Equine Cushing’s Disease, more correctly called Pars Pituitary Intermedia Dysfunction (PPID), is a non-cancerous but progressive enlargement of the pituitary gland in the horse. It is estimated that 20 percent of horses over the age of 15 will develop PPID. Note that Cushing’s Syndrome in humans and dogs (when not due to giving too much steroidal medication) involves an actual tumour of either the pituitary or the adrenal glands, (either benign or malignant), whereas Cushing’s Disease in horses has a different cause.

Horses can develop equine asthma when they’re exposed to airborne organic dust that can found anywhere — in a dirt paddock, on a gravel road, or in an indoor arena. But the most common culprit is dusty, moldy hay. Round bales can be particularly problematic as horses tend to tunnel their muzzles into the bales and inhale dust and mold.

“Most horses have been exposed to the equine herpesvirus,” says Dr. Diego Gomez-Nieto, researcher at the Ontario Veterinary College. Gomez has been part of a research study on the equine herpesvirus (EHV) which discovered the nasal microbiota of infected horses differed significantly from those of a healthy control group. The study came together quickly and was conducted on a horse farm in Ontario that was experiencing an outbreak. The January 2021 research paper explains nasal bacterial microbiota of healthy horses is richer and more diverse than previously reported using culture-based methodology.

Commonly seen in young foals, this infection can be fatal if left untreated. Parasites in the genus Cryptosporidium are an important source of gastrointestinal disease in humans and animals globally. These highly contagious parasites infect the intestine and cause diarrhea and weight loss.