甘肃省河西区域牛羊梨形虫病病原及媒介蜱分子流行病学调查

巴贝斯虫（Babesia spp.）和泰勒虫（Theileria spp.）是世界范围内流行的蜱传播梨形虫病病原体。为评价梨形虫病传播情况,为甘肃省河西区域梨形虫病防治提供流行病学资料,采集该区域部分县区的牛羊抗凝血样品和环境游离蜱虫进行梨形虫病病原检测,分析样品中病原体的存在和分布情况,利用MEGA 6.06软件和NCBI GenBank数据库的BLASTn工具,对阳性样品中的巴贝斯虫和泰勒虫18S rRNA基因进行序列分析和遗传进化树构建。通过基于18S rRNA的巢氏PCR方法,检出梨形虫病病原1目2科9种,包括莫氏巴贝斯虫、双芽巴贝斯虫和隐藏巴贝斯虫3种巴贝斯虫,东方泰勒虫、中华泰勒虫、分离泰勒虫、吕氏泰勒虫、狍泰勒虫和环形泰勒虫6种泰勒虫。牛羊抗凝血样品梨形虫病病原总感染率为8.84%（16/181）,阳性样品分布于武威市（感染率14.94%）和张掖市（感染率3.45%）;检出携带梨形虫病病原的蜱9只,蜱病原携带率为2.52%（9/357）。检出的梨形虫病病原分属泰勒虫属和巴贝斯虫属2大类,每种病原跟国内外检出虫株的同源性均较高,处于各虫株相应分支上,提交序列相似率达99%～...     

四川省攀西地区羊梨形虫的分子流行病学调查

为了解四川省攀西地区羊梨形虫的感染情况及种类分布,本研究采用原虫、泰勒虫18S r RNA基因通用引物和种特异性引物对采集自凉山州和攀枝花市7个县/市的497份羊血样样品进行套式PCR检测,并对阳性样品进行测序和序列分析。结果显示,攀西地区7个县/市羊梨形虫阳性率为11.27%(56/497),其中吕氏泰勒虫、尤氏泰勒虫阳性率分别为10.46%(52/497)、0.20%(1/497),混合感染率为0.20%(1/497),未检出绵羊泰勒虫。分歧巴贝斯虫和Babesia sp.KO1阳性率分别为0.20%(1/497)和0.80%(4/497),Babesia sp.KO1与吕氏泰勒虫混合感染率为0.20%(1/497),未检出莫氏巴贝斯虫和羊巴贝斯虫。山羊和绵羊梨形虫阳性率分别为10.35%(47/454)和20.93%(9/43)。经卡方检验,西昌市、布拖县、会理县和米易县梨形虫阳性率均与美姑县、普格县和盐边县差异显著(p0.05),山羊与绵羊梨形虫阳性率也差异显著(p0.05)。本研究结果表明攀西地区存在羊梨形虫的感染,且以单一病原感染为主,其中吕氏泰勒虫为主要虫种,该地区应加强对羊梨形虫病的防控。     

羊梨形虫分子分类遗传标记的研究进展

正羊梨形虫(piroplasms)隶属于顶复门(Apicom-plexa)、孢子虫纲(Sporozoea)、梨形虫亚纲(Piro-plasmia)、巴贝斯科(Babesiidae)巴贝斯属(Babesia)和泰勒科(Theileriidae)泰勒属(Theileria)[1]。目前,国内外已报道感染羊的巴贝斯虫主要有莫氏巴贝斯     

牛梨形虫病的诊治

<正>牛梨形虫病是巴贝斯科和泰勒科的各种梨形虫在牛血液内引起的疾病的总称,本病是一种季节性的由蜱传播的血液原虫病,杂种牛、外来纯种牛易感性高,病情重,死亡率高。迄今为止,全世界已记载的各种哺乳动物的巴贝斯虫有67种,泰勒虫有13种。在我国的马、牛、羊、犬中,已发现8种巴贝斯虫和4种泰勒虫。我国牛梨形虫主要有双芽巴贝斯虫、牛巴贝斯虫、环形泰勒虫和瑟氏泰勒虫4种。2003年至2005年,我们诊治辽宁省锦州市周边地区牛梨形虫病213例,由于诊治及时、措施得当,仅死亡2头,死亡率为0.94%,其余均已治愈,现将诊治情况介绍如下。     

新疆部分地区牛梨形虫和无浆体感染情况调查分析

为了解新疆吐鲁番与阿勒泰地区牛梨形虫及牛无浆体的感染率和种类,采用聚合酶链反应(PCR)技术对两地区随机采集的120份牛血样品进行了泰勒虫、巴贝斯虫及无浆体的病原检测,对感染率进行统计学分析,并对其系统发育进行分析。结果显示,牛环形泰勒虫、牛双芽巴贝斯虫及牛无浆体感染率分别为20.8%(25/120)、14.2%(17/120)和11.7%(14/120),其中28头牛感染2种～3种病原,呈混合感染。调查结果可为上述两地区泰勒虫病、巴贝斯虫病及无浆体虫病防控提供参考。     

广西部分地区牛和羊梨形虫流行情况调查及鉴定

为了解广西牛、羊群感染梨形虫情况,以及种类分布,从广西南宁、柳州、百色、河池、贺州等地区牛、羊养殖场采集抗凝血638份,抽提血液DNA组,运用套式PCR方法对梨形虫的18S rRNA进行扩增,并抽取一部分阳性样品进行测序,构建系统发育树。结果显示,5个地区梨形虫平均感染为24.76%,其中牛平均感染率为34.30%,羊平均感染为20.19%。南宁、河池、百色等地区牛平均感染率分别为40.00%、43.24%和23.86%;南宁、柳州、河池、百色、贺州等地区羊平均感染率为0、55.34%、11.48%、4.24%和23.40%。序列对比后涉及的种类有双芽巴贝斯虫、牛巴贝斯虫、环形泰勒虫、东方泰勒虫、吕氏泰勒虫,其中东方泰勒虫、吕氏泰勒虫是优势种。获得的序列与系统发育树中所有参考的种类进化树均在同一个分支上。结果表明,广西5个地区牛、羊梨形虫感染率较高,涉及5个种类,在日常监测和防治牛、羊寄生虫病中应引起足够重视。     

牛梨形虫病的诊断与防治

牛梨形虫是对牛危害较大的血液寄生虫,侵袭牛的梨形虫主要是牛双芽巴贝斯焦虫（Babesia bigemina）、牛巴贝斯焦虫（B．bovis）和牛泰勒焦虫（T.annulata）。牛梨形虫病是由牛梨形虫感染而引起的一种需经硬蜱传播的血液寄生虫病。据有关资料表明,在亚洲、欧洲大部分地区都有此病,我国主要发生于西部及南方各省,是一种世界性的血液原虫病。     

新疆和静县和吐鲁番地区牛感染巴贝斯虫病的血清学调查

为了解双芽巴贝斯虫和牛巴贝斯虫在新疆疫区牛感染的状况,从吐鲁番市周边散养户、和静县部分散养户采集了273份牛(牦牛)血清。采用间接ELISA方法对血清样本进行牛巴贝斯虫和双芽巴贝斯虫抗体检测。结果显示:和静县部分散养户被检牦牛血清抗牛巴贝斯虫(B.bovis)抗体阳性率为18.68%(17/91);被检牦牛血清抗双芽巴贝斯虫(B.bigemina)抗体阳性率为9.89%(9/91)。吐鲁番市周边散养户被检奶牛血清抗牛巴贝斯虫(B.bovis)抗体阳性率为15.38%(28/182);被检奶牛血清抗双芽巴贝斯虫(B.bigemina)抗体阳性率为9.34%(17/182)。通过调查发现牛巴贝斯虫和双芽巴贝斯虫均有混合感染的现象,其中和静牦牛混合感染率为6.59%(6/91);吐鲁番奶牛混合感染率为8.24%(15/182);不同品种牛均可感染牛巴贝斯虫和双芽巴贝斯虫,其感染程度及感染率具有一定的差异。本次试验结果可为有效防治新疆疫区牛梨形虫病提供重要依据。     

湖南省部分奶牛场梨形虫病感染情况调查

为了解奶牛梨形虫感染情况，从湖南省长沙等地5个奶牛场中抽检356头牛，检出有梨形虫牛187头，感染率为52.5％，包括双芽巴贝斯、牛巴贝斯、环形泰勒和瑟氏泰勒等4种，该病危害各年龄段的牛，以1～2岁牛感染率较高；发病症状表现明显，妊娠母牛出现流产；呈暴发性流行。对我省奶牛养殖业危害甚大。     

奶牛梨形虫病的诊治

奶牛梨形虫病,也称焦虫病,主要由牛双芽巴贝斯虫、牛巴贝斯虫和牛环形泰勒梨形虫引起的寄生虫疾病。牛双芽巴贝斯虫寄生在红细胞内,而牛环形泰勒梨形虫则寄生在红细胞和网状系统内。     

Heartworm in dogs in Canada in 1985

In late December 1985, 1485 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1985 and 44% of them responded. Veterinarians reported that 137,300 dogs were blood-tested to check for microfilariae and 1210 dogs were found with heartworm. Another 36 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number diagnosed in 1985 as 1247 (0.91%).

Heartworm was reported from all provinces except Prince Edward Island, Newfoundland and Saskatchewan but most (1126) of the cases were in Ontario. Southwestern Ontario continued to be the primary focus of the infection in Canada. From Quebec, 91 cases were reported mostly from and around Montreal. From Manitoba, 19 cases were reported from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 28% of the cases were observed with clinical signs of heartworm disease and 78% had a history of not having left Canada.

     

Heartworm in dogs in Canada in 1988

In late November 1988, 1581 small and mixed animal clinics and institutional veterinarians across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1988, and 46% of them responded. Veterinarians reported that 181,577 dogs were blood-tested for heartworm disease and 367 dogs were found with D. immitis microfilariae. Another 60 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1988 as 441 (0.24%).     

Heartworm in dogs in Canada in 1984

In late December 1984, 1853 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1984 and 35% of them responded. Veterinarians reported that 97,794 dogs were blood-tested to check for microfilariae and 1417 dogs (1.45% of those tested) were found with heartworm. Another 34 dogs were amicrofilaremic, but were diagnosed as having heartworm disease, to give the total number diagnosed in 1984 as 1451 (1.48%). Heartworm was reported from all provinces except Prince Edward Island and Newfoundland but most (1310) of the cases were in Ontario. In Quebec, 126 cases were reported mostly from west of Montreal.

Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 27% of the cases were observed with clinical signs of heartworm disease and 72% had a history of not having left Canada. Southwestern Ontario continued to be the primary focus of the infection.

     

Heartworm in dogs in Canada in 1991

In late November 1991, 1883 clinics in Canada were sent a questionnaire to assess the status of Dirofilaria immitis in dogs in 1991 and there was a 60.0% response. There were 344,031 dogs tested for heart-worm (HW), 627 were found infected and the prevalence of HW infection was 0.18%. There were 417 dogs with HW in Ontario, 116 in Manitoba, 38 in Quebec, 53 in British Columbia, three in Alberta, and one in Nova Scotia. In British Columbia, all of the infected dogs but one were from the Okanagan valley which, as from 1991, is a new focus of infection in Canada. Most dogs with HW had not been on preventive medication in 1990, and the prevalence among dogs tested and unprotected was 0.59%. That prevalence was considerably higher in endemic areas. Companion dogs, over three years of age and maintained primarily outdoors in rural areas, were most frequently infected. One cat was diagnosed with D. immitis and 33 dogs had Dipetalonema reconditium.     

Heartworm in dogs in Canada in 1989

In late November 1989, 1732 clinics and institutional veterinarians were sent a questionnaire to assess the status of Dirofilaria immitis, and 51.7% responded. Of 247,716 dogs tested, 394 had D. immitis microfilariae and 51 were amicrofilaremic for a total of 445 cases and heartworm prevalence of 0.17%. Most (408) of these dogs had no preventive medication and the prevalence among dogs tested and unprotected was 1.01%. That prevalence was considerably higher in endemic areas. Thirty-seven dogs with heartworm had preventive medication. Heartworm was most frequent in companion dogs over three years of age maintained outdoors in rural areas. About 75% of the cases had never left Canada, 26% had clinical signs and 125 were not treated.

Heartworm was reported from British Columbia, Manitoba, Ontario, Quebec, Nova Scotia and Newfoundland, but 383 cases were in Ontario. South-western Ontario was the primary focus of infection. There were 33 cases in Quebec and 24 in Manitoba, mainly found in and around Metropolitan Montreal and Winnipeg respectively.

     

Heartworm in dogs in Canada in 1987

In late November 1987, 1246 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1987, and 50% of them responded. Veterinarians reported that 165,428 dogs were blood tested for heartworm disease and 511 dogs were found with D. immitis microfilariae. Another 78 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1987 as 589 (0.35%).     

Heartworm in dogs in Canada in 1986

In late December 1986, 1224 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1986; 46% of them responded. Veterinarians reported that 150,989 dogs were blood-tested for microfilariae and 869 dogs were found with heartworm. Another 65 dogs were amicrofilaremic but diagnosed with heartworm disease and one was found with heartworm at necropsy to give the total number diagnosed in 1986 as 935 (0.62%).

Heartworm was reported from Manitoba, New Brunswick, Ontario and Quebec, but most (810) of the cases were from Ontario. South-western Ontario continued to be the primary focus of the infection in Canada. There were 103 cases reported from Quebec, mostly from and around Montreal, and 21 cases from Manitoba, from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 33% of the cases were observed with clinical signs of heartworm disease and 81% had a history of not having left Canada.

     

Heartworm in dogs in Canada in 1983

In late December 1983, 2 800 veterinarians across Canada were sent a questionnaire in order to assess the status of heartworm disease in Canada in 1983 and 26% of them responded. Veterinarians reported that 59 504 dogs were blood-tested to check for microfilariae and 771 dogs (1.30% of those tested) were found with Dirofilaria immitis. Heartworm disease was diagnosed in all provinces except New Brunswick and Newfoundland but most (733) of the cases were in Ontario.

Heartworm disease was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 31% of the cases were observed with clinical signs of heartworm disease and 64% had a history of not having left Canada. Southwestern Ontario continues to be the focus of the infection and most of the dogs there had not left the province previously.