Discovery and genetic characterization of novel paramyxoviruses from small mammals in Hubei Province, Central China.

Paramyxoviruses are a group of single-stranded, negative-sense RNA viruses, some of which are responsible for acute human disease, including parainfluenza virus, measles virus, Nipah virus and Hendra virus. In recent years, a large number of novel paramyxoviruses, particularly members of the genus Jeilongvirus, have been discovered in wild mammals, suggesting that the diversity of paramyxoviruses may be underestimated. Here we used hemi-nested reverse transcription PCR to obtain 190 paramyxovirus sequences from 969 small mammals in Hubei Province, Central China. These newly identified paramyxoviruses were classified into four clades: genera Jeilongvirus, Morbillivirus, Henipavirus and Narmovirus, with most of them belonging to the genus Jeilongvirus. Using Illumina sequencing and Sanger sequencing, we successfully recovered six near-full-length genomes with different genomic organizations, revealing the more complex genome content of paramyxoviruses. Co-divergence analysis of jeilongviruses and their known hosts indicates that host-switching occurred more frequently in the evolutionary histories of the genus Jeilongvirus. Together, our findings demonstrate the high prevalence of paramyxoviruses in small mammals, especially jeilongviruses, and highlight the diversity of paramyxoviruses and their genome content, as well as the evolution of jeilongviruses.

Pathogenic Leptospira Infections in Hubei Province, Central China.

Leptospirosis is an important zoonosis that is caused by pathogenic Leptospira, which is considered to be a re-emerging infectious disease in many countries. Rodents are the most important reservoirs for both human and animal infection. An epidemiological survey of pathogenic Leptospira in rodents is important for the prevention and control of leptospirosis. In this study, a total of 964 rodents were captured from six cities in Hubei Province, and two pathogenic Leptospira species (L. interrogans and L. borgpetersenii) were detected using nested PCR with an overall prevalence of 4.8%. L. interrogans was distributed in five sampling sites, which may be the dominant species of pathogenic Leptospira in Hubei Province. In addition, Rattus norvegicus showed a relatively high infection rate, which may play an important role in the transmission and infection of pathogenic Leptospira. This study reveals the prevalence of pathogenic Leptospira in wild rodents in Hubei Province, suggesting that the risk of leptospirosis infection in Hubei Province still exists.

Grazing and Supplementation of Dietary Yeast Probiotics Shape the Gut Microbiota and Improve the Immunity of Black Fattening Goats (Capra hircus).

This study aimed to investigate the effects of different feeding modes on the growth performance, gut microbiota, and immunity of Black Fattening Goat (Capra hircus). A total of 30 goats were grouped in three groups by their feeding modes (pasture grazing group, PG; barn feeding group, BF; barn feeding + probiotics, BF + P; n = 10) and the study was performed for 114 days. After a 2-week adaptation period, the first growth performance test was conducted, and the blood and fecal samplings (day 0) were collected on January 17, 2020, while the second and third test and samplings were conducted on days 53 and 100 of feeding. The species-composition of fecal microbiota was analyzed by 16S ribosomal RNA gene-sequencing using PacBio single molecule real time (SMRT) sequencing technology. Both the BF and BF + P groups had the highest (P < 0.05) body's weight and length, and chest circumference at days 53 and 100, especially at day 100, the body's weight of both the BF groups were more than 18 kg. The levels of immunoglobulin A (IgA) and immunoglobulin G (IgG) were found to be significantly higher (P < 0.05) in the PG and BF + P groups at day 100. The PG group exhibited the highest number of operational taxonomic unit (OTUs) and alpha diversity. Firmicutes, Bacteroidetes, and Verrucomicrobia were the predominant phyla in all the fecal samples. The relative abundance of Akkermansia muciniphila and Ruminococcus flavefaciens were found to be significantly higher (P < 0.05) in PG group and BF + P group at day 100, respectively, which might partially explain the significantly higher (P < 0.05) levels of IgA and IgG in these two groups. These findings suggested that BF supplemented with 5 g probiotics (Saccharomyces cerevisiae and mannan oligosaccharides) per day has the potential to enhance the growth and immunity of Black Fattening Goats.

Complete sequence and characterization of mitochondrial genome of Jianyang Daer goat (Capra hircus).

This study has presented the complete mitogenome of Jianyang Daer goat (Capra hircus), a crossbreed known for its high growth rate and good-meat quality in China. The mitogenome was 16,643 bp in length, including 33.54% A, 26.07% C, 13.10% G and 27.29% T. It contained a non-coding control region, 2 ribosomal RNA genes, 13 protein-coding genes and 22 transfer RNA genes. Two kinds of inititiation codon and four types of termination codon were identified. Moreover, most of the genes were encoded on H-strand. These information will be useful for further investigation on the genetic divergence among Chinese domestic goats.

Role of microRNA-101a in the regulation of goat skeletal muscle satellite cell proliferation and differentiation.

MicroRNAs are a class of small, non-coding RNAs that participate in the regulation of diverse biological processes including skeletal muscle development. However, the underlying molecular mechanisms are not fully understood, particularly in goat. Here, we identified goat miR-101a as a novel myogenic microRNA mediating myogenic differentiation. The expression of miR-101a was enriched in goat skeletal muscles and up-regulated during satellite cell differentiation. After transfection with a miR-101a mimic and culturing in differentiation medium, satellite cell differentiation was promoted, accompanied by a significant increase in mRNA expression of the myogenic marker, MyoG, and decreased expression of MyoD. In contrast, blocking the function of miR-101a with a 2'-O-methylated antisense oligonucleotide inhibitor repressed satellite cell differentiation. However, both gain- and loss-of-function studies demonstrated that miR-101a had no significant influence on satellite cell proliferation. Therefore, our results provide a new insight on miR-101a in the regulation of goat skeletal muscle satellite cell proliferation and differentiation.