Todayโs path rounds are on ๐๐จ๐ฅ๐ฅ๐๐ ๐๐ง ๐๐ฒ๐ฌ๐ฉ๐ฅ๐๐ฌ๐ข๐! This falls under a recent request for a โcool derm thingโ 
๐๐ก๐๐ญ ๐ข๐ฌ ๐ข๐ญ?
You may have heard of this condition referred to as ๐๐ก๐ฅ๐๐ซ๐ฌ-๐๐๐ง๐ฅ๐จ๐ฌ ๐ฌ๐ฒ๐ง๐๐ซ๐จ๐ฆ๐ in people. Basically, it is a condition where ๐๐จ๐ฅ๐ฅ๐๐ ๐๐ง, the major structural protein found in the skin and joints has an abnormality in the shape or size of its fibers, preventing them from linking together properly to provide strength to the skin.
๐๐ก๐จ ๐ ๐๐ญ๐ฌ ๐ข๐ญ?
So far, this condition has been described in humans, cattle, sheep, horses, dogs, cats, mink and rabbits. But it is entirely possible that other species have this condition!
๐๐ก๐๐ญ ๐๐๐ฎ๐ฌ๐๐ฌ ๐ข๐ญ?
This condition is hereditary, meaning that it is passed down generation to generation. The exact genetic cause varies between species, but the ultimate result is abnormal collagen.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐๐ข๐๐ ๐ง๐จ๐ฌ๐๐?
These conditions can be diagnosed based on clinical suspicion, meaning that the veterinarian can do a thorough exam of the animal and come to a diagnosis based on the most likely cause. The clinical signs can vary somewhat between species, but are typically characterized by very stretchy skin that is extremely fragile and easy to tear. Affected animals may also have joint laxity or hyperextendability, due to the collagen maintaining the normal range of motion of the joint being too stretchy.
In cattle and sheep, this condition is called ๐๐๐ซ๐ฆ๐๐ญ๐จ๐ฌ๐ฉ๐๐ซ๐๐ฑ๐ข๐ฌ, which means โtorn skinโ. Typically, this disease is characterized by thick skin that tears easily, and sometimes hangs loosely. In sheep, this is often most problematic at shearing, where routine handling may cause large areas of skin to be torn off the body.
In horses, this condition is called ๐ก๐๐ซ๐๐๐ข๐ญ๐๐ซ๐ฒ ๐๐ช๐ฎ๐ข๐ง๐ ๐ซ๐๐ ๐ข๐จ๐ง๐๐ฅ ๐๐๐ซ๐ฆ๐๐ฅ ๐๐ฌ๐ญ๐ก๐๐ง๐ข๐ or HERDA. The genetic mutation that causes this condition has been traced back to Poco Bueno, one of the foundation Quarter Horse sires. Typically, clinical signs do not develop until 6-12 months of age, and are characterized by frequent skin wounds. Once the horse begins training under saddle, they will frequently develop large wounds in the saddle area due to friction. Sometimes affected horses will have joint laxity.
In dogs and cats, this condition is called ๐๐ฎ๐ญ๐๐ง๐๐จ๐ฎ๐ฌ ๐๐ฌ๐ญ๐ก๐๐ง๐ข๐. Dogs typically have the easily torn and stretchy skin that occasionally hangs loosely off the body. Occasionally they will have joint laxity as well. Cats have similarly fragile and stretchy skin, but there have not been any cases with joint laxity reported.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐ญ๐ซ๐๐๐ญ๐๐?
Unfortunately, there is no treatment for this condition. Animals are often euthanized because their quality of life is extremely poorโฆ any time they rub up against something or touch something they are at risk of tearing off large sections of skin. Sometimes animals can be managed if they are mildly affected by focusing on wound prevention and diet supplementation to try and boost collagen production.
๐๐ก๐จ๐ญ๐จ๐ฌ
1 and 2) A stretchy dog with cutaneous asthenia.
3 and 4) Stretchy kitties!
5) A horse with HERDA showing the stretchiness of the skin.6) Resulting scarring in a horse with HERDA.
7) Joint laxity in a horse with HERDA.
๐๐จ๐ฎ๐ซ๐๐๐ฌ
Hansen, N., Foster, S.F., Burrows, A.K. Cutaneous asthenia (Ehlers-Danlos like syndrome) of Burmese Cats. Journal of Feline Medicine and Surgery 2015 17(11).
Maxie, G. Jubb, Kennedy and Palmerโs Pathology of Domestic Animals, Volume 1. Sixth Edition.
Rashmir-Raven, A.M, Spier, S.J. Hereditary equine regional dermal asthenia (HERDA) in Quarter Horses: A review of clinical signs, genetics and research. Equine Veterinary Education 2015 27(11).
Photos 1-2 courtesy of Wikimedia Commons.
Photos 3-4 courtesy of Hansen et al.
Photos 5-7 courtesy of Rashmir-Raven et al.
