Feeding blood meal separately in a supplement or top-dressed on a ration sometimes causes palatability problems, but mixing it into the total ration has avoided this problem. The value of meat meal varies due to the amount of heat applied in drying and the amount of bone and hair contamination. Meat meal has the advantage of containing high amounts of phosphorus and fat. Palatability may be a problem if it is fed separately in a supplement or top-dressed on a ration, but not if it is mixed into the ration. Less research is available on the degradability of fish meal protein, but it appears to be a high bypass protein.
Fish meal is high in essential amino acids and B-vitamins.
Because of its high lysine content and low availability, the price is usually high. Excess oil in fish meal can lead to rancidity, and inadequate drying may allow molding. Compared to corn gluten meal, the value of brewers grains is slightly lower due to its higher fiber content. Brewers grains is high in methionine and low in lysine, but does not need to be fed in conjunction with a high quality protein source. Brewers grains is the most palatable of the high bypass protein sources.