Studies on methionine derivatives as possible sources of protected methionine in ruminant rations.

Abstract

AbstractN‐Oleoyl‐D,L‐methionine, D,L‐methionine ethyl ester HCI and the methyl ester of methionine hydroxy analogue were examined for their ability to produce methyl mercaptan in the rumen of sheep. Results indicated that all derivatives were more stable than methionine. The derivatives were then examined for their ability, when fed in the diet, to increase the plasma methionine concentration of sheep. Methionine ethyl ester caused a marked rise. Further results suggested that while some of the methionine ester escaped ruminal degradation, it also passed through the rumen wall. The compound was found to be rapidly hydrolysed in the liver to yield methionine. The effects of the other derivatives tested on plasma methionine concentrations were small.