Submitted to: Hoard's Dairyman
Publication Type: Popular Publication
Publication Acceptance Date: August 11, 2006
Publication Date: February 10, 2007
Citation: Broderick, G.A. 2007. We're learning more about protein quality. Hoard's Dairyman. 152(3):101. Technical Abstract: Dietary protein quality is important to lactating dairy cows. The effectiveness of RUP sources vary because of varying content of essential amino acids required by the cow to use as protein building blocks. For dairy cows fed alfalfa and corn silages, plus corn-based concentrate, RUP from fishmeal and canola meal were better than soybean meal, but cottonseed meal was poorer, for producing milk and protein. Utilization of the RUP in soybean proteins is limited by insufficient amounts of Met, as essential amino acid. Supplementation with rumen-protected Met will allow cows to be fed perhaps 2% less CP in dietary DM, without reducing production of milk and milk protein.