WASHINGTON – Agricultural Research Service (ARS) animal scientist Bret Taylor, who works at the ARS US Sheep Experiment Station (USSES) near Dubois, Idaho, said a more cost-effective, longer-lasting selenium supplement for livestock may soon be available, which is good news for producers and livestock.
In order to stay healthy, all animals (including humans) need selenium, which is a trace mineral and component of antioxidants. Not enough selenium in sheep reduces conception rates, increases neonatal mortality and sometimes causes white muscle disease – also called nutritional muscular dystrophy. Selenium deficiency in sheep and cattle costs livestock producers an estimated $545 million in losses per year plus it affects livestock in more than 35 states where regions are deficient in the mineral.
ARS writer Sandra Avant explained that Taylor along with researchers at North Dakota State Univ., studied the effects of a milling co-product, derived from selenium-rich wheat harvested in South Dakota, on ewes and their lambs.
The natural co-product was added by the scientists to diets fed to a group of ewes during their final 40 to 50 days of pregnancy and to another group during the first 19 days of lactation. Pregnant sheep passed the supplemental selenium along to their fetuses; lactating ewes delivered it to offspring through their milk. Both groups maintained an adequate selenium status six to 10 times longer than sheep receiving sodium selenite -- which is the most commonly used inorganic form of selenium, ARS relays.
Taylor said livestock producers can eliminate the cost of delivering selenium supplements to sheep in hard-to-reach regions, especially in the West where selenium in some soils is lacking or unavailable for absorption by vegetation that animals eat, by using this feeding strategy.
Before being released to graze selenium-deficient range, sheep can be fed the selenium co-product, which will provide enough to meet their selenium requirement, Taylor added. Animals using this co-product will not need additional supplements until they return for lambing the following year, he concluded.