Fredebaugh Shannon L, Mateus-Pinilla Nohra E, McAllister Milton, Warner Richard E, Weng Hsin-Yi
Illinois Natural History Survey, Institute of Natural Resource Sustainability, University of Illinois, 1816 South Oak St., Champaign, Illinois 61820, USA.
J Wildl Dis. 2011 Apr;47(2):381-92. doi: 10.7589/0090-3558-47.2.381.
We conducted a cross-sectional study from 2008 to 2009 to evaluate the occurrence of feral and wild cats and the risk of Toxoplasma gondii infection in terrestrial wildlife in a natural area in Illinois, USA. Felids are definitive hosts for T. gondii and cats are a key component of rural and urban transmission of T. gondii. We selected four forest sites within the interior of the park and four edge sites within 300 m of human buildings. Feline and wildlife occurrence in the natural area was determined with the use of scent stations, motion-detection cameras, and overnight live trapping. Based on scent stations and trapping, feral cats used building sites more than forest sites (scent stations: P=0.010; trapping: P=0.083). Prevalence of T. gondii antibodies was determined with the use of the indirect immunofluorescent antibody test (IFAT) with a titer of 1:25 considered positive; T. gondii antibodies were detected in wildlife at all sites. Wildlife species were classified as having a large home range (LHR) or a small home range (SHR), based on published estimates and using a cutoff of 100 ha. Small-home-range mammals had a higher prevalence of antibody to T. gondii (odds ratio [OR]=4.2; P=0.018) at sites with a high frequency of cat occurrence (defined as ≥ 9 cat occurrences across three detection methods); this finding indicates that feral cats are the most likely source of environmental contamination. Overall, the prevalence of antibody to T. gondii among LHR mammals was significantly higher than the prevalence among SHR mammals (OR=7.1; P<0.001). Small-home-range mammals are an essential part of T. gondii-antibody prevalence studies and can be used as sentinels for risk of disease exposure to humans and wildlife in natural areas. This study improves our understanding of ecologic drivers behind the occurrence of spatial variation of T. gondii within a natural area.
2008年至2009年，我们开展了一项横断面研究，以评估美国伊利诺伊州一个自然区域内野猫和野生猫科动物的出现情况以及陆地野生动物感染弓形虫的风险。猫科动物是弓形虫的终末宿主，而猫是弓形虫在农村和城市传播的关键因素。我们在公园内部选择了四个森林地点，并在距离人类建筑300米范围内选择了四个边缘地点。通过使用气味站、运动检测相机和夜间活体诱捕来确定自然区域内猫科动物和野生动物的出现情况。基于气味站和诱捕结果，野猫对建筑工地的利用多于森林地点（气味站：P = 0.010；诱捕：P = 0.083）。通过使用间接免疫荧光抗体试验（IFAT）测定弓形虫抗体的流行率，滴度为1:25被视为阳性；在所有地点的野生动物中均检测到了弓形虫抗体。根据已发表的估计数据，并使用100公顷的临界值，将野生动物物种分类为具有大栖息地范围（LHR）或小栖息地范围（SHR）。在猫出现频率较高的地点（定义为通过三种检测方法猫出现次数≥9次），小栖息地范围的哺乳动物对弓形虫抗体的流行率更高（优势比[OR]=4.2；P = 0.018）；这一发现表明野猫是环境污染的最可能来源。总体而言，LHR哺乳动物中弓形虫抗体的流行率显著高于SHR哺乳动物（OR = 7.1；P < 0.001）。小栖息地范围的哺乳动物是弓形虫抗体流行率研究的重要组成部分，可作为自然区域内人类和野生动物疾病暴露风险的哨兵。这项研究增进了我们对自然区域内弓形虫空间变异发生背后生态驱动因素的理解。
