Updated: Apr 18
"Spring has Sprung as Hair is Flung" - Rewind Equine
All that shedding hair can be comforting to some as we know that Spring is here, or terribly annoying as it sticks to everything, and I mean everything (seriously, don't even think about lip balm). It lengthens our grooming time, and wreaks havoc on our laundry machines but what else can it teach us about the health of our horses?
Shedding and hair growth are actually very complex physiological processes that can tell us a lot about the health of our animals. This process is regulated by a small gland in the brain called the pineal gland. Stimulus from the environment and exposure to daylight is relayed to the pineal gland, through the retina in the eye, and sets off a host of chemical reactions.
Melatonin is a powerful hormone stimulated by light exposure, that regulates our circadian rhythms (sleep-wake cycles). It is at its lowest concentrations during daylight hours and highest when it’s dark. It communicates vital information like what season it is and whether or not to grow or shed hair. It also prods the reproductive systems into action. When the daylight increases, melatonin production decreases and then it's bye-bye winter coat!
So what happens when things don't exactly go as planned?
The Slow Shedder
Slow shedding can be a sign of Cushing's disease or PPID (pituitary pars intermedia dysfunction), an endocrine disorder that affects the neural pathways in the brain, specifically from the hypothalamus and pituitary glands for hormone regulation. The inability of the brain to control the proper hormone production affects many bodily processes and is considered quite common in older horses. If left unchecked, this condition suppresses the immune system, throws blood sugars out of whack and causes inflammation that can lead to laminitis.
The Patchy Shedder
Patchy shedding can be caused by a host of things... Could be something simple, such as environment and temperature, or it can be caused by an infectious skin fungus, such as ringworm. It could be the result of scratching an itch or an allergic reaction caused by tiny biting insects like mites. Internal parasite such as onchocera, can also cause immune response reactions.
Onchocerciasis is an infestation by a roundworm that lives in the nuchal ligament along the top of the neck. When the larvae hatch, they travel to the muscles of the neck and skin causing blistery, crusty bumps that cause severe itching and can lead to self-inflicted hair loss due to the excessive scratching. If you'd like to learn more there, here is a great article with more info on onchocerciasis: https://wagwalking.com/horse/condition/onchocerciasis
A high protein diet can lead to a protein build-up and also cause hair loss. Abnormal or inconsistent eating habits, increased stressors, poor gut health, or underlying health conditions may result in protein malnutrition. When this happens, the body will help save protein by shifting growing hairs into the resting phase.
Signs of Protein Buildup:
Hair feels straw-like and stiff.
Hair is dry, lifeless, and brittle.
Dull; it no longer has that natural shine/luster.
More tangles, strands, or hair fall.
What ever the cause may be, when in doubt, check with your Veterinarian. The best medicine is an ounce of prevention. Regular health check ups and bodywork can make all the difference!