Todayโs path rounds are on ๐ฐ๐ก๐ข๐ญ๐ ๐ฆ๐ฎ๐ฌ๐๐ฅ๐ ๐๐ข๐ฌ๐๐๐ฌ๐!
๐๐ก๐๐ญ ๐ข๐ฌ ๐ข๐ญ?
๐๐ก๐ข๐ญ๐ ๐ฆ๐ฎ๐ฌ๐๐ฅ๐ ๐๐ข๐ฌ๐๐๐ฌ๐ is basically as the name suggests, a disease of the muscle that turns it white instead of its normal red colour. This disease is associated with nutritional problems!
๐๐ก๐จ ๐ ๐๐ญ๐ฌ ๐ข๐ญ?
We most commonly see this disease in young animals like calves, lambs and foals, however any species can get this.
๐๐ก๐๐ญ ๐๐๐ฎ๐ฌ๐๐ฌ ๐ข๐ญ?
White muscle disease can be caused by two nutritional issues: ๐ฌ๐๐ฅ๐๐ง๐ข๐ฎ๐ฆ ๐๐๐๐ข๐๐ข๐๐ง๐๐ฒ or ๐ฏ๐ข๐ญ๐๐ฆ๐ข๐ง ๐ ๐๐๐๐ข๐๐ข๐๐ง๐๐ฒ. In mammals, we most commonly associate this condition with selenium deficiency. Both of these nutrients are ๐๐ง๐ญ๐ข๐จ๐ฑ๐ข๐๐๐ง๐ญ๐ฌ, meaning they bind to and neutralize dangerous oxygen-derived chemicals that can damage tissues. When these nutrients are inadequate, the ๐๐ซ๐๐ ๐ซ๐๐๐ข๐๐๐ฅ๐ฌ cause damage to the muscular cell membranes, leading to ๐ง๐๐๐ซ๐จ๐ฌ๐ข๐ฌ (cell death). Necrotic tissues commonly undergo ๐ฆ๐ข๐ง๐๐ซ๐๐ฅ๐ข๐ณ๐๐ญ๐ข๐จ๐ง, where calcium is deposited in the area, which leads to the muscle turning white!
๐๐ก๐ฒ ๐ข๐ฌ ๐ญ๐ก๐ข๐ฌ ๐ ๐ฉ๐ซ๐จ๐๐ฅ๐๐ฆ?
Obviously, muscle that is dead or dying doesnโt function as effectively as a normal, healthy muscle. Because this disease can affect any muscle in the body, the presenting symptoms can be quite variable! Some animals have difficulty eating due to weakening of the muscles in the tongue, while others may have lameness or strange movement due to weakness of the limb muscles. The most severe presentation comes from necrosis of the heart muscle, leading to heart failure.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐๐ข๐๐ ๐ง๐จ๐ฌ๐๐?
Diagnosis in the live animal usually involves measuring the concentration of selenium or vitamin E in the blood. However, the easiest method of diagnosis is seeing the white, calcified muscle from a necropsy specimen under the microscope!
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐ญ๐ซ๐๐๐ญ๐๐? ๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐ฉ๐ซ๐๐ฏ๐๐ง๐ญ๐๐?
Treatment and prevention of this disease are the same: injecting selenium and vitamin E. In affected animals, this restores the antioxidant capacity, and allows the muscle to begin healing. As a preventative, producers with known issues may give all of their young animals this injection to boost their antioxidants before it becomes a problem!
๐๐ก๐จ๐ญ๐จ๐ฌ
1-4) White muscle in the heart from selenium deficiency.
5) What this disease looks like under the microscope! The normal muscle is bright pink with striping. In the middle, you can see muscle with purple calcium covering it.
๐๐จ๐ฎ๐ซ๐๐๐ฌ
Maxie, G. Jubb, Kennedy and Palmerโs Pathology of Domestic Animals, Volume 1. Sixth Edition.
Photos 1, 5 ยฉ University of Calgary Diagnostic Services Unit.
Photos 2-4 Noahโs Arkive contributors Rimoldi, Luginbuhl, Anderson licensed under CC BY-SA 4.0.
