In this study, significant differences in the prevalence of were observed between different age groups of yaks ( 0.05). parasite intracellulaire largement rpandu dans le monde. Des tudes ont indiqu la prsence dune infection par chez les animaux dans certaines provinces de Chine, mais on conna?t peu linfection par chez les yaks (ont t dtects par dosage immuno-enzymatique (ELISA) chez 261 yaks (9,38 %). Nous avons constat JMS que la sroprvalence diffrait considrablement entre les diffrents comts (allant de 5,41 % Gangcha 19,79 % Datong), dune anne lautre dans la rgion autonome du Tibet (de 2,34 % en 2018 13,24 % en 2019), et par age (de 5,59 % pour les animaux de moins dun an 11,76 % pour ceux ags de plus de 7 ans) ( 0,05). Le climat, les conditions gographiques et lage sont les principaux facteurs influen?ant linfection chez les yaks de ces rgions. Par consquent, notre tude fournit des donnes de rfrence pour la sant publique et la prvention de la toxoplasmose du yak. Introduction is an obligate intracellular parasite that infects various host species worldwide, including yak (infection usually does not show any obvious symptoms; however, in patients with weak immune function or immunodeficiency, such as acquired immunodeficiency syndrome (AIDS) patients, infection can lead to serious diseases including epilepsy, encephalitis, retinitis, and even death with virulent strains of [14, 25, 26]. Acute infection is followed by asymptomatic dormant infection when parasites develop in numerous organs, such as the skeletal/cardiac muscles, retina, and brain parenchyma [27]. Dormant infection can reboot in immunocompromised patients, with alteration of dormant bradyzoites into duplicating tachyzoites leading to substantial morbidity and 100% mortality [20]. Previous studies have Propionylcarnitine shown that infection during pregnancy can lead to miscarriage, premature birth, birth defects, or intellectual disability [7]. The domestic yak ([28]. Rodents and small animals are also intermediate hosts of and carnivores such as the Snow leopard (oocysts. Nowadays, serological assays are widely used for the clinical diagnosis of toxoplasmosis and these include the indirect hemagglutination test (IHA), indirect fluorescent antibody test (IFAT), and enzyme-linked immunosorbent assay (ELISA) [4, 23, 28]. Previously, studies have reported that the seroprevalence of infection in yaks in the QinghaiCTibetan Plateau of China is between 2.3% and 35.1% [15, 17, 18]. However, Propionylcarnitine the prevalence rate differed depending on geographical location. In remote areas of the plateau, infection of yaks can cause greater economic losses and threaten other animals and human health. In order to enrich the information on the prevalence and distribution of infection in yaks in the QinghaiCTibet Plateau, sera of yaks were collected between 2018 and 2019 and antibodies were monitored. Our results demonstrate the dynamic epidemic situation of toxoplasmosis in yaks in the QinghaiCTibet Plateau, and provide support for control of infection in yaks and food security. Materials and methods Ethics statement The experimental protocol was authorized by the ethics committee of Shanghai Veterinary Study Institute, Chinese Academy of Agricultural Sciences, authorization quantity (SHVRI-SZ-201811015-03). Propionylcarnitine Sampling sites and blood collection The blood samples of yaks used in this study were collected from six counties Propionylcarnitine (Wulan, Gangcha, Huangzhong, Guinan, Qilian, and Datong) in Qinghai Province having a latitude of 3509C3835N, and longitude of 9701C10156E (Fig. 1), and two counties (Seni and Nyainrong) in the Tibet Autonomous Region with latitude of 3031C3324N, and longitude of 9112C9356E (Fig. 2). A total of 2784 blood samples were collected from your jugular vein of yaks from 2018 to 2019. Disposable blood collection needles (LuTai, ST1021, Shandong, PR China) and vacuum blood collection tubes (BD-Pharmingen, 367820, USA) were used to collect blood samples. Yak owners were asked to provide info on the age and sex of the animal using a questionnaire. After collection, blood samples were centrifuged at 1 500 for 15 min and sera were separated and transferred to 1.5 mL Eppendorf tubes. The serum samples were stored at ?80 C until use. Open in a separate windowpane Number 1 Map of sampling counties in Qinghai with this study. The reddish dots show the sampling sites. Open in a separate windowpane Number 2 Map of sampling counties in Tibet with this study. The reddish dots show the sampling sites. Detection of antibodies Antibodies for were determined using a commercial IgG enzyme-linked immunosorbent assay (ELISA) Kit (Indical Bioscience, Leipzig, Germany). Both positive and negative control sera were available in the kit. The diluted serum sample (1:100) was incubated for 60 min at space temp in the assay well and then washed three times. Then 100 L of conjugate was added to each well and incubated for 30 min at space temperature. The plate was again washed three times and the chromogenic enzyme substrate was added at a concentration of 100 L and incubated for 10 min at.
