This study was designed to investigate the effects of dietary structure on urea transporter-B (UT-B) expression in digestive system of goats. A total of 18 Inner Mongolia white cashmere goats with the same father were divided into 6 groups with 3 replicates per group and 1 goat per replicate. After 45 days, one goat was selected and euthanized in each group in a completely randomized design, and samples were taken for Western Blot for UT-B and for evaluation of the relative quantity of the 34 ku UT-B. The results showed as follows: the 30 to 55 ku UT-B were shown in all samples and all of them contained 34 ku UT-B; the expression of 34 ku UT-B in forestomach (rumen, reticulum and omasum), ileum, blind sac of cecum and kidney were improved by high dietary protein level, but extrusion corn lowered the UT-B expression in the ileum and liver. Among organizations, the order of the intension for 34 ku UT-B is liver, abomasum, reticulum, ventral rumen, dorsal rumen, parotid salivary gland, omasum, duodenum, cecum, blind sac of cecum, ileum and kidney. Therefore, the expression of UT-B in the digestive system of goats can be adjusted by the variation of dietary structure, and it can provide a far-reaching foundation of research in urea cycle and nitrogen metabolism.［Chinese Journal of Animal Nutrition, 2011, 23（5）：875 -880］
DU Jianwen，SUN Haizhou，ZHAO Cunfa，LI Shengli，SONG Lixia
. Effects of Dietary Structure on Urea Transporter-B Expression in Digestive System of Goats[J]. Chinese Journal of Animal Nutrition, 2011
, 23(05)
: 875
-880
.
DOI: 10.3969/j.issn.1006-267x.2011.05.024
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