# Hock Lesions, Cow Hygiene, and Compost Quality in Compost-Bedded Pack Barns in Germany

## TL;DR

This study examines hock lesions and cow hygiene in compost-bedded barns in Germany, finding lower hock lesion rates and comparable or better hygiene than conventional systems.

## Contribution

The study provides empirical evidence on hock lesion prevalence and cow hygiene in compost-bedded pack barns in Germany.

## Key findings

- Hock lesion prevalence was 1.0% in cold seasons and 3.9% in warm seasons, lower than conventional systems.
- Udder hygiene was best, with 15% poor hygiene in cold seasons and 7.5% in warm seasons.
- Compost dry matter and temperature most affected cow hygiene.

## Abstract

The prevalence of hock lesions and cow hygiene are indicators of housing system quality in dairy cattle. Compost-bedded pack barns (CBPs) have been shown to benefit the health and welfare of cows; however, further studies are needed to substantiate those findings. The present study evaluated various factors affecting cow hygiene and the prevalence of hock lesions in CBPs in southern Germany. The prevalence of hock lesions was 1.0% in the cold season and 3.9% in the warm season, which were lower than the results of previous studies in conventional housing systems. Cow hygiene was comparable to or better than that of conventional housing systems. Compost variables, compost quality, housing conditions and season affected cow hygiene.

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.