Different types of dietary fiber (DF) play important roles in enhancing intestinal health and overall performance in animals. This study investigated the effects of high-DF diets containing different ratios of soluble to insoluble dietary fiber (SDF:IDF) on growth performance, intestinal barrier integrity, microbiota, and metabolite profiles in weaned piglets. The four dietary treatments consisted of a basal diet (CON) and three high-DF diets with SDF:IDF ratios of 0.37, 0.25, and 0.13 (designated HF-0.37, HF-0.25, and HF-0.13, respectively). On days 14 and 28, colonic tumor necrosis factor-α, interleukin-1β, interleukin-6, and interleukin-8 concentrations were higher in the HF-0.37 group than in the CON, HF-0.25, and HF-0.13 groups (P<0.05). Plasma D-lactate and endotoxin levels were lower in the HF-0.25 group compared to the CON group at both time points (P<0.05). Furthermore, colonic zonula occludens 1 expression was upregulated in the HF-0.25 and HF-0.13 groups compared to the CON and HF-0.37 groups on day 14 (P<0.05). At the transcriptional level, all three high-DF diets modulated signaling pathways associated with inflammation and immune responses in the colon. Notably, DF supplementation particularly the HF-0.25 diet upregulated colonic levels of 3-indole butyric acid, nicotinic acid, and 3-methylthiopropylamine on d 14 and reduced certain peptide levels by d 28. These findings indicate that DF supplementation, especially at an SDF:IDF ratio of 0.25, exerts beneficial effects on intestinal integrity in weaned piglets, potentially mediated by alterations in colonic metabolite profiles, whereas HF-0.37 and HF-0.13 exhibited limited impacts on intestinal barrier function.
Planting density is a major limiting factor for maize yield, and breeding for density tolerance has become an urgent issue. The leaf structure of the maize ear leaf is the main factor that restricts planting density and yield components. In this study, a natural population of 201 maize inbred lines was used for genome-wide association analysis, which identified nine SNPs on chromosomes 2, 5, 8, 9, and 10 that were significantly associated with ear leaf type structure. Further verification through qRT-PCR confirmed the association of five candidate genes with these SNPs, with the Zm00001d008651 gene showing significant differential expression in the compact and flat maize inbred lines. Enrichment analysis using the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) databases suggested that this gene is involved in the glycolysis process. An analysis of the basic properties of this gene revealed that it encodes a stable, basic protein consisting of 593 amino acids with some hydrophobic properties. The promoter region contains stress and hormone (abscisic acid (ABA)) related elements. The mutant of this gene increased the first ear leaf angle (eLA) and leaf angle of the first leaf below the first ear (bLA) by 4.96 and 0.97°, respectively, compared with normal inbred lines. Overall, this research sheds light on the regulatory mechanism of ear and leaf structures that influence density tolerance and provides solid foundational work for the development of new varieties.
Inactivated H9N2 vaccines developed with early strains do not protect against recent H9N2 viruses: Call for a change in H9N2 control policy