Natural selenium supplement now available for sheep
A new selenium supplement for sheep has been developed. Joshua “Bret” Taylor, a U.S. Department of Agriculture Agricultural Research Service (ARS) animal scientist at the U.S. Sheep Experiment Station near Dubois, ID, teamed up with researchers at North Dakota State University (NDSU) to discover this natural selenium supplement. It’s more cost effective and longer lasting than inorganic forms of selenium.
Taylor collaborated with NDSU scientists to isolate a portion of wheat grain found during milling to produce flour. The organic selenium rich coproduct, a form of selenomethionine, was fed to sheep during the last 40 to 50 days of pregnancy and to ewes during the first 19 days of lactation. The pregnant sheep passed the supplemental selenium to their fetuses, and the lactating ewes delivered it to their offspring through their milk.
As a result, Taylor reported, the long-term selenium status of both groups was boosted for an entire year – six to 10 times longer than the impact seen in animals that received inorganic sodium selenite, a mineral that is the most common form of selenium supplement. The sheep that received the natural selenium supplement didn’t need any additional selenium supplements until they returned for lambing the following year.
Selenium is essential for normal growth in the development of sheep and other animals. Therefore, it is a common supplement in their diets. In sheep, selenium is necessary for reproduction. Selenium deficiency reduces conception rates and increases neonatal mortality, and lambs that do survive suffer from increased disease, reduced weight gain, impaired performance and greater mortality.
Inorganic sodium selenite is inexpensive, but it doesn’t last long, according to Taylor. It absorbs readily in the body but must be provided frequently to animals living in selenium deficient regions.
These findings are especially crucial to large scale producers in selenium deficient regions. Ranchers graze sheep on very extensive land masses, which in many cases can only be reached by horseback. A long-acting organic supplement program would allow producers to reduce the high cost involved in delivering supplements to 1,000 to 2,000 sheep on a weekly basis.
In addition, some land leasing agreements prohibit the use of supplements in specific areas. With the new program, animals could be fed organic selenium rich supplements before being released to graze in these marginally deficient regions.
Many livestock producers are utilizing stockpiled pasture, hay regrowth and warm- or cool-season annuals to extend the grazing season this fall.