Conference Short Highlights
The American College of Veterinary Internal Medicine recently published several abstracts of their annual meeting related to two endocrine disorders: equine metabolic syndrome (EMS) and equine Cushing’s disease (now called pituitary pars intermedia dysfunction or PPID). EMS is characterized by insulin resistance, regional fat deposits and obesity. PPID is a hormone disorder caused by a small pituitary tumor that causes lethargy, long hair that fails to shed, loss of muscle mass and a potbellied appearance. Most importantly these conditions are also two of the most common causes of laminitis.
Michelson et al. identified gene sequences in Welsh ponies that contribute to the development of EMS. This included genes associated with lipid metabolism and fasting insulin levels. These same genes are associated with obesity in people. Someday this work may lead to a test for horses predisposed to laminitis before the other signs of EMS develop.
From Massey University in New Zealand, researchers determined that up to half of the characteristics associated with EMS can be attributed to the environment rather than individual influences such as breed, sex or genetics; and only a small portion of this environmental influence is explained by diet, exercise and season. They tested for endocrine disrupting chemicals (such as BPA, DDT or phthalates) and found that horses on farms within 30 miles of a chemical disposal site were more likely to have insulin resistance and laminitis. They also documented higher levels of the endocrine disrupting chemicals in the blood of horses with signs…