The advantage of this technique is that it is relatively rapid and it can be used to estimate protein degradability of individual feedstuffs as well as the total diet. From the foregoing it is clear that our current methodology for measuring the rate and extent of digestion of protein in a feedstuff is far from perfect. Thus, book values for various feedstuffs should be considered as broad approximations rather than absolute values. This is particularly true when you consider that the feed intake of the animal can have a substantial effect on the extent of protein digestion in the rumen. As feed intake increases the average time that a particular feedstuff spends in the rumen decreases.
Less time spent in the rumen means less time for bacteria or protozoa to breakdown the protein.
Conclusions Formulating dairy cattle diets on the basis of soluble, degraded and undegraded protein has been shown to result in increased milk production and more efficient utilization of dietary protein. However, accurate measurement of these protein fractions in various feedstuffs is extremely difficult. Thus, there is still a great deal of uncertainty associated with our ability to predict protein supply to the intestine under practical conditions. Despite the uncertainty associated with the accuracy of the data on extent of ruminal digestion of protein sources, available information can be used in a qualitative sense to formulate diets which will result in more efficient utilization of protein and optimum milk production. References Agricultural Research Council.