Evaluation of claw health of dairy cattle housed in dirt lot vs free stall in TMR systems in the central region of South Africa

Abstract

Claw health is arguably an important factor in dairy cow welfare. Evaluation is important as an early indicator of lameness in dairy cattle. In South Africa, information on claw lesions is not routinely collected and not yet included in genetic evaluations. The study aimed to evaluate the claw health of dairy cattle housed in dirt lot vs free stall under the TMR systems in the central regions of South Africa. The current study evaluated data 10 commercial dairy farms having a dirt lot or, free stall system. Data were collected by professional claw trimmers from January 2011 to May 2018. The scored claw disorders included heel erosion (E), digital dermatitis (DD), foot rot (F), hairy attack (HA), axial fissure (AX), sole ulcer (U), toe ulcer (TU), white line (WL), sole fracture (SF) and corkscrew (C). The edited data were statistically analysed for all lesions with years, infectious vs non-infectious, season, dirt lot vs free-stall as variables and season by housing interactions. A significance test after chi-square testing was also performed. The overall prevalence rate for all the lesions among trimmed cows was the highest in 2017 (30%) and 2016 (28%), compared to 2014 (17%), 2015 (18%) and 2018 (7%). The occurrence of infectious (59%) lesions (P < 0.001) was higher compared to non-infectious (41%) across years in all farms. Digital dermatitis (53%), E (35%) and C (41%) were the most frequent lesions (P < 0.001), reported in 70 to 80% of the total herds, while other lesions were relatively low. Heel erosion was significantly influenced by free stall farms, while DD was not influenced by housing systems (P > 0.002). Similarly, C was also not influenced by housing systems (P > 0.002). Heel erosion was significantly influenced (P < 0.001) by Autumn and Spring, with profound effects marked in Spring (8.4%). Summer and free stalls interactions significantly influenced E (P < 0.001). The current study suggests that seasons and housing type have notable effects on the prevalence of claw lesions. The findings indicate that different lesion types having significantly different risk factors, which will require intervention and specific management for ensuring claw health.