At USU we are receiving too many reports of cows not eating or producing as they should. Usually these reports are accompanied by an indication that milk protein % is higher than milk fat %. When we make farm visits or talk to dairy producers on the phone and ask probing questions, we find that these herds are experiencing varying degrees of rumen acidosis.
The most common thing we've found associated with rumen acidosis is alfalfa hay that is too low in ADF and NDF. Relative feed values exceed 200 and protein of the hay is 25 to 27%. While we want high quality alfalfa hay in our dairy rations, we need to be careful that we don't overdo the forage quality aspect. Forage fiber is essential to maintain good rumen health and to maximize rumen microbial efficiency. Occasionally, we find that producers are over processing the TMR, which even further reduces the effectiveness of the fiber that is there. Another common factor associated with rumen acidosis is high levels of barley and other highly fermentable grains in the ration without also including such things as dried beet pulp or other slower fermenting byproduct feeds.
Please don't misunderstand me!! High quality alfalfa can be fed without causing acidosis, but we need to balance the ration effective fiber levels and the ration readily available carbohydrates. This most likely requires the assistance of a well trained nutritionist who understands how to properly formulate rations using high quality forages and to advise producers in the area of feed bunk management.
The following are some guidelines to minimize and prevent rumen acidosis: