By: Obioha Durunna, Regional Livestock Specialist, Prince Albert
White muscle disease (WMD) could be the reason some producers have weak calves. The condition is caused by vitamin E and/or selenium (Se) deficiency.
Most producers understand that judging feed, whether grain or forage, by appearance alone doesn’t tell us much about the quality. Eyeballing an animal doesn’t give us much information either. We know that most nutrient deficiencies occur as a result of poor nutritional management.
We understand that Se works with vitamin E to support several important functions including growth, reproduction and immune functions.
Plants are the main direct source of Se and vitamin E to animals given that animals cannot produce these nutrients. Plants take up Se from the soils but create vitamin E. If the soils are deficient in Se, there is a good chance that forages grown on such soils are deficient as well. Vitamin E content of forages is affected by ambient, processing or storage conditions.
It is important to ensure that cows receive enough dietary Se and vitamin E prior to or during periods of high-demand such as pregnancy and lactation. Calves from such cows are not affected by the disease because Se can pass the placental barrier providing adequate Se supply developing fetuses. Further, colostrum contains ample quantity of Se and vitamin E to support calf health.
White muscle disease is diagnosed when skeletal or heart muscle fibres have a whitish or chalky appearance resulting from calcium-salt deposits.
Other clinical signs in calves occur from birth to six weeks of age. Calves may be born dead, are too weak to walk or nurse, and may later die if not treated. Calves may also show signs of respiratory distress if the respiratory muscles are affected, which may lead the owner to treat for pneumonia, which are usually ineffective.
Calves treated for WMD may show no favorable response if the heart muscles were affected. Calves affected by the disease can die suddenly from heart failure.
Affected animals can be treated with injections of sodium selenate in combination with vitamin E. Apart from injectable, some commercial minerals and free-choice salts have been supplemented with Se for easier feeding. Slow-release Se boluses are also available.
In consultations with your vet, simple blood tests on a few of your animals can clarify if the herd is receiving adequate nutrition. It is important to work with your nutritionist and veterinarian to determine what is best for your herd.
For more information please contact your regional livestock specialist or the Agriculture Knowledge Center at 1-866-457-2377.