This study profiled the rumen (RM), small intestine (SI), and large intestine (LI) of 24 samples collected from eight 6-month-old Qianqiu goats (body weight 28.40 ± 1.80 kg), with the samples equally divided into three groups. A combination of methods was used, including 16S rRNA sequencing, untargeted liquid chromatography–mass spectrometry (LC-MS) metabolomics, Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, and weighted gene co-expression network analysis-based module detection (WGCNA) with network integration. An uncommon composition of organisms dominated the SI: the hydrogenotrophic methanogens Methanobrevibacter (SI 24.51%; RM 1.92%; LI 2.19%) and Methanosphaera (SI 0.43%; RM 0.02%; LI 0.02%), together with the acetogen Acetitomaculum (SI 1.58%; RM 0.34%; LI 0.11%), were markedly more abundant compared to the RM or LI. Correlation and pathway analyses indicated that Methanobrevibacter was positively correlated with a steroid-type lipid metabolite (r = 0.52, p < 0.05) and with bile-acid-related metabolites. Acetitomaculum was positively correlated with several metabolites: 4-Hydroxyphenyl 4-hydroxybenzoate (r = 0.79, p < 0.05), 2-Aminoethyl dihydrogen phosphate (r = 0.76, p < 0.05), 1-Myristoyl-2-stearoyl-sn-glycero-3-phosphocholine (r = 0.76, p < 0.05), and 1,2-Dioleoyl-sn-Glycero-3-Phosphocholine (r = 0.74, p < 0.05). Together, these data define a small-intestinal microbial–metabolite module in Qianqiu goats characterized by elevated abundances of specific methanogens and acetogens in the SI. Specific positive correlations were identified between these taxa and metabolites associated with lipids and bile acids.

The effective growth and maturation of porcine oocytes in vitro are critical for advancing reproductive biotechnologies. In this study, we explored low-temperature plasma (LTP) treatment as a redox modulation strategy to enhance the survival and maturation of denuded porcine oocytes during in vitro primary culture in order to improve animal cellular health through innovative interventions. Freshly isolated oocytes were exposed to plasma treatment for different lengths of time and subsequently cultured under established in vitro conditions. Morphological and redox-related analyses showed that LTP treatment was associated with increased oocyte diameter, a higher first polar body extrusion rate, mitochondrial membrane potential changes, and altered intracellular and extracellular redox-related parameters. These beneficial effects exhibited a distinct time-dependent dose–response pattern. Furthermore, Western blot analysis showed altered expression of the EGFR/ERK signaling cascade and proteins such as Nrf2, suggesting that LTP treatment might participate in the regulation of maturation-related responses in porcine oocytes cultured in vitro by inducing redox-associated changes, along with alterations in EGFR/ERK-related signaling, Nrf2 expression, and molecules involved in maturation and apoptosis. Collectively, these findings highlight the positive role of LTP in supporting porcine oocyte maturation during in vitro primary culture and provide a promising approach for optimizing the in vitro primary culture of porcine oocytes.