A cow's rumen contains a diverse group of microorganisms including bacteria, protozoa, fungi, mycoplasmas, bacteriophages and yeast. The microorganisms, or bugs, enable a cow to utilize energy from fibrous sources such as hay. These bugs also manufacture beneficial proteins and vitamins. The cow digests bug byproducts and the bugs themselves to meet its own nutritional requirements. Meeting the nutritional requirements of the cow means you must meet the nutritional requirements of the rumen bugs.

By following a couple of management and nutritional guidelines, you can enhance and maintain the rumen environment.

* Test your forage. Only by knowing the value of the feedstuffs can a diet be formulated to meet the bugs' and cows' needs.
* Change feedstuffs slowly while in transition between two diets. The rumen bugs are very sensitive to changes in their environment. Changing a diet of grass hay to include corn in the cow's ration will lower the pH (acidity) of the rumen. Fiber digesting bugs are sensitive to these changes and will reduce in number and their ability to function. The result will be a decrease in energy production from fiber and an overall deficiency in energy levels until the rumen evolves to better digest corn.
* When supplementing a diet of low quality forage, seek feedstuffs that will enhance the rumen environment to the greatest extent. The rumen bugs digest low-quality forages more slowly than higher quality feedstuffs. Within the rumen, the bugs generally require about 12 percent to 13 percent crude protein. Corn, however, supplies energy to the bugs more quickly than hay. It changes the types of bugs and ultimately reduces the utilization of the low-quality hay. The end result is a condition known as unsynchronized fermentation. Soybean meal degrades at a rate more consistent with low-quality hay. This rate allows for a more synchronized supply of protein and energy to the bugs.