Abstract: This study aimed to investigate the regional expression differences of nutrient chemosensing-related genes along the gastrointestinal tract (GIT) of mid-pregnant goats and the effects of nutritional restriction on the expression. Twelve mid-pregnant goats with an average body weight of (23.0±1.0) kg, and age of (2.0±0.3) years were randomly allocated to 2 groups: control group (CG) and nutrient restricted group (RG), each comprising 6 goats. From day 40 of gestation, goats in the CG were fed with a basal diet ad libitum, while those in RG were fed with 60% of the feed intake of CG. All goats were slaughtered on day 96 of gestation, and samples from different GIT were collected to determine the mRNA expression of target genes. The results revealed significant regional expression differences in the target genes: except for SLC38A2 and GPR120, the mRNA of other genes including SGLT1, SGLT3, GLUT2, GLUT5, GPR40, GPR41, GPR43, GPR84, SLC38A1 and SLC7A7 were markedly higher in the small intestine. Nutritional restriction exerted segment-specific regulatory effects: it down-regulated the expression of GLUT5, GPR40 and GPR41 in the duodenum, GPR43 and GPR84 in the jejunum, and SLC38A2 and SLC7A7 in the ileum (P<0.05). Conversely, nutrient restriction up-regulated the expression of SGLT1, GPR40, GPR4, GPR43 and GPR84 in the ileum, and SLC38A1 in the duodenum (P<0.05). In conclusion, nutrient chemosensing-related genes in the GIT of mid-pregnant goats are predominantly expressed in the small intestine. Nutritional restriction appears to maintain systemic homeostasis by enhancing compensatory nutrient absorption in distal intestinal segments, thereby modulating the overall absorption and transport of nutrients along the GIT.
Key words: mid-pregnant goat; gastrointestinal tract; nutrient restriction; monosaccharide transporter; free fatty acid receptor; amino acid transporter
（Acta Laser Biology Sinica, 2026, 35(1): 019-027）