Abstract: This trial was conducted to evaluate the rumen degradability and intestinal digestibility of the fat dry powder coated lysine by nylon bag technique and standard three-step in vitro procedure.Three and 5 months old rumen cannulated Kazakh wethers weighed in average （28.0±2.97）kg body weight were housed in metabolic crate singly.The daily diet was composed of cottonseed hull 200 g，concentrate 500 g，wheat straw 400 to 500 g，and the daily refusals were less than 10%.The results showed that the effective degradability of DM and CP of fat dry powder coated lysine in the rumen were all about 20%，the rumen bypass rate achieved 80% or more.After incubation in the pepsin solution and pancreatin solution for 24 h，the in vitro intestinal digestibility of DM and CP were 63.6% and 98.8%，respectively.In summary，This fat dry powder coated lysine could be used as a novel and effective amino acid supplement in the form of ruminant animals.

Key words:

rumenmso-bidi-font-family: 宋体" lang="EN-US">-protected lysine；effective degradability；intestinal digestibility；rumen；sheep