? cushings

I have a 15 year old (ish) quarter horse mare who is consistently hairy as hell all months of the year. even in the summer she has an extremely thick coat, and its not until august/september that it should be the length they normally get in april. is it worth getting a cushings test just based on hair length although she is not lethargic and shows no other symptoms? or should i just be breaking out the clippers all year round ?

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