Ruminants obtain nutrients from microbial fermentation of plant material, primarily in their rumen, a multilayered forestomach. How the different layers of the rumen wall respond to diet and influence microbial fermentation, and how these process are regulated, is not well understood. Gene expression correlation networks were constructed from full thickness rumen wall transcriptomes of 24 sheep...

Whether dietary non-fiber carbohydrate (NFC), a rapid fermentable substance, affects immune homeostasis of rumen through the modulation of interactions of ruminal microbiota and epithelial toll-like receptors (TLRs) remains unclear. A combination of 16S rRNA amplicon sequencing and quantitative PCRs was applied to study the synergetic responses of ruminal microbiota and epithelial TLRs to the d...

STEVENS, CHARLES E. Transport of sodium and chloride by the isolated rumen epithelium. Am. J. Physiol. 206(5) : 1099-I 105. I g64.-Transepithelial electrical potential, short-circuit current, and resistance measurements were made under different conditions of tissue collection and maintenance. The collection procedure greatly affected tissue resistance and, since the magnitude of the current wa...

BACKGROUND Diet-derived short-chain fatty acids (SCFAs) in the rumen have broad effects on the health and growth of ruminants. The microbe-G-protein-coupled receptor (GPR) and microbe-histone deacetylase (HDAC) axes might be the major pathway mediating these effects. Here, an integrated approach of transcriptome sequencing and 16S rRNA gene sequencing was applied to investigate the synergetic r...

The rumen of the sheep is lined with a stratifiedsquamous epithelium, through which are absorbed short-chain fatty acids, ammonia and probably other products of the microbial degradation of foodstuffs in the rumen. The finding that this tissue can metabolize most of the short-chain fatty acids occurring in the rumen (Pennington, 1952; Annison & Pennington, 1954) and possesses a capacity for ket...

STEVENS, C. E., AND B. K. STETTLER. Factors affecting the transport of volatile fatty acids across rumen epithelium. Am. J. Physiol. 2 IO(~) : 365-372. I g66.-Isolated, short-circuited rumen epithelium was used to study the effects of pH, concentration gradient, imidazole vs. bicarbonate-buffer systems, and fatty acid metabolism on the transport of volatile fa tty acid. Transport of acetate a n...

1. In liver, rumen epithelium and kidney cortex of the sheep, a dehydrogenase active against dl-3-hydroxybutyrate occurred in both the cytosol and particulate fractions of the tissues. In brain, heart, skeletal and smooth muscles, the enzyme occurred only in the particulate fraction. 2. Enzyme activity in the cytoplasmic fraction of liver and rumen epithelium was similar with either d(-)-3-hydr...

1. The rumen adapts to increased food intake by the hyperplasia of epithelial cells. 2. Volatile fatty acids (VFA) stimulate cell mitosis of sheep ruminal epithelium in vivo. 3. Since VFA generally inhibit cell proliferation in vitro insulin was proposed in this study as the possible mediator of the mitotic stimulation in vivo. 4. Infusions (6 h) of insulin (0.125 U/kg per h) plus glucose (300 ...

The functional organisation of the bovine rumen epithelium has been examined by electron and light microscopy combined with immunocytochemistry in order to define a transport model for this epithelium. Expression of connexin-43, an integral component of gap-junctions, the tight-junction molecules claudin-1 and ZO-1 and the catalytic α-subunit of the Na-K/ATPase were demonstrated by SDS/PAGE and...