The invention discloses a method for evaluating the
small intestine digestibility of
amino acid in
rumen undegradable
protein of sheep fattening feed. The method comprises the following steps that
rumen undegradable residues are sealed in
small intestine nylon bags, and then the bags are put in a
hydrochloric acid pepsin solution for cultivation; one cultivated
small intestine nylon bag is placed in the intestinal tract from the duodenal
fistula every 15 min; in 48 h after all the nylon bags are placed in the duodenal
fistula, the small intestine nylon bags are collected from
manure and cryopreserved after chymus residues are washed with running water; after being collected, all the small intestine nylon bags are washed in a full-automatic washing
machine, then dried and weighed, the rest residues are sieved by a 40-mesh
sieve, and all samples are used for analysis of the
amino acid; the small intestine digestibility of the RUP=(the
protein content in the
rumen undegradable residues-the
protein content in the residues digested by the small intestines) / the
protein content in the rumen undegradable residues*100%. The method is accurate and reliable.