U.S. Department of Agriculture, Animal Natural Resources Institute, Animal Parasitic Disease Laboratory, Beltsville, MD 20705-2350, USA.
Vet Parasitol. 2010 Sep 20;172(3-4):195-203. doi: 10.1016/j.vetpar.2010.05.013. Epub 2010 May 16.
The Sand cat (Felis margarita) is a small-sized felid found in sand and stone deserts ranging from the north of Africa to Asia, with the Arabian Peninsula as its centre of distribution. The Sand cat captive breeding program at the Breeding Centre for Endangered Arabian Wildlife (BCEAW), Sharjah, UAE, has experienced high newborn mortality rates, and congenital toxoplasmosis was recently recognized as one of the causes of this mortality. In the present study, one 18-month-old Sand cat (FM019) died of acute toxoplasmosis-associated hepatitis and pneumonitis acquired after birth; Toxoplasma gondii was demonstrated in histological sections which reacted with T. gondii polyclonal antibodies by immunohistochemistry (IHC). T. gondii DNA was found by PCR of extracted DNA from liver and lung tissues of this cat. Antibodies to T. gondii were found in serum examined in 1:1600 dilution in the modified agglutination test (MAT); its 2-year-old cage mate seroconverted (MAT titer 1:3200) at the same time. Another Sand cat (FM017) was euthanized because of ill health when 3 years old; its MAT titer was >1:3200, and T. gondii tissue cysts were found in brain, heart, ocular muscles and skeletal muscle, confirmed by IHC. Viable T. gondii was isolated by bioassays in mice inoculated with tissues of another chronically infected Sand cat (FM002); T. gondii was not found in histological sections of this cat. T. gondii antibodies were found in several species of animals tested, notably in 49 of 57 wild felids at BCEAW. A 7-year-old Sand cat (3657) from Al Wabra Wildlife Preservation (AWWP), Doha, State of Qatar died of acute visceral toxoplasmosis with demonstrable T. gondii tachyzoites by IHC, and T. gondii DNA by PCR, and a MAT titer of >3200. T. gondii antibodies were found in 21 of 27 of wild felids at AWWP. PCR-RFLP genotyping at 10 genetic loci revealed that these T. gondii isolates from Sand cat (FM002 and FM019) at BCEAW have an atypical genotype, which was previously reported in T. gondii isolates of dogs from Sri Lanka. The genotype from the cat from AWWP (3657) is a genetic Type II strain with a Type I allele at locus Apico. This is the first report of genetic characterization of T. gondii isolates from Middle East.
沙丘猫（Felis margarita）是一种小型猫科动物，分布于从北非到亚洲的沙石荒漠地区，其分布中心位于阿拉伯半岛。阿联酋沙迦濒危阿拉伯野生动物繁育中心（BCEAW）的沙丘猫圈养繁殖计划曾面临较高的新生幼崽死亡率，最近发现先天性弓形虫病是导致这种死亡率的原因之一。在本研究中，一只 18 月龄的沙丘猫（FM019）死于出生后获得的急性弓形虫相关性肝炎和肺炎；组织病理学切片中通过免疫组织化学（IHC）显示出对 T. gondii 多克隆抗体的反应，证明存在弓形虫。通过对这只猫的肝和肺组织提取的 DNA 进行 PCR 检测，发现了 T. gondii DNA。在改良凝集试验（MAT）中，以 1:1600 的稀释度检测到血清中的 T. gondii 抗体；同时，它的 2 岁笼伴血清转化（MAT 滴度为 1:3200）。另一只 3 岁的沙丘猫（FM017）因健康状况不佳而被安乐死；其 MAT 滴度>1:3200，通过 IHC 证实脑、心脏、眼肌和骨骼肌中存在弓形虫组织囊肿。通过对另一只慢性感染的沙丘猫（FM002）的组织进行生物测定，从组织中分离出了活的 T. gondii；在这只猫的组织学切片中未发现 T. gondii。在测试的几种动物中发现了 T. gondii 抗体，尤其是在 BCEAW 的 57 只野生猫科动物中有 49 只。卡塔尔多哈的 Al Wabra 野生动物保护中心（AWWP）的一只 7 岁沙丘猫（3657）死于急性内脏弓形虫病，IHC 显示有速殖子，PCR 检测到 T. gondii DNA，MAT 滴度>3200。在 AWWP 的 27 只野生猫科动物中有 21 只发现了 T. gondii 抗体。在 10 个遗传位点的 PCR-RFLP 基因分型显示，BCEAW 的沙丘猫（FM002 和 FM019）的这些 T. gondii 分离株具有一种非典型基因型，此前在斯里兰卡的犬弓形虫分离株中也有报道。来自 AWWP（3657）的猫的基因型是遗传 II 型菌株，在 Apico 基因座有 I 型等位基因。这是中东地区首次报道 T. gondii 分离株的基因特征。
