- Invited Review - Understanding the functionality of the rumen microbiota: searching for better opportunities for rumen microbial manipulation.

Rumen microbiota play a central role in the digestive process of ruminants. Their remarkable ability to break down complex plant fibers and proteins, converting them into essential organic compounds that provide animals with energy and nutrition. Research on rumen microbiota not only contributes to improving animal production performance and enhancing feed utilization efficiency but also holds the potential to reduce methane emissions and environmental impact. Nevertheless, studies on rumen microbiota face numerous challenges, including complexity, difficulties in cultivation, and obstacles in functional analysis. This review provides an overview of microbial species involved in the degradation of macromolecules, the fermentation processes, and methane production in the rumen, all based on cultivation methods. Additionally, the review introduces the applications, advantages, and limitations of emerging omics technologies such as metagenomics, metatranscriptomics, metaproteomics, and metabolomics, in investigating the functionality of rumen microbiota. Finally, the article offers a forward-looking perspective on the new horizons and technologies in the field of rumen microbiota functional research. These emerging technologies, with continuous refinement and mutual complementation, have deepened our understanding of rumen microbiota functionality, thereby enabling effective manipulation of the rumen microbial community.

Dynamic fecal microenvironment properties enable predictions and understanding of peripartum blood oxidative status and nonesterified fatty acids in dairy cows.

The transition period in dairy cows is a critical stage and peripartum oxidative status, negative energy balance (NEB), and inflammation are highly prevalent. Fecal microbial metabolism is closely associated with blood oxidative status and nonesterified fatty acids (NEFA) levels. Here, we investigated dynamic changes in total oxidative status markers and NEFA in blood, fecal microbiome, and metabolome of 30 dairy cows during transition (-21, -7, +7, +21 d relative to calving). Then the Bayesian network and 9 machine-learning algorithms were applied to dismantle their relationship. Our results show that the oxidative status indicator (OSI) of -21, -7, +7 d was higher than +21 d. The plasma concentration of NEFA peaked on +7 d. For fecal microenvironment, a decline in bacterial α diversity was observed at postpartum and in bacterial interactions at +7 d. Conversely, microbial metabolites involved in carbohydrate, lipid, and energy metabolism increased on +7 d. A correlation analysis revealed that 11 and 10 microbial metabolites contributed to OSI and NEFA variations, respectively (arc strength >0.5). The support vector machine (SVM) radial model showed the highest average predictive accuracy (100% and 88.9% in the test and external data sets) for OSI using 1 metabolite and 3 microbiota. The SVM radial model also showed the highest average diagnostic accuracy (100% and 91% in the test and external data sets) for NEFA with 2 metabolites and 3 microbiota. Our results reveal a relationship between variation in the fecal microenvironment and indicators of oxidative status, NEB, and inflammation, which provide a theoretical basis for the prevention and precise regulation of peripartum oxidative status and NEB.

[Comparison of postoperative deglutition disorder in patients with laryngeal carcinoma after different types of supracricoid partial laryngectomy].

OBJECTIVE: To Evaluate the incidence rates and extents of deglutition disorder in patients with laryngeal carcinoma after different types of supracricoid partial laryngectomy. METHODS: Retrospective analysis of postoperative deglutition disorder in patients with laryngeal carcinoma after different types of supracricoid partial laryngectomy treated in our department from 2005 to 2009. The extents of postoperative deglutition disorder were evaluated using a homemade quantitative score table at 5-20 days postoperation. RESULTS: The score of deglutition disorder was 2.71 ± 0.31 in the supracricoid partial laryngectomy-cricohyoidoepiglottopexy (SCPL-CHEP) operation group and 3.43 ± 0.64 in the supracricoid partial laryngectomy-cricohyoidopexy (SCPL-CHP) group, respectively. The deference was statistically significant between the two groups (P < 0.001). The coefficient between age and score of postoperative deglutition disorder was assessed by Pearson correlation analysis. The coefficient of correlation was 0.947 (P < 0.0001) in the SCPL-CHEP group and 0.907 (P < 0.0001) in the SCPL-CHP group. The incidence rate of deglutition disorder was 1/37 in the SCPL-CHEP group and 7/30 in the SCPL-CHP group, evaluated at 8 weeks postoperation (P = 0.012). The deference between the two groups was significant. CONCLUSIONS: The type of operation procedure is an important factor affecting the occurrence of postoperative deglutition disorder in the patients after supracricoid partial laryngectomy, more serious in the SCPL-CHP group. The severity of postoperative deglutition disorder is more serious along with the increase of patient's age. For the elderly (> 70 years of age) patients with laryngeal carcinoma, the choice of surgical procedure should be more cautious, especially with the SCPL-CHP operation.

[Expression of c-fos and NR2A in auditory cortex of rats experienced tinnitus].

OBJECTIVE: To investigate the plasticity and the role of plasticity in the auditory cortex of rats which experienced tinnitus by screening the plasticity markers immediately early gene c-fos and the NMDA receptor's subtype NR2A. METHODS: Thirty white Wistar rats were randomly distributed into 3 groups: sodium salicylate group (n = 12), physiological saline group (n = 12) and normal control group (n = 6). Tinnitus were induced by salicylate administration and tested by behavioral conditioning studies, and then immunohistochemical staining was used to observe the expression of c-fos and NR2A in the auditory cortex of each group. RESULTS: Behavioral evidence indicated that all of the twelve rats in the sodium salicylate group perceived tinnitus. Fos-positive neurons were observed in all rats, while they appeared as typical dark dots, corresponding to a labeling restricted to their nucleus. NR2A protein was mainly expressed in the cytoplast and membrane of the cortical pyramidal cells. The expression of c-fos and NR2A immunoreactive neurons in auditory cortexes of the sodium salicylate group was significantly higher than that of other two control groups. CONCLUSIONS: The higher expression of c-fos and NR2A indicate that the neurotransmitters and receptors should be involved in the tinnitus, as well as suggest that neuronal plasticity occurs in the auditory cortex of rats experienced tinnitus, which may be played an important role in the mechanism of tinnitus.