BackgroundSika deer (Cervus nippon) have different dietary preferences to other ruminants and are tolerant to tannin-rich plants. Because the rumen bacteria in domestic Sika deer have not been comprehensively studied, it is important to investigate its rumen bacterial population in order to understand its gut health and to improve the productivity of domestic Sika deer.ResultsThe rumen bacterial diversity in domestic Sika deer (Cervus nippon) fed oak leaves- (OL group) and corn stalks-based diets (CS group) were elucidated using 16S rRNA gene libraries and denaturing gradient gel electrophoresis (DGGE). Overall, 239 sequences were examined from the two groups, 139 clones from the OL group were assigned to 57 operational taxonomic units (OTUs) and 100 sequences from the CS group were divided into 50 OTUs. Prevotella-like sequences belonging to the phylum Bacteroidetes were the dominant bacteria in both groups (97.2% OL and 77% CS), and sequences related to Prevotella brevis were present in both groups. However, Prevotella shahii-like, Prevotella veroralis-like, Prevotella albensis-like, and Prevotella salivae-like sequences were abundant in the OL group compared to those in the CS group, while Succinivibrio dextrinosolvens-like and Prevotella ruminicola-like sequences were prevalent in the CS group. PCR-DGGE showed that bacterial communities clustered with respect to diets and the genus Prevotella was the dominant bacteria in the rumen of domestic Sika deer. However, the distribution of genus Prevotella from two groups was apparent. In addition, other fibrolytic bacteria, such as Clostridium populeti and Eubacterium cellulosolvens were found in the rumen of domestic Sika deer.ConclusionsThe rumen of domestic Sika deer harbored unique bacteria which may represent novel species. The bacterial composition appeared to be affected by diet, and sequences related to Prevotella spp. may represent new species that may be related to the degradation of fiber biomass or tannins. Moreover, the mechanism and biological functions of Prevotella spp. in the rumen ecosystem, and synergistic interactions with other microorganisms should be noticed.

Background Coronavirus disease 2019 (COVID-19), a contagious infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread across the world. Apart from respiratory complications, an increasing number of patients with ischemic stroke have been reporting. Objective This systematic review and meta-analysis aims to explore the characteristics of ischemic stroke after SARS-CoV-2 infection, and provides valuable reference materials for subsequent clinical treatment. Materials and methods PubMed, Web of Science, and Ovid-Embase databases were searched up to 24th March 2021. We utilized the search strategy of medical subject headings combined with entry terms to search all related literatures. All studies identified with the electronic and manual searches were listed by citation, title

Sika deer (Cervus nippon) rely on microorganisms living in the rumen to convert plant materials into chemical compounds, such as volatile fatty acids (VFAs), but how the rumen bacterial community is affected by different forages and adapt to altered diets remains poorly understood. The present study used 454-pyrosequencing of bacterial 16S ribosomal RNA (rRNA) genes to examine the relationship between rumen bacterial diversity and metabolic phenotypes using three sika deer in a 3 × 3 latin square design. Three sika deer were fed oak leaves (OL), corn stover (CS), or corn silage (CI), respectively. After a 7-day feeding period, when compared to the CS and CI groups, the OL group had a lower proportion of Prevotella spp. and a higher proportion of unclassified bacteria belonging to the families Succinivibrionaceae and Paraprevotellaceae (P<0.05). Meanwhile, the concentration of isobutyrate was significantly lower (P<0.05) in the OL group than in the CS and CI groups. There was no significant change of dominant bacterial genera in the OL group after 28 days of feeding. Conversely, total volatile fatty acids (TVFAs) showed an increase after 28 days of feeding, mainly due to the increasing of acetate, propionate, and valerate (P<0.05). The interplay between bacteria and metabolism in the OL group differed from that in the CS and CI groups, especially for the interaction of TVFAs and acetate/propionate. Overall, the current study suggested that Prevotella spp. played critical roles in the fermentation of feed in the rumen of sika deer. However, the differences in interplay patterns between rumen bacterial community composition and metabolic phenotypes were altered in the native and domesticated diets indicating the changed fermentation patterns in the rumen of sika deer.