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The Qinghai-Tibetan Plateau is a large and elevated plateau (mean elevation 4500 m) in northwestern China, where with a harsh environment for animal survival. Tibetan sheep is an important dominant livestock that inhabit this harsh environment. The objective of this trial was to preliminarily explore and compare the effects of indigenous barley straw (BS) and artificial cultivated oat hay (OH) on growth performance, visceral organ mass and meat quality of Tibetan sheep. Twenty-four Tibetan sheep with initial weights of 15.9±1.92 kg were randomly assigned to two mixed diets containing the same concentrate mixed with BS or OH, and the experiment was carried out in a completely randomized design. The weight of lungs and thymus for OH was greater (P≤0.05) than that of BS, while the weight of other viscera (heart, liver, kidney, epinephros and spleen) had no significant difference (P>0.05) between the two. The weight of the rumen, reticulum and abomasum for OH was 10.31%, 31.22% and 33.44% (P≤0.01) higher than that of BS. The length of the colon in sheep fed OH diet was longer (P≤0.01) than the sheep fed BS diet. The content of Histidine in longissimus dorsi muscle of OH was greater (P≤0.05) than that of BS, while there were no significant (P>0.05) differences between the two for the other individual amino acids (AA), umami AA, essential AA and total AA. It is concluded that the two types of roughage did not affect the growth and slaughter performance, meat quality, but OH is beneficial for the gastrointestinal development for Tibetan sheep.

Summary: RNA granules are membraneless condensates that provide functional compartmentalization within cells. The mechanisms by which RNA granules form are under intense investigation. Here, we characterize the role of mRNAs and proteins in the formation of germ granules in Drosophila. Super-resolution microscopy reveals that the number, size, and distribution of germ granules is precisely controlled. Surprisingly, germ granule mRNAs are not required for the nucleation or the persistence of germ granules but instead control their size and composition. Using an RNAi screen, we determine that RNA regulators, helicases, and mitochondrial proteins regulate germ granule number and size, while the proteins of the endoplasmic reticulum, nuclear pore complex, and cytoskeleton control their distribution. Therefore, the protein-driven formation of Drosophila germ granules is mechanistically distinct from the RNA-dependent condensation observed for other RNA granules such as stress granules and P-bodies.

Hydrogen (H2) is an essential substrate for methanogens to produce methane (CH4), and also influences pathways of volatile fatty acids (VFA) production in the rumen. Dissolved H2 (H2 (aq)) is the form of H2 available to microbes, and dissolved CH4 (CH4 (aq)) is important for indicating methanogens activity. Rumen H2 (aq) concentration has been estimated by assuming equilibrium with headspace gaseous H2 (H2 (g)) concentration using Henry's law, and has also been directly measured in the liquid phase in some in vitro and in vivo experiments. In this in vivo study, H2 (aq) and CH4 (aq) concentration measured directly in rumen fluid and their corresponding concentrations estimated from their gaseous phase concentrations, were compared to investigate the existence of equilibrium between the gas and liquid phases. Twenty-four Tibetan sheep were randomly assigned to two mixed diets containing the same concentrate mixed with oat grass (OG diet) or barley straw (BS diet). Rumen gaseous phase and contents were sampled using rumenocentesis and oral stomach tubing, respectively. Rumen H2 (aq) and CH4 (aq) concentration and VFA profile differed between sheep fed OG and BS diets. Measured H2 (aq) and CH4 (aq) concentration were greater than H2 (aq) and CH4 (aq) concentrations estimated using gas concentrations, indicating lack of equilibrium between gas and liquid phase and supersaturation of H2 and CH4 in rumen fluid. As a consequence, Gibbs energy changes (ΔG) estimated for various metabolic pathways were different when calculated using dissolved gases concentrations directly measured and when using dissolved gases concentrations assuming equilibrium with the gaseous phase. Dissolved CH4, but not CH4 (g), was positively correlated with H2 (aq). Both H2 (aq) and H2 (g) concentrations were positively correlated with the molar percentage of butyrate and negatively correlated with the molar percentage of acetate. In summary, rumen fluid was supersaturated with both H2 and CH4, and H2 (aq) was closely associated with the VFA profile and CH4 (aq) concentration. The assumption of equilibrium between dissolved gases and gaseous phase affected ΔG estimation. [ABSTRACT FROM AUTHOR]