Efficacy of 2-Hydroxy-4-(methylthio) Butanoic Acid (Alimet~(R) Feed Supplement) as a Source of L-Methionine for Ruminants

摘要

Alimet~(R) Feed Supplement (2-hydioxy-4-(methylthio)butanoic acid, HMTBA) is commonly used as a source of supplemental L-methionine (L-met) in diets for poultry and swine. Numerous studies have been done to investigate the metabolism of this L-met source in poultry and these have recently been reviewed (Dibner, 2003). The goal of this report is to review the available data on metabolism and use of HMTBA by ruminants, Alimet supplementation improves performance of dairy (Rode et al., 1997; Harrison etal., 2001) and beef (Rodriguez et al., 2002) cattle fed methionine deficient diets. These data will be presented. Although the performance improvement in these studies is clearly a response to supplemental methionine, Alimet metabolism differs from thatof other commercially available methionine sources for ruminants, protected DL-methionine (protected DL-met). This has led to some confusion in the industry about the mechanism of action of Alimet and the appropriate way to assess its effect on the animal. These metabolic differences will be discussed.