Timing is everything as they say, and this couldn’t be truer than when talking about equine serological allergy testing. In this short blog we will consider some of the ways to maximise the chances of getting meaningful results.
WHY DOES IT MATTER?
The IgE response is relatively short lived, so it’s important to test when the horse is fully symptomatic
Certain medications can affect the results (usually resulting in lower scores), so check the withdrawal guide before sampling which can be found here
In the case of acute urticarial reactions, ideally wait at least 24hrs after clinical signs appear to allow the circulating IgE levels to increase sufficiently
We offer a free blood storage facility so you can test when the timing is best clinically and then decide at leisure if/when to run the test
Certain allergens will be more prevalent at particular times of year.
The horse’s management and lifestyle can significantly affect their exposure to these allergens so this must be factored in.
WHAT DOES THIS MEAN CLINICALLY?
Example 1 – Cracker the coughing cob
Signalment and history – 6-year-old gelding, chronic cough, worse when stabled over the winter.
Diagnosis after full work-up – Asthma
Ideal time to blood test – Late autumn / winter when stabled long enough to be fully symptomatic but before being given any medication which may affect results.
Interpretation of results – Consider positive results for moulds, dust and storage mites.
Other factors – Cost is an issue so FOC blood storage may be helpful to allow owner time to think/save up. Offering a cost-effective screen (where any clinically relevant positive panels can then be expanded) may also be helpful.
Example 2 – Inca the itchy Irish draft X
Signalment and history – 4-year-old mare, generally itchy, worse in the summer months.
Diagnosis after full work-up – Culicoides hypersensitivity with concurrent atopic dermatitis.
Ideal time to blood test – Summer months after exposure to all types of biting insects and pollens but before being given any medication which may affect results.
Interpretation of results – Consider positive results for biting insects, grass, weed and tree pollens.
Other factors – Initial diagnosis was sweet itch but this was proving very difficult to control. In these cases, it may be worth considering the horse could have multiple allergies
SUMMARY OF ENVIROMENTAL TESTING OPTIONS