Potential of infra-red thermography for the detection of summer seasonal recurrent dermatitis (sweet itch) in horses.

The researchers investigated the viability of infrared thermography for early detection of summer seasonal recurrent dermatitis, also known as sweet itch, in horses. They found that affected as well as unaffected sensitive horses displayed warmer temperatures in the potential affected areas than insensitive horses, potentially offering a new method for early detection.

Objective and Method of the Research

• The researchers aimed to probe the utility of infra-red thermography in the early and off-season detection of a condition in horses known as summer seasonal recurrent dermatitis (SSRD), or ‘sweet itch’.
• For their study, they chose a sample group of 19 horses; 13 of those were sensitive to SSRD and six were insensitive.
• The examination was conducted in different seasons- summer and winter- to assess the consistency and accuracy of their method.

Findings from the Research

• The study found that in summer (June, July, and September), six horses that were affected by SSRD and two unaffected yet sensitive mares (including a pony), demonstrated higher temperatures in the areas susceptible to SSRD than the three insensitive mares did.
• Interestingly, even in the winter months (February and March), the research team could distinguish unaffected yet sensitive horses from insensitive ones based on the warm areas in the potential zones affected by SSRD.

Possible Explanation and Implications of the Findings

• The researchers suggested that the warmth in the affected zones could potentially be due to a localized immune response in the horse’s body triggered by the bite of Culicoides imicola, a type of tiny midge commonly linked to SSRD in horses.
• If this is the case, the new method could potentially provide farmers and veterinarians with a useful tool for early detection and prevention of SSRD, which can often be a debilitating condition for horses.
• However, more research is needed to confirm the link between the localized heat reactions detected by the infra-red radiometer and the onset of SSRD in horses, and to refine the use of the technology for this purpose.