What vitamins and mineral supplements should I provide to sheep?
Answer: The principal minerals of concern for livestock on growing forages are calcium and magnesium. Others to consider are salt, phosphorus, potassium, and sulfur. These minerals are very important for cellular respiration, nervous system development, protein synthesis and metabolism, and reproduction. Mineral supplements are available in many formulations. Because soils differ in mineral content from place to place, it is difficult to recommend a mineral mix that works in all places, although most animal scientists suggest at the very least a mineral mix with a calcium:phosphorus ratio of 2:1. Consider using a loose mineral mix fed free-choice rather than mineral blocks for cattle on lush spring or small grain pasture to avoid grass tetany (hypomagnesemia) and to ensure the animals are getting enough mineral.
Vitamins are important for the formation of catalysts and enzymes that support growth and body maintenance in animals. Green growing plants contain carotene, which is a precursor to vitamin A. If ruminants are on green forage (including green hay) vitamin A should not be deficient. Vitamin A deficiencies occur when ruminants are placed on concentrate feeds, or when fed dry, stored forage during the winter. B vitamins are synthesized by rumen microorganisms so supplementation is not necessary. Vitamin D is synthesized in the skin from exposure to sunlight, so Vitamin E is the only other vitamin of concern that sometimes requires supplementation.
Mineral and vitamin supplementation is very important to maintain herd health, and careful attention must be paid in developing a mineral and vitamin supplementation plan. Keep these things in mind when feeding these supplements to livestock:
1. Keep mineral mixes dry. Wet mineral is unpalatable and is known to lose some of its efficacy when damp.
2. Monitor consumption to make sure it’s always available. Keep the feeders full.
3. Don’t forget that some animals display social dominance. Older, more dominant animals will often eat more than their share of mineral mix. Remedy this by having more than one feeder, separated into different parts of the pasture.
Check with your local Extension agent or veterinarian to determine the mineral and vitamin mixes and recommendations common to your area.
Note: Sheep are very sensitive to copper. If you have sheep on the same farm with cattle and/or goats, it is extremely important to supply them with different mineral mixes, as a mix that is formulated for cattle or goats will likely be lethal for sheep. Loose mineral mixes are better than blocks for sheep and goats.
The ATTRA publication Ruminant Nutrition for Graziers explores this topic in more detail. It provides managers with tools and references to consider biological and climatological variables and make decisions that ensure the ecological and economic viability of a grass-based ruminant livestock operation.
In addition, check out the Livestock section of the ATTRA website, where you’ll find links to a host of additional useful resources.