estimate of the prevalence and identification of the potential risk factors associated with lameness in dairy cattle across tropical Asian countries. Methods. A literature search reporting prevalence data for lameness in dairy cattle of tropical Asian countries including India, Bangladesh, Pakistan, Malaysia, Nepal and Thailand for the past 21 years (2000-2021) was collected by using appropriate keywords from the electronic databases. After removing outlier studies, a meta-analysis of 38 studies published in English was performed under a random-effects model by using the meta package (metaprop function) in R software. Key results. The pooled estimate of the overall prevalence of lameness was 15.13% (95% confidence interval [CI] = 13.01, 17.53). High heterogeneity was found in the prevalence estimates among the published studies (P < 0.05). The pooled prevalence for lameness-related lesions was, for overgrown hooves 34.42% (95% CI = 23.41, 47.42), interdigital 28 hyperplasia 9.73% (95% CI = 5.84, 15.78), white line disease 6.91% (95% CI = 3.54, 13.05) and sole ulcer 6.84% (95% CI = 3.87, 11.83). The prevalence of lameness was higher in cows at parity three (23.03%) and at parity greater than or equal to 4 (31.68%) than at first and second parity. Breed of an animal, lower body condition score (BCS), housing and floor type, and season also had a significant effect on the pooled prevalence of lameness (P < 0.0001). Conclusions. The findings of the present study showed that lameness is prevalent across the tropical Asian countries and there was a significant association of risk factors such as housing, floor, hygiene, and animal nutrition with lameness in dairy herds. Implications. Meta-analysis study indicated that there is a need to adopt better management practices to minimise the incidence of lameness in dairy animals.