Fine-tuning a cow

Gary Sliworsky

Bang! Sputter! Miss! When your car’s carburetor gets too much or too little of gas or oxygen, problems can arise. The engine of the cow works the same way. The rumen or cow engine can be delicately fine-tuned to adjust performance and make happier cows. Following are some tips from Barry Potter, Livestock Specialist with OMAF.
The first adjustment necessary is to check the fuel going into the engine. Analyzing the feed value of your forages will assist in balancing the ingredients you put into the cow. Getting the right test is the first step in any successful ration tune up.
Many producers today are feeding high octane forages to their cows. By that we mean early cut alfalfa with low percentages of effective fiber. As well these feeds produce a lot of rapidly available nitrogen in the rumen. This excess nitrogen can create acidosis problems. Extra energy is needed to excrete the nitrogen. As well, displaced abomasums occur from a lack of effective fiber. Matching the carbohydrate supply (concentrates) with protein supply (forages and supplements) acts like a carburetor adjustment for oxygen and gas ratios.
Carbohydrate balance in the diet has an important impact on milk production because it affects the amount and ratio of volatile fatty aids produced in the rumen. Volatile fatty acids (VFAs) affect the metabolism and partitioning of nutrients.
What do we do when we have excellent alfalfa haylage? Possibly changing the grain we are feeding can help with rumen balance. Rapidly available nitrogen needs a supply of rapidly available carbohydrates in order to be used effectively. Three factors can influence carbohydrate availability: the source, the particle size, and the treatment of the grain.
For example, wheat degrades quicker than barley, which degrades quicker than corn. High moisture grains degrade quicker than dry grains. Processed grains break down quicker than whole grains. Therefore, if you have a very early cut haylage, you may assist the rumen by adding wheat to your ration. Using wheat in a TMR is very safe. Using it in a grain mix will still require limiting the percent to less than 25% of the mix.
Grinding your grain will also assist with this. Ten years ago the message was to have as coarse a grain mix as possible. Now with TMRs and the inability of cows to discriminate against fines, grinding the concentrates makes more sense.
Along with feeding the rumen properly remains the necessity of matching your protein supplement with your feeds. A diet high in soluble protein such as alfalfa haylage will not benefit from inclusion of a highly soluble protein supplement such as whole peas. And maybe those beans will have to be roasted. Or add a high bypass protein such as corn gluten meal or fishmeal to the diet.
Putting the pedal to the metal and pushing our production levels is critical to economic viability. But just like taking your car in for a fall tune up, now is the time to fine-tune your ration to meet your production goals.
Dates to Remember
Oct.19 - RRFA Annual Meeting, Dinner & Dance, Devlin Hall