Boost Gain on Any Pasture
The feed additives Rumensin and Bovatec are now being used for pasture cattle by many livestock operators. In my opinion, these valuable feed additives should be considered for wheat pasture, summer grass pastures and even dry winter pastures for boosting gain. Pasture minerals are a practical way to supply these additives, however pasture supplements can also be used. Even though these feed additives are used primarily in the feedlot, they have outstanding potential for pasture programs if handled properly.

Get Local Information
One source of local information is your feed company representative. They can share their experiences and also lead you to producers that have used or are using these additives.

What Can You Expect?
It is not unlikely to expect an increase in gain of close to eight to 12 percent. If cattle were expected to gain 200 lb on a pasture program, 220 lb of gain would be a goal for calculating the cost and returns expected. Your Elanco representative for Rumensin or the Alpharma Animal Health Company rep for Bovatec are sources of test data for your evaluation.

Mode of Action
Rumensin and Bovatec are ionophore antibiotics. Their action is in the rumen and intestines of cattle. They stimulate gain by shifting the fermentation to a higher amount of energy for the cattle. The effect is even more dramatic for high roughage rations and pasture programs.

These two products work differently. Both will give coccidiosis control, but Rumensin is considered to be more effective for this problem. However, it appears it is easier to get the cattle started on a mineral with Bovatec than one with Rumensin.

There also is a second mode of action. When these ionophores are fed, there is less breakdown of natural feed protein to ammonia in the rumen, therefore more of the protein goes down to the lower gut for true protein digestion. We might expect less washy manure and dirty tailheads of cattle pasturing lush grass and wheat pasture if they are provided an ionophore. At one time, nutritionists proposed a protein sparing action of these additives, but even if possible, adjusting the amount of protein fed is not recommended for cattle on dry, low protein forages and pastures.

Caution About Horses
Here is a caution about these products. Both are toxic to horses if the horses eat a pasture supplement or mineral containing this feed additive. Bovatec is less toxic to horses than Rumensin. But caution should be exercised to prevent horses from eating either a feed supplement, or mineral containing either of these ionophores.

How is Bovatec Supplied?
Feed manufacturers will mix Rumensin and Bovatec with a mixture of minerals to be fed free choice, or it can be added to pasture supplement. We have found it is often custom mixed for each operation. Check with your nutritionist and feed person or representative for their suggestions for a product or formula for your operation. ©

Comments or questions on this or any article by Dr. Sprague can be directed to him at 625 Grandview Avenue, Newton, Kansas, 67114. Or call him at (316) 283-8692.