Effects of hydroxypropyl starch on intestinal health and transcriptome of geese

In recent years, gout resulting from uric acid metabolism disorders has led to significant economic losses in goose production. The intestine is a vital organ crucial for uric acid metabolism. Hydroxypropyl starch (HPS) is a resistant starch modified from natural starch, which can enhance intestinal health as a dietary ingredient fiber. In this study, 240 30-day-old Yangzhou geese with similar body weights were divided into three groups: The control group (CG) received a basal diet + 5% corn starch; the hydroxypropyl starch group (HPS) and the sodium urate group (SU) were given a basal diet + 5% hydroxypropyl starch. The experiment lasted for 21 days, and the SU group was administered 30 mg of sodium urate per day during the last 4 days of the study. The results indicated that the level of uric acid in the HPS group was 56.6 µmol/L, significantly lower than that in the CG group (70.8 µmol/L) and the SU group (129.7 µmol/L). The morphological findings revealed that the ileum of the CG group and the SU group exhibited varying degrees of damage, while the HPS group maintained complete structure. The villus height and the ratio of villus height to crypt depth in the HPS group were significantly higher compared to those in the CG and SU groups, while the crypt depth was significantly lower than that in the SU group. A total of 1462 differentially expressed genes (DEGs) were identified at the transcriptome level. GO and KEGG functional enrichment analyses indicated that the DEGs were significantly enriched in the Brush border membrane, Brush border, PPAR signaling pathway, PI3K-Akt signaling pathway, and other related processes. Subsequent analysis revealed that HPS up-regulated the expression of genes associated with intestinal function (such as SLC5A12 and SLC5A8), structure (including NR5A2, IPMK), and uric acid metabolism (PDZK1). The accuracy and reliability of transcriptome sequencing data were confirmed by RT-qPCR. In this study, we systematically demonstrated that HPS can improve intestinal morphology and reduce serum uric acid levels, emphasizing its potential as a dietary supplement for geese.