Summary: | <i>Dichelobacter nodosus</i> is the causal agent of ovine footrot, a contagious disease of welfare and economic concern worldwide. Damaged feet may be subclinical carriers of <i>D. nodosus</i> and covertly spread infection. Accordingly, we evaluated the risk of misshapen and damaged feet on <i>D. nodosus</i> presence and load in four commercial UK sheep flocks. Foot-level observations and swabs (<i>n</i> = 972) were collected from ewes (<i>n</i> = 85) over 12 months. On average, ewes were sampled three times. Feet were inspected for disease and scored (good/poor) for three hoof conformation traits (sole and heel, wall, and wall overgrowth). Swabs were analysed for presence and load of <i>D. nodosus</i>, and mixed models were constructed. Poor hoof conformation traits were present in 92.5% of foot-level observations. Feet with poor sole and heel conformation were more likely to have higher <i>D. nodosus</i> loads (β = 0.19, 95% CI: 0.04–0.35) than those with good conformation. Furthermore, on feet positive for <i>D. nodosus</i>, wall overgrowth was associated with higher <i>D. nodosus</i> loads (β = 0.27, 95% CI: 0.01–0.52). Feet with aspects of poor conformation covertly harbour <i>D. nodosus</i> and are a source of infection. Flock management should be guided by hoof conformation to reduce disease challenge.
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