Yang YuRong, Feng YongJie, Yao QiuXia, Wang YingHua, Lu YaoYao, Liang HongDe, Zhu XingQuan, Zhang LongXian
College of Animal Science and Veterinary Medicine, Henan Agricultural University Zhengzhou, China.
State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences Lanzhou, China.
Front Microbiol. 2017 Feb 3;8:136. doi: 10.3389/fmicb.2017.00136. eCollection 2017.
is an important cause of reproductive failure in small ruminants that also poses a risk to consumers who consume undercooked meat. However, little is known about sheep toxoplasmosis in China for the world. Therefore, this study was conducted to assess the prevalence of infection in sheep from China, to isolate via bioassay in mice and to evaluate the virulence of the isolated based on vero cell invasion and mice. A total of 840 samples (304 unfrozen hearts and 536 sera) from sheep in China were collected from 2014 to 2016. Heart samples ( = 36) of seropositive sheep (MAT, ≥25) were bioassayed in mice individually. DNA derived from cell cultured tachyzoites of the isolated was characterized by PCR-RFLP of 10 loci (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico). The virulence of the was evaluated based on the mortality and encystation in mice, as well as their growth characteristics in cell culture. Antibodies to were found in 174 of 840 (20.71%, 304 hearts juice and 536 sera) sheep by the modified agglutination test (cut-off 1:25). Viable was isolated from the hearts of two of 36 seropositive sheep hearts. Both genotypes of the sheep heart isolates were ToxoDB#9. The virulence of the two ToxoDB#9 isolations varied significantly. To the best of our knowledge, this is the first report of isolation of ToxoDB#9 strain of from sheep in China.
是小型反刍动物繁殖失败的重要原因，对食用未煮熟肉类的消费者也构成风险。然而，中国绵羊弓形虫病在世界范围内鲜为人知。因此，本研究旨在评估中国绵羊的感染率，通过小鼠生物测定法分离弓形虫，并基于vero细胞侵袭和小鼠来评估分离出的弓形虫的毒力。2014年至2016年，共收集了来自中国绵羊的840份样本（304份未冷冻心脏和536份血清）。对36份血清学阳性绵羊（MAT，≥25）的心脏样本分别在小鼠中进行生物测定。通过对10个基因座（SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1和Apico）进行PCR-RFLP，对分离出的弓形虫细胞培养速殖子的DNA进行特征分析。基于小鼠的死亡率和包囊形成以及它们在细胞培养中的生长特性，评估弓形虫的毒力。通过改良凝集试验（临界值1:25）在840只绵羊中的174只（20.71%，304份心脏汁液和536份血清）中检测到抗弓形虫抗体。从36份血清学阳性绵羊心脏中的两份心脏中分离出活的弓形虫。绵羊心脏分离株的两种基因型均为ToxoDB#9。两种ToxoDB#9分离株的毒力差异显著。据我们所知，这是中国首次从绵羊中分离出ToxoDB#9株弓形虫的报告。
