The integrated analysis of digestive physiology and gastrointestinal microbiota structure in Changle goose

Changle goose in Fujian, China is a rare genetic resource and in urgent need to be protected. Understanding the characteristics of digestive physiol-ogy and spatial variation of gastrointestinal microbiota is crucial for developing nutritional intervention strate-gies to improve intestinal health and production perfor-mance of goose. Hence, histomorphological assay was used for observing development status of proventriculus, jejunum, and cecum in 70-day-old Changle geese, whereas digesta from 6 alimentary canal locations (crop, proventriculus, gizzard, jejunum, cecum, and rectum) were collected for 16S rRNA gene sequencing and short chain fatty acids (SCFAs) quantitative analysis. The histomorphological observation indicated that the jeju-num and cecum of Changle goose were well developed. The alpha diversity analysis revealed that, except rec-tum, microbiota in other noncecum sections were in high diversity as cecum. The Nonmetric MultiDimensional Scaling (NMDS) analysis showed that microbial community of proventriculus, gizzard, and jejunum formed a cluster, which distinctly discrete with the microbiota of the other gastrointestinal locations. Addi-tionally, the proportions of Proteobacteria, Bacteroi-dota, and Campilobacterota at the phylum level and Lactobacillus, Streptococcus, Helicobacter, and Subdoli-granulum at the genus level exhibited tremendous alter-nations among different gastrointestinal locations. The characteristic bacterial composition in each section was further disclosed by analyzing the core and feature Amplicon Sequence Variants (ASVs) and SCFAs pat-tern. Importantly, 7 body-weight-associated ASVs and 2 cecum-development-related ASVs were identified via correlation analysis. In a whole, our findings provided the first insights into the specialized digestive physiology of Changle geese and distinctive regional distribution of gastrointestinal microbiota, which laid the important foundation for improving growth performance through microbiota manipulation in geese.