Staphylococcus aureus (SA) is representative of gram-positive bacteria. Sanguinarine chloride hydrate (SGCH) is the hydrochloride form of sanguinarine (SG), one of the main extracts of Macleaya cordata (M. cordata). There are few reports on its antibacterial mechanism against SA. Therefore, in this study, we investigated the in vitro antibacterial activity and mechanism of SGCH against SA. The inhibitory zone, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) were measured, and the bactericidal activity curve was plotted. In addition, the micromorphology, alkaline phosphatase (AKP) activity, Na⁺K⁺, Ca²⁺Mg²⁺-adenosine triphosphate (ATP) activity, intracellular reactive oxygen species (ROS), and fluorescein diacetate (FDA) were observed and detected. The results showed that the inhibitory zone of SGCH against SA was judged as medium-sensitive; the MIC and MBC were 128 and 256 μg/mL, respectively; in the bactericidal activity curve, SGCH with 8 × MIC could completely kill SA within 24 h. SGCH was able to interfere with the integrity and permeability of the SA cell wall and membrane, as confirmed by the scanning electron microscopy (SEM) images, the increase in extracellular AKP and Na⁺ K⁺, Ca²⁺ Mg²⁺-ATP activities as well as the fluorescein diacetate (FDA) staining experiment results. Moreover, a high concentration of SGCH could induce SA to produce large amounts of ROS. In summary, these findings revealed that SGCH has a preferable antibacterial effect on SA, providing an experimental and theoretical basis for using SG as an antibiotic substitute in animal husbandry and for the clinical control and treatment of diseases caused by SA.

Foot-and-mouth disease (FMD) is classified as a Class I animal disease in China and listed as one of the notifiable animal diseases by the World Organization for Animal Health (WOAH). It significantly impacts the safe production of livestock and the trade of animals and related products. China’s Yunnan Province shares a 710 km border with Laos, with frequent cross-border trade, and the cross-border flow of animals and related products occurs from time to time. In order to prevent the introduction of FMD from the border areas of Laos into China, this study conducted an assessment of the entry, exposure, and consequences of FMD transmission. The findings revealed a “high” risk in terms of entry assessment, a “medium” risk in exposure assessment, and a “high” risk in the consequence assessment. Based on these assessments, the overall risk level for the introduction of FMD from Laos into China is determined to be “high”. Therefore, it is recommended that management measures are implemented, such as restricting animal movement across borders and strengthening inspection procedures for animals entering China, to effectively prevent FMD introduction from Laos.

Epizootic haemorrhagic disease (EHD) is an infectious, non-contagious viral disease of ruminants caused by epizootic haemorrhagic disease virus (EHDV) and is transmitted by insects of the genus Culicoides. In 2008, EHD was listed on the World Organization for Animal Health (WOAH) list of notifiable terrestrial and aquatic animal diseases. This article reviews the distribution of EHD in China and relevant studies and proposes several suggestions for the prevention and control of EHD. There have been reports of positivity for serum antibodies against EHDV-1, EHDV-2, EHDV-5, EHDV-6, EHDV-7, EHDV-8 and EHDV-10 in China. Strains of EHDV-1, -5, -6, -7, -8 and -10 have been isolated, among which the Seg-2, Seg-3 and Seg-6 sequences of serotypes -5, -6, -7 and -10 belong to the eastern topotype. The emergence of western topotype Seg-2 in EHDV-1 strains indicates that EHDV-1 strains in China are reassortant strains of the western and eastern topotypes. A novel serotype strain of EHDV named YNDH/V079/2018 was isolated in 2018. Chinese scholars have successfully expressed the EHDV VP7 protein and developed a variety of ELISA detection methods, including antigen capture ELISA and competitive ELISA. A variety of EHDV nucleic acid detection methods, including RT–PCR and qRT–PCR, have also been developed. LAMP and the liquid chip detection technique are also available. To prevent and control EHD, several suggestions for controlling EHD transmission have been proposed based on the actual situation in China, including controlling the number of Culicoides, reducing contact between Culicoides and hosts, continued monitoring of EHDV and Culicoides in different areas of China and further development and application of basic and pioneering research related to EHD prevention and control.

Bluetongue (BT) is a vector‐borne viral disease caused by the bluetongue virus (BTV), which can affect a variety of wild and domestic ruminants. Due to its significant impact on ruminant health and national economies, BT is classified as a notifiable multispecies disease by the World Organization for Animal Health (WOAH). In China, BT is listed as a Class II multispecies animal disease. This article provides a comprehensive review of the distribution of BTV and its primary insect vector, Culicoides , in China. Since BTV was first reported in China in 1979, BTV antibody‐positive samples have been detected in most parts of the country, with a total of 17 serotypes of BTV isolated (BTV‐1, 2, 3, 4, 5, 7, 9, 11, 12, 14, 15, 16, 17, 20, 21, 24, and 29). Culicoides are widely distributed across China. Currently, studies have been conducted on climatic factors influencing their distribution and blood‐sucking habits. To improve the efficiency of BTV detection in China, various detection methods have been explored, including polymerase chain reaction (PCR), loop‐mediated isothermal amplification (LAMP), bio‐bar code assay (BCA) for viral detection, as well as enzyme‐linked immunosorbent assay (ELISA), agar gel immunodiffusion (AGID) and colloidal gold immunochromatography test strips for antibody detection. Additionally, inactivated vaccines, attenuated vaccines, and recombinant vaccines were also investigated. This review summarizes the current knowledge on BTV vectors, viruses, and surveillance, as well as the development of BT vaccines in China. In light of the current situation of BT in China, it proposes comprehensive prevention and control recommendations, including enhancing awareness of the hazards of BT, implementing an integrated prevention and control technology system, and strengthening research related to BT prevention and control.