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Lumpy skin disease virus (LSDV) is capable of causing transboundary diseases characterized by fever, nodules on the skin, mucous membranes, and inner organs. The disease may cause emaciation with the enlargement of lymph nodes and sometimes death. It has had endemic importance in various parts of Asia in recent years, causing substantial economic losses to the cattle industry. The current study reported a suspected LSDV infection (based on signs and symptoms) from a mixed farm of yak and cattle in Sichuan Province, China. The clinical samples were found positive for LSDV using qPCR and ELISA, while LSDV DNA was detected in Culex tritaeniorhynchus Giles. The complete genome sequence of China/LSDV/SiC/2021 was determined by Next-generation sequencing. It was found that China/LSDV/SiC/2021 is highly homologous to the novel vaccine-related recombinant LSDV currently emerging in China and countries surrounding China. Phylogenetic tree analysis revealed that the novel vaccine-associated recombinant LSDV formed a unique dendrograms topology between field and vaccine-associated strains. China/LSDV/SiC/2021 was found to be a novel recombinant strain, with at least 18 recombination events via field viruses identified in the genome sequence. These results suggest that recombinant LSDV can cause high mortality in yaks, and its transmission might be due to the Culex tritaeniorhynchus Giles, which acts as a mechanical vector.

Short-chain fatty acids (SCFA) are principal nutrient substrates of intestinal epithelial cells that regulate the epithelial barrier in yaks. Until now, metagenomics sequencing has not been reported in diarrheal yaks. Scarce information is available regarding the levels of fecal SCFA and diarrhea in yaks. So, our study aims to identify the potential pathogens that cause the emerging diarrhea and explore the potential relationship of short-chain fatty acids in this issue. We estimated diarrhea rate in yaks after collecting an equal number of fecal samples from affected animals. Metagenomics sequencing and quantitative analysis of SCFA were performed, which revealed 15%–25% and 5%–10% prevalence of diarrhea in yak’s calves and adults, respectively. Violin box plot also showed a higher degree of dispersion in gene abundance distribution of diarrheal yaks, as compared to normal yaks. We found 366,163 significant differential abundance genes in diarrheal yaks, with 141,305 upregulated and 224,858 downregulated genes compared with normal yaks via DESeq analysis. Metagenomics binning analysis indicated the higher significance of bin 33 (Bacteroidales) (p p p p p p n = 4), class (n = 8), oder (n = 8), family (n = 16), genus (n = 17), and species (n = 30) was noticed, respectively. Compared with healthy yaks, acetic acid (p p p p p p Staphylococcus aureus, Babesia ovata, Anaplasma phagocytophilum, Bacteroides fluxus, viruses, Klebsiella pneumonia, and inflammation-related bacteria, the decrease of SCFA caused by the imbalance of intestinal microbiota was potentially observed in diarrheal yaks.

The pond has a complex microbial ecosystem, including microorganisms in water and sediment, which plays an important role in the health of fish and water quality. The microbial community structure in the ponds can be easily affected by many factors. However, not much is known about the role of different aquaculture model and fish on the microbial community structure in ponds. The purpose of the study was to investigate the microbial diversity and composition of the ponds with different aquaculture model and fish by high-throughput sequencing. A total of 3835072 valid sequences were achieved from 60 samples. Additionally, 2064 and 1917 core OTUs were observed in water and sediment samples, respectively. Our results suggested that sediment samples have a higher abundance and diversity of microbial community than water samples. In all the samples, the four most dominant phyla were Proteobacteria, Cyanobacteria, Actinomycetes and Bacteroides. At the genus level, hgcI_clade and CL500-29_marine_group were the dominant bacteria shared by the water samples and sediment samples. In addition, more bacteria related to eutrophication were found in the group of BF, BC and HSB, which suggested that these ponds may have been eutrophicated. In conclusion, the present study revealed the differences in the structure and diversity of microbial communities in ponds with different aquaculture model and fish. Furthermore, changes in typical bacteria of the ponds contribute to detect water quality and prevent water eutrophication.

The intestinal protozoan specie, Cryptosporidium causes serious diarrheal syndrome in humans and animals worldwide. However, limited knowledge is known about the infection caused by this specie in yaks in Naqu. About 950 serum and 150 fecal samples were collected and assayed by using commercial ELISA kits and nPCR detection methods to find the prevalence and molecular characterization of Cryptosporidium spp. in yaks. Results found that 103 out of 950 (10.8%) serums were uncovered against C. parvum antibodies. In different regions, the prevalence of C. parvum in yaks were in a range from 9.1% to 16.7%, with obvious difference among the three areas (P 0.001). In male and female yaks, the prevalence of C. parvum was found to be 7.2% and 13.3% respectively (P 0.001); and a significant difference (P 0.001) with a range of 9.8%-18.2% was observed among different age groups. Out of 150 fecal samples, only 2 (1.3%) positive samples were detected via nPCR. The positive samples were sequenced and identified to be C. bovis. The two isolates were clustered to cattle and yak clade separately. Our results highlight the prevalence and epidemiological status of Cryptosporidium spp. in yaks which may contribute towards the prevention and control of this zoonotic disease in Naqu, China.