Dairy cattle

Estimation of heritability of hoof and leg disorders and their genetic relationships with longevity and feet and leg conformation traits in Holstein Cows

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Abstract

In Japan, approximately 25% of the culling of Holstein cows is due to disease, and more than 30% of these cases are attributable to problems of the feet and legs, making them one of the major health issues in dairy farming. Hoof and leg disorders significantly affect the productivity, welfare, and longevity of cows, resulting in considerable economic losses due to decreased milk yield, increased veterinary costs, and premature culling. Understanding their genetic basis and effects on longevity and hoof and leg conformation traits is important for developing effective breeding strategies to improve hoof health. This study aimed to estimate genetic parameters for hoof and leg disorders and to investigate their genetic relationships with longevity, hoof and leg conformation traits in Holstein cows in Japan.Genetic analysis was conducted using data on hoof and leg disorders collected by the Agricultural Mutual Relief Association, including lactations 1 to 3 of 379,098 Holstein cows since 2004. The disorders analyzed were arthritis, interdigital dermatitis, interdigital phlegmon, digital dermatitis, purulent pododermatitis, white line lesion, and sole ulcer, each defined as a binary trait (0 = affected, 1 = unaffected). Genetic parameters were estimated using a repeatability animal model, and genetic correlations between disorders, stayability, and hoof and leg conformation traits, including rear legs side view, rear legs rear view, foot angle, bone quality, heel depth and locomotion, were estimated using a two-trait linear animal model based on first parity records.The incidence of hoof and legs disorders ranged from 0.5% to 1.5% in first parity, 1.0% to 1.7% in second parity, and 1.3% to 2.6% in third parity, showing a tendency for higher incidence in later parities. Heritability estimates for hoof and leg disorders were generally low, ranging from 0.30% to 1.80%, indicating that environmental factors contribute substantially to the observed variation in these traits. Genetic correlations among disorders ranged from 0.001 to 0.903, suggesting the presence of genetically distinct traits. Favorable genetic correlations between individual disorders and stayability were observed, ranging from moderate to high: 0.63 for arthritis, 0.27 for digital dermatitis, 0.42 for interdigital phlegmon, and 0.36 for sole ulcer. These genetic correlations with stayability suggest that genetic selection could contribute to improved hoof health and extended productive life. In addition, strong positive genetic correlations were estimated between specific disorders and locomotion, including 0.69 for digital dermatitis, 0.73 for interdigital dermatitis, and 0.70 for sole ulcer. In contrast, genetic correlations with hoof and leg conformation traits were low. These results suggest that specific hoof and leg disorders are closely associated with lameness. Overall, these findings indicate that hoof health should be addressed not only through management practices but also as part of breeding goals in dairy cattle improvement programs.

Keywords: 2026

How to Cite:

Kawakami, J., Baba, T., Goto, Y. & Oka, T., (2026) “Estimation of heritability of hoof and leg disorders and their genetic relationships with longevity and feet and leg conformation traits in Holstein Cows”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2286108. doi: https://doi.org/10.31274/wcgalp.23854

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