Hock lesions, cow hygiene, and compost quality in compost-bedded pack barns in Germany

The aim of the study was to evaluate the prevalence of hock lesions and cow hygiene as a cross-sectional study in dairy cows housed in compost-bedded pack barns (CBPs) in southern Germany. The effects of season, compost variables, and housing conditions on cow hygiene and hock lesion prevalences were also investigated. Eight farms that housed their cows in CBPs were visited once in the cold season and once in the warm season between January and December 2023. All cows (cold season n = 592; warm season n = 613) were scored for hygiene and hock lesions at each visit. Compost samples were collected for laboratory analysis, and the quality of the compost-bedded pack and condition of the lying surface and concrete walkways were assessed. The udder was the cleanest body zone in both seasons; poor udder hygiene (too dirty score) occurred in 15.0% of cows in the cold season and 7.5% in the warm season (p ≤ 0.05). Only 1% of the cows had a hairless area on a hock in the cold season compared with 3.8% in the warm season; 0.2% of the cows also had swelling of the hock in the warm season (p ≤ 0.05). The compost variables that impacted cow hygiene most frequently were dry matter and compost temperature. Based on our results, CBPs reduce the prevalence of hock lesions. Cow hygiene was affected by various factors, and therefore good management of CBPs is required for good cow hygiene.