Q: I have an 8-year-old Thoroughbred mare that was diagnosed with arytenoid chondritis. The attending vet was shocked that the mare wasn’t panicking due to not being able to breathe–both arytenoid cartilages were almost completely collapsed into her airway. She was treated with daily SMZs (sulfamethoxazole, an antibiotic) for a month, as well as a throat spray of Furacin and DMSO (dimethyl sulfoxide). Now my mare appears to be better, but I can still hear her breathing loudly on a few occasions. However, she doesn’t appear to be struggling for air like she had before she was treated.

She seems most affected when the weather is warm and sunny. I have managed her on 24/7 turnout with access to a run-in shed and in a stall with an attached run with more than 10 hours of daily turnout and see no difference in her preferring one over the other. I was told this condition is a form of "roaring" (laryngeal hemiplegia, a condition involving larynx dysfunction that can severely compromise a horse’s ability to breathe, especially during exercise) but I can’t find any information on this specific problem or what her prognosis is for returning to work in dressage, hunters, or possibly low-level eventing. I have not exercised her since this diagnosis, mostly due to my time restrictions and the winter weather.

What causes arytenoid chondritis, and is it curable? Are there any management changes I can make to keep her comfortable? Would she be able to be a broodmare? Is this condition hereditary?

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A: Arytenoid chondritis