Referral Veterinary Diagnostic and Extension Centre, LUVAS, Uchani, Karnal, 132001, Haryana, India.
Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, 125001, Haryana, India.
Parasitol Res. 2022 May;121(5):1487-1497. doi: 10.1007/s00436-022-07489-5. Epub 2022 Mar 22.
Ovine theileriosis is an important tick-borne haemoprotozoan disease of sheep in tropical and subtropical regions, causing severe productivity and economic loss. There is a paucity of information related to molecular studies of ovine theileriosis from India. The present study identified different Theileria spp. in naturally infected sheep using nested PCR-restriction fragment length polymorphism (nPCR-RFLP). Blood samples and ticks were collected from 204 sheep in different agro-climatic zones of Haryana state, India, during the tick active season. Microscopic examination of thin blood smears revealed 33.3% (68/204) infections with Theileria spp., while 44.6% (91/204) of blood samples were positive by nPCR assay. Different Theileria spp. were identified based upon RFLP patterns using four restriction enzymes: Hpa II, Bsh 1285I, Hae II and Rsa I. Out of 91 positive samples, 50.5% (46/91), 23.08% (21/91), 11% (10/91) and 2.2% (2/91) were positive for T. ovis, T. lestoquardi, T. luwenshuni (Theileria sp. China 1/Theileria sp. China) and T. annulata, respectively. Mixed infection was detected in 13.2% (12/91) of cases. Based upon HpaII enzymatic digestion pattern, two samples with T. lestoquardi and T. annulata, nine samples with T. lestoquardi and T. ovis and one sample with T. ovis and T. annulata were detected. The presence of these Theileria spp. was further confirmed by sequence analysis. The majority of ticks collected from sheep were identified as Rhipicephalus spp. followed by Hyalomma anatolicum and Hemaphysalis spp. The present investigation depicts the first comprehensive molecular report of naturally infected sheep with T. ovis, T. lestoquardi, T. annulata and T. luwenshuni from northern India.
绵羊泰勒虫病是热带和亚热带地区绵羊的一种重要蜱传血液原生动物病，可导致严重的生产力和经济损失。印度有关绵羊泰勒虫病分子研究的信息很少。本研究使用巢式 PCR-限制性片段长度多态性（nPCR-RFLP）鉴定了来自印度哈里亚纳邦不同农业气候区自然感染绵羊的不同泰勒虫种。在蜱虫活跃季节，从印度哈里亚纳邦的 204 只绵羊中采集血液样本和蜱虫。薄血涂片的显微镜检查显示，33.3%（68/204）的绵羊感染了泰勒虫属，而 nPCR 检测法显示 44.6%（91/204）的血液样本呈阳性。根据使用四种限制酶（Hpa II、Bsh 1285I、Hae II 和 Rsa I）的 RFLP 模式鉴定出不同的泰勒虫种。在 91 个阳性样本中，50.5%（46/91）、23.08%（21/91）、11%（10/91）和 2.2%（2/91）分别对 T.ovis、T.lestoquardi、T.luwenshuni（中国 1 号泰勒虫/中国 1 号泰勒虫）和 T.annulata 呈阳性。在 13.2%（12/91）的病例中检测到混合感染。根据 HpaII 酶消化图谱，检测到两种 T.lestoquardi 和 T.annulata、九种 T.lestoquardi 和 T.ovis 以及一种 T.ovis 和 T.annulata 的样品。通过序列分析进一步证实了这些泰勒虫种的存在。从绵羊中采集的大多数蜱虫被鉴定为 Rhipicephalus 种，其次是 Hyalomma anatolicum 和 Hemaphysalis 种。本研究首次全面报告了来自印度北部的自然感染绵羊的 T.ovis、T.lestoquardi、T.annulata 和 T.luwenshuni。
