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BACKGROUND In contrast to horses, the only evidence suggesting gastrointestinal disease in neonatal donkeys is associated with Group A rotaviruses (RVAs) is the detection of viral antigens by ELISA in just 1 of 82 symptomatic donkey foals. No additional, more comprehensive investigations have been conducted, and RVAs if circulating in donkey populations have not been molecularly characterised. OBJECTIVES To investigate if RVAs are associated with an outbreak of severe enteritis in neonatal donkeys and if associated determine the genotype(s) along with the phylogenetic relationship to RVA strains circulating in horses. STUDY DESIGN Cross-sectional. METHODS RT-PCR-based techniques were used for RVA diagnosis and gene amplification. Statistical significance was determined by Chi-square and Fisher's exact two-sided tests. Genotyping was performed by RotaC and phylogenetic analysis by neighbour joining. RESULTS In 2019, acute enteritis occurred in 119 of 206 donkey foals (≤4 months) at two intensive donkey farms in the Shandong province of China. The highest morbidity (68.1%), mortality (29.5%) and fatality levels (45.5%) occurred in foals in the 30-89 day, 30-59 day and 0-29 day age groups respectively. RVA gene sequences were detected in 107 (89.9%) of the symptomatic individuals while further analysis demonstrated the outbreak was associated with the same G3P[12] RVA strain designated RVA/Donkey-wt/CHN/Don01/2019/G3P[12]. Although the VP4 gene of Don01 exhibited close phylogenetic relationships with equivalent RVA sequences commonly circulating in horses, encoding VP7 was more closely associated with sequences isolated from bats suggesting this new donkey strain arose via an intergenogroup reassortment event. MAIN LIMITATIONS Actual prevalence not determined because

Diamond-copper/steel matrix abrasive composites were prepared by the roll-bonding technique. Firstly, the effects of the roll-bonding technical parameters (including sintering parameters, rolling parameters, and the component content) on the interfacial bonding strength in the composites were researched. Then, the surface macroscopic characteristics of the composites and the microstructures of the bonding interfaces were observed. The static compressive strength of the diamonds in the composites and the grinding performance of the composites were measured. Finally, the mechanisms for the effects of the roll-bonding technical parameters on the interfacial bonding strength were explored. The results showed that with increasing those parameters, the interfacial bonding strength between diamonds and the matrices displayed an initial increase and then a significant decrease. Furthermore, the optimal interfacial bonding strength (11.4 kN/m) and an excellent grinding performance (abrasive ratio of 23.2) were obtained from the diamond-steel matrix composites containing 10 vol% binder and 25% concentration of diamonds, when sintered at the temperature of 900 °C for holding time of 30 min and cold rolled at the reduction rate of 70%. The composites prepared with the optimum technical parameters had acceptable surface smoothness. In addition, the diamonds could be dispersed homogeneously in the matrices and firmly adhered to the substrates. When the diamond concentration was 25% in cold-rolling, the diamond-steel matrix composites showed better grinding performance. By improving the pressure condition of metallurgical bonding between diamonds and metal matrices from static pressure to rolling dynamic pressure, the sintering condition of temperature and holding time can be reduced and shortened, and the sintering condition effect on the interfacial bonding can be weaken. Thus, the application of the roll-bonding technique to the preparation of diamond-metal matrix composites could effectively avoid the thermal damage of diamonds caused by sintering process.

Teat papillomatosis is one important infectious disease affecting cattle health and results in significant economic losses especially in the dairy industry. Although there is a large number of commercial cattle herds in China, limited information is available for molecular epidemiological investigation of bovine papillomaviruses (BPVs). In October 2017, an outbreak of teat papillomatosis occurred in the Shandong Province of China. Samples were collected and diagnosed with PCR, and 3 full-length viral genomes were amplified from tissue samples collected from 3 outbreak farms. Analysis results revealed that the outbreak was associated with BPV type 10. This is the first report of BPV-10 infection in China and will contribute to the molecular epidemiological study of the disease.

Background Strangles is a highly contagious respiratory disease of equids caused by the bacterium Streptococcus equi subspecies equi. Objectives To identify the cause of an outbreak of strangles that occurred on donkey farms within the Shandong Province of China and determine the prevalence of the disease. Study design Cross-sectional. Methods Samples were taken from clinically affected animals to measure the prevalence of strangles within the population of donkeys at six intensive farms in China and identify the SeM type of isolate recovered from affected animals. Diagnosis was confirmed by bacterial isolation, biochemical tests and PCR. Epidemiological data were analysed using Chi-square test and a Fisher's exact two-sided test. The SeM gene of S. equi isolates recovered from affected animals was determined and compared with the SeM database PubMLST-seM. Results In July and August 2018, an outbreak of strangles occurred on six donkey farms within the Shandong Province of China. The overall prevalence of disease within the different donkey herds was 13.4%. Younger animals were worst affected with 40.3% (83/206) of donkey foals aged under 1 year exhibiting clinical signs compared with 12.5% (191/1525) of donkeys aged one to 2 years and 3.8% (17/442) of donkeys over 2 years of age. Analysis of SeM sequencing data identified that the farms were affected by the same strain of S. equi, SD201807, which contains the novel 136 allele of SeM. Main limitations Healthy donkeys were not sampled in this study. Conclusions The number of intensive donkey breeding farms in China has risen recently. The higher numbers of animals that are in closer proximity to one another raise the potential for the transmission of infectious diseases such as strangles. This is the first description of a strangles outbreak among donkey herds in China. The Summary is available in Chinese - see Supporting information.

To date, there have been no reports of coinfection with bovine papular stomatitis virus (BPSV) and bovine papillomavirus (BPV) in the same lesion. In the present study, one lingual papilloma-like sample was collected at an abattoir from the tongue of a 31-month-old Japanese black cow. Coinfection with BPSV and BPV was confirmed by histopathology, immunohistochemistry, PCR and RT-PCR. The evidence for coinfection with BPSV and BPV in the same lesion and an association of BPV with lingual papillomatosis will contribute to future epidemiological studies of these two viruses.