State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China.
Vet Parasitol. 2012 Jun 8;187(1-2):53-6. doi: 10.1016/j.vetpar.2011.12.036. Epub 2012 Jan 8.
Toxoplasmosis in pigs is a large threat to pig industry as well as pork consumers. Most pigs become infected by ingestion of oocysts from contaminated environment (soil, water and feed) or infected animal tissues postnatally. In the present study, field studies were conducted to evaluate the relationship between soil contamination status of Toxoplasma gondii oocysts and T. gondii infection in pigs in 12 pig farms with different density of cats in central China. The presence of T. gondii oocysts in soil were determined by PCR and loop-mediated isothermal amplification (LAMP). T. gondii DNA was found in 11 farms with different cat density excepting one farm exposed to low cat density. Twenty (21.1%) and 36 (37.9%) of 95 soil samples were T. gondii positive by PCR and LAMP, respectively (0.01<P<0.05). Soil contamination was found with significant difference in statistics between farms with high and low cat density by PCR (0.01<P<0.05), and highly significant differences by LAMP (P<0.01). Additionally, a total of 2277 sera were collected to determine the presence of IgG antibodies against T. gondii using AG-ELISA. Antibodies were found in 453 of 1238 (36.6%) samples from pig farms with high cat density and 220 of 1039 (21.2%) samples from pig farms with low cat density (P<0.01). The results indicated that a high seroprevalence of T. gondii in pigs was found in the pig farms with high soil contamination by T. gondii oocysts in Hubei Province. The soil contamination status of pig farms was significantly influenced by cat density and may be an indicator of T. gondii infection in pigs.
猪弓形虫病是猪业和猪肉消费者的一大威胁。大多数猪通过摄入受污染的环境（土壤、水和饲料）或产后感染的动物组织中的卵囊而感染。在本研究中，在中国中部的 12 个不同猫密度的猪场进行了现场研究，以评估土壤中弓形虫卵囊污染状况与猪弓形虫感染之间的关系。通过 PCR 和环介导等温扩增（LAMP）检测土壤中是否存在弓形虫卵囊。除了一个暴露在低猫密度下的农场外，在 11 个具有不同猫密度的农场中都发现了 T. gondii DNA。通过 PCR 和 LAMP，20（21.1%）和 36（37.9%）个 95 个土壤样本中 T. gondii 呈阳性（0.01<P<0.05）。PCR 检测到高猫密度和低猫密度猪场之间的土壤污染存在统计学差异（0.01<P<0.05），LAMP 检测到高度显著差异（P<0.01）。此外，共采集了 2277 份血清，使用 AG-ELISA 检测 T. gondii 的 IgG 抗体。在高猫密度猪场的 1238 份（36.6%）样本和低猫密度猪场的 1039 份（21.2%）样本中发现了抗体（P<0.01）。结果表明，在湖北省高土壤弓形虫卵囊污染的猪场中，猪弓形虫的血清阳性率很高。猫密度显著影响猪场的土壤污染状况，可能是猪弓形虫感染的一个指标。
