Skin disease in sheep (Ovis aries): A retrospective report of 299 cases at a university veterinary medical teaching hospital (1986-2020).

Abstract

Background: Skin diseases in sheep are important animal health and production problems, especially in wool-producing sheep.

Hypothesis/objectives: To document the type, signalment, associations and prevalence of skin disease in a referral hospital population.

Animals: Case population at a university veterinary medical teaching hospital.

Materials and methods: Retrospective study by searching computerised medical records of sheep examined between 1 January 1986 and 1 January 2021.

Keywords: 'alopecia, Arcanobacterium pyogenes, Corynebacterium, Demodex, dermatitis, Dermatophilus, dermatophyte, ectoparasite, examination, fibre damage, foot rot, fungus, interdigital necrobacillosis, itching, lice, Malassezia, melanoma, mite, pruritus, rubbing, scabies, skin, SCC, squamous cell carcinoma, Staphylococcus, Trueperella pyogenes, wool break, wool loss'.

Results: Two thousand and two records, totalling 11,799 sheep, had the age, breed and sex reported. Older sheep were more likely to present with skin disease (p < 0.0001; standard deviation 36.6 ± 1.15 confidence interval). The American Merino, East Friesian, Rambouillet, Suffolk and Shetland breeds were at higher risk of developing skin disease (p < 0.0001). Males, whether rams or wethers, were more likely to present with skin disease than ewes (p = 0.0019). Owing to the lack of dermatological examination reported, the four largest flocks (a total of 7,892 sheep) were excluded from disease analysis. Of the remaining 3,907 sheep, 299 (7.6%) had skin disease recorded. The most common diagnoses made were pododermatitis, bacterial abscesses, squamous cell carcinoma and myiasis. Fifty-five of 299 sheep were presented primarily for nonskin disease.

Conclusions and clinical relevance: Clinicians should include a dermatological examination in sheep regardless of the reason for presentation.