Incidence of recurrent seasonal pruritus (‘sweet itch’) in British and German shire horses.

This research paper explores the prevalence of a type of seasonal pruritus, commonly known as ‘sweet itch’, in British and German shire horses.

Background Information

• In both the British and German context, there was a common belief that the incidence of ‘sweet itch’ was high among shire horses.
• Prior to this study, there was a lack of published data that supported these claims, particularly for British horses.
• The researchers highlighted a previous survey by the British Equine Veterinary Association (BEVA) in 1965, which suggested that around 1.5% of heavy horses experience skin conditions, with 0.23% specifically identified as ‘sweet itch’.
• This study aimed at providing a more accurate approximation of ‘sweet itch’ prevalence in British and German shire horses.

Data Collection

• Data was gathered through questionnaires sent out to members of the British Shire Horse Society and the German Shire Horse Society.
• The questionnaire sought information about the number of horses owned by respondents, the number of horses affected by ‘sweet itch’, the age of onset of the disease, and whether any related animals were known to be affected.
• Responses were received from 184 British owners of 1088 shire and shire crosses and 43 German members with information about 77 horses.

Findings

• The study found that the number of horses suffering from ‘sweet itch’ in the surveyed populations was 126 in Britain and 29 in Germany, representing a prevalence of 11.6% and 37.7% respectively.
• The difference in the prevalence of ‘sweet itch’ in the two countries was determined to be statistically significant.
• The peak age of onset for ‘sweet itch’ was two years for British horses and one year for German horses.
• A familial incidence was reported by 36.8% of British owners and 34.5% of German horses were known to have affected relatives.

Conclusions and Limitations

• The study validates the belief of a high incidence of ‘sweet itch’ in German shire horses, with a rate three times higher than that of British shire horses.
• However, the researchers question the accuracy of these results due to a low response rate from British horse owners which could lead to potential bias.
• The prevalence of ‘sweet itch’ in British shire horses, as derived from the study, is a considerable increase from the figures reported in the previous BEVA survey.