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規(guī)模化引種場(chǎng)進(jìn)口奶牛隱孢子蟲(chóng)種類、基因亞型鑒定及其生物安全評(píng)價(jià)

2015-02-14 08:08王臣榮李俊強(qiáng)張振杰劉鵬飛余復(fù)昌曹建科寧長(zhǎng)申張龍現(xiàn)
關(guān)鍵詞:人獸孢子犢牛

王臣榮,齊 萌,李俊強(qiáng),張振杰,劉鵬飛,余復(fù)昌,曹建科,寧長(zhǎng)申,張龍現(xiàn)

規(guī)模化引種場(chǎng)進(jìn)口奶牛隱孢子蟲(chóng)種類、基因亞型鑒定及其生物安全評(píng)價(jià)

王臣榮,齊 萌,李俊強(qiáng),張振杰,劉鵬飛,余復(fù)昌,曹建科,寧長(zhǎng)申,張龍現(xiàn)

目的 為了解進(jìn)口奶牛寄生的隱孢子蟲(chóng)對(duì)引種場(chǎng)污染情況及是否影響隱孢子蟲(chóng)種類和基因型在當(dāng)?shù)氐姆植?。方?采用PCR方法檢測(cè)河南省某規(guī)?;N場(chǎng)奶牛隱孢子蟲(chóng)感染情況。結(jié)果 基于18S rRNA基因位點(diǎn)進(jìn)行PCR檢測(cè),奶牛隱孢子蟲(chóng)總感染率為17.8%(90/507),鑒定出4種隱孢子蟲(chóng),分別為微小隱孢子蟲(chóng)、牛隱孢子蟲(chóng)、芮氏隱孢子蟲(chóng)和安氏隱孢子蟲(chóng),隱孢子蟲(chóng)感染率隨牛年齡增長(zhǎng)而呈遞減趨勢(shì),差異有統(tǒng)計(jì)學(xué)意義(P<0.01)。斷奶前犢牛以微小隱孢子蟲(chóng)為優(yōu)勢(shì)感染種,斷奶前犢牛腹瀉與微小隱孢子蟲(chóng)感染呈正相關(guān)性,差異有統(tǒng)計(jì)學(xué)意義(P<0.01)?;趃p60基因位點(diǎn),43份微小隱孢子蟲(chóng)陽(yáng)性樣品成功擴(kuò)增出35份,序列分析顯示35個(gè)微小隱孢子蟲(chóng)均為人獸共患基因亞型IIdA19G1, 而奶牛引種地(澳大利亞)的牛源微小隱孢子蟲(chóng)均為IIa亞型家族存在顯著不同。結(jié)論 證實(shí)微小隱孢子蟲(chóng)為犢牛腹瀉病原之一,IId亞型為中國(guó)獨(dú)特分布的微小隱孢子蟲(chóng)亞型,其基因亞型存在地理隔離遺傳特征,引種青年牛和成年牛不影響當(dāng)?shù)刂匾双F共患蟲(chóng)種微小隱孢子蟲(chóng)基因亞型分布,從這個(gè)角度考慮不具有生物安全重要性。

隱孢子蟲(chóng);種類;基因亞型;鑒定;奶牛

隱孢子蟲(chóng)是重要的人獸共患原蟲(chóng)之一,宿主譜包括人在內(nèi)的260多種脊椎動(dòng)物,可致以腹瀉為主要臨床癥狀的隱孢子蟲(chóng)病[1]。隱孢子蟲(chóng)多通過(guò)“糞-口”途徑傳播,牛被認(rèn)為是人類隱孢子蟲(chóng)病的重要傳染源,牛糞污染水源和食物是導(dǎo)致人體隱孢子蟲(chóng)病暴發(fā)的主要因素[2-3]。寄生于牛的隱孢子蟲(chóng)主要有4種:微小隱孢子蟲(chóng)(Cryptosporidiumparvum)、安氏隱孢子蟲(chóng)(Cryptosporidiumandersoni)、牛隱孢子蟲(chóng)(Cryptosporidiumbovis)和芮氏隱孢子蟲(chóng)(Cryptosporidiumryanae)[1]。微小隱孢子蟲(chóng)是最重要的人獸共患隱孢子蟲(chóng)蟲(chóng)種,世界范圍內(nèi)人體隱孢子蟲(chóng)病例約45%由該蟲(chóng)引起,而其它3個(gè)寄生于牛的蟲(chóng)種均具有宿主特異性[1,4]。研究表明,冠狀病毒(coronavirus)、輪狀病毒(rotaviruses)、腸毒素性大腸桿菌(enterotoxicEscherichiacoli)和微小隱孢子蟲(chóng)是引起犢牛腹瀉的4個(gè)主要病原,以輪狀病毒和微小隱孢子蟲(chóng)更為常見(jiàn)[5]。

微小隱孢子蟲(chóng)具有廣泛的宿主范圍,為闡明該蟲(chóng)種動(dòng)力學(xué)傳播和人獸共患的潛在威脅性,基因亞型分析工具常用于該蟲(chóng)群體遺傳結(jié)構(gòu)鑒定和人獸共患風(fēng)險(xiǎn)評(píng)價(jià)[6-7]。研究表明,微小隱孢子蟲(chóng)群體遺傳存在較大的種內(nèi)變異,基于60-kDa 糖蛋白(gp60)基因分為IIa-i,IIk-o共14個(gè)亞型家族,其中IIa和IId亞型家族可在人和反芻動(dòng)物之間傳播,而IIc和IIe亞型家族僅通過(guò)人-人途徑傳播,其它亞型家族多具有宿主特異性[4,6,8-12]。

我國(guó)已成為世界上最大種牛進(jìn)口國(guó),2008-2013年從澳大利亞、新西蘭和烏拉圭等國(guó)進(jìn)口奶牛46萬(wàn)頭。在我國(guó)與主要進(jìn)口國(guó)雙邊簽署的動(dòng)物檢疫條款中,隱孢子蟲(chóng)未作為檢查項(xiàng)目。

1 材料方法

1.1 樣品采集 調(diào)查樣品來(lái)自河南省某規(guī)模化引種奶牛場(chǎng),該場(chǎng)于2013年4月20日從澳大利亞引進(jìn)1 000頭荷斯坦成年奶牛,采用人工授精方式進(jìn)行配種繁育。2014年6月至2014年12月對(duì)該場(chǎng)隨機(jī)經(jīng)直腸采集507頭奶牛新鮮糞便樣品,其中有腹瀉癥狀的斷奶前犢牛85頭,每份10~30 g,裝入潔凈自封袋中,記錄信息,帶回實(shí)驗(yàn)室,置4 ℃保存。奶牛年齡劃分參照中華人民共和國(guó)農(nóng)業(yè)部《奶牛標(biāo)準(zhǔn)化規(guī)模養(yǎng)殖生產(chǎn)技術(shù)規(guī)范(試行)》,<60 d為斷奶前犢牛,61~180 d為斷奶后犢牛,181~450 d為育成牛,>450 d 為成年牛。

1.2 DNA提取 取200 mg糞便樣本,用美國(guó)OMEGA Bio-Tek公司生產(chǎn)的糞便DNA提取試劑盒(E.Z.N.A.?Stool DNA Kit,D4015-02),購(gòu)于鄭州科貿(mào)生物技術(shù)有限公司,按說(shuō)明書(shū)步驟操作,提取的DNA置-20 ℃保存。

1.3 PCR擴(kuò)增 基于18S rRNA基因?qū)λ袠悠愤M(jìn)行隱孢子蟲(chóng)檢測(cè)和蟲(chóng)種鑒定,引物及反應(yīng)程序參照Xiao等[13]的方法。基于gp60基因?qū)ξ⑿‰[孢子蟲(chóng)進(jìn)行基因亞型鑒定,引物及反應(yīng)程序參照Sulaiman等[14]的方法。引物由生工生物工程(上海)股份有限公司合成。反應(yīng)體系中使用的酶為KOD-plus酶0.5 μL (日本TOYOBO公司生產(chǎn),購(gòu)于鄭州科貿(mào)生物技術(shù)有限公司),每次PCR擴(kuò)增均設(shè)陽(yáng)性對(duì)照樣品和陰性對(duì)照樣品。電泳結(jié)束后在電泳凝膠成像系統(tǒng)儀中觀察拍照。

1.4 測(cè)序 PCR產(chǎn)物測(cè)序委托北京諾賽基因有限公司完成,采用雙脫氧終止法進(jìn)行雙向測(cè)序,測(cè)序儀為ABI PRISMTM?3730 XL DNA Analyzer (Applied Biosystems,USA)。在GenBank上用Blast進(jìn)行同源序列搜索,應(yīng)用Clustal X 1.83進(jìn)行比對(duì)分析。

1.5 統(tǒng)計(jì)學(xué)分析 統(tǒng)計(jì)學(xué)分析采用χ2檢驗(yàn)。

2 結(jié) 果

2.1 隱孢子蟲(chóng)感染情況 基于18S rRNA基因位點(diǎn)對(duì)507份樣品進(jìn)行PCR擴(kuò)增和測(cè)序,90份鑒定為隱孢子蟲(chóng)陽(yáng)性,總感染率為17.8%。鑒定出4種隱孢子蟲(chóng),以微小隱孢子蟲(chóng)為優(yōu)勢(shì)感染蟲(chóng)種,所占陽(yáng)性樣品比例為47.8%,牛隱孢子蟲(chóng)、賴氏隱孢子蟲(chóng)和安氏隱孢子蟲(chóng)所占比例分別為41.1%、5.6%和5.6%。見(jiàn)表1。隱孢子蟲(chóng)感染率隨牛年齡增長(zhǎng)而呈遞減趨勢(shì),斷奶前犢牛感染率達(dá)38.8%,斷奶后犢牛、育成牛和成年牛的感染率分別為15.6%、3.8%和1.0%。見(jiàn)表1。不同年齡段奶牛隱孢子蟲(chóng)感染率差異有統(tǒng)計(jì)學(xué)意義(P<0.01)。斷奶前犢牛以微小隱孢子蟲(chóng)為優(yōu)勢(shì)感染蟲(chóng)種,斷奶后犢牛、育成牛和成年牛均以牛隱孢子蟲(chóng)為優(yōu)勢(shì)感染蟲(chóng)種。見(jiàn)表1。

2.2 不同臨床癥狀斷奶前犢牛感染情況 本次調(diào)查中,斷奶前犢牛多在7~25 d出現(xiàn)腹瀉癥狀。斷奶前腹瀉和未腹瀉犢牛隱孢子蟲(chóng)的感染率分別為44.7%和32.5%,無(wú)統(tǒng)計(jì)學(xué)差異(P>0.05)。見(jiàn)表2。斷奶前犢牛微小隱孢子蟲(chóng)為優(yōu)勢(shì)蟲(chóng)種,與腹瀉呈正相關(guān)關(guān)系,斷奶前腹瀉與未腹瀉犢牛微小隱孢子蟲(chóng)感染率差異有統(tǒng)計(jì)學(xué)意義(P<0.01)。斷奶前犢牛感染牛隱孢子蟲(chóng)與腹瀉呈負(fù)相關(guān)關(guān)系,斷奶前腹瀉與未腹瀉犢牛的牛隱孢子蟲(chóng)感染率差異有統(tǒng)計(jì)學(xué)意義(P<0.01)。見(jiàn)表2。

表1 不同年齡段奶牛隱孢子蟲(chóng)感染情況Tab.1 Infection of Cryptosporidium in dairy cattle in different age

表2 不同臨床癥狀斷奶前犢牛隱孢子蟲(chóng)感染情況Tab.2 Infection of Cryptosporidium in different clinical signs in pre-weaned calves

2.3 斷奶前犢牛隱孢子蟲(chóng)種類分布 0~7 d、8~14 d、15~21 d、22~28 d、29~35 d、36~42 d、43~49 d和50`56 d犢牛隱孢子蟲(chóng)感染分別為17.4%、66.7%、42.1%、38.5%、52.0%、29.4%、18.2%和5.6%,統(tǒng)計(jì)學(xué)差異有統(tǒng)計(jì)學(xué)意義(P<0.01)。不同周齡斷奶前犢牛隱孢子蟲(chóng)蟲(chóng)種分布存在顯著差異,僅在<35 d犢牛中發(fā)現(xiàn)微小隱孢子蟲(chóng)感染,4 d即可檢查到該蟲(chóng)感染,8~14 d 犢牛該蟲(chóng)感染率最高,為64.1%;牛隱孢子蟲(chóng)則主要感染4~7周齡犢牛,29~35 d 犢牛該蟲(chóng)感染率最高,為40.0%;芮氏隱孢子蟲(chóng)偶見(jiàn)感染4周齡后犢牛;未發(fā)現(xiàn)有C.andersoni感染。見(jiàn)圖1。

2.4 微小隱孢子蟲(chóng)基因亞型序列分析 基于gp60基因位點(diǎn)對(duì)43份微小隱孢子蟲(chóng)進(jìn)行基因亞型鑒定,成功擴(kuò)增出35條序列。經(jīng)Blast搜索和Clustal X 1.83 比對(duì),所得35條序列均與微小隱孢子基因亞型IIdA19G1(GenBank登錄號(hào):HQ009809)序列同源性為100%,該基因亞型為河南省奶牛源微小隱孢子蟲(chóng)優(yōu)勢(shì)亞型。

圖1 不同周齡斷奶前犢牛隱孢子蟲(chóng)蟲(chóng)種分布

Fig.1 Distribution ofCryptosporidiumspecies in different week ages of pre-weaned calves

3 討 論

不同國(guó)家和地區(qū),牛隱孢子蟲(chóng)病流行率存在差異較大,與其飼養(yǎng)管理、樣本數(shù)量、年齡段分布以及檢測(cè)方法等因素有關(guān)。本研究中奶牛隱孢子蟲(chóng)總感染率為17.8%,其中斷奶前犢牛感染率最高,為38.8%,高于河南省、陜西省和寧夏回族自治區(qū)斷奶前犢牛隱孢子蟲(chóng)感染率,分別為21.5%(172/801)、20.2%(52/258)和10.2%(19/186)[9,15-16],低于黑龍江省斷奶前犢牛隱孢子蟲(chóng)感染率47.7%(72/151)[17]。斷奶后犢牛感染率為15.6%,高于黑龍江省(5.5%,8/145)和河南省(11.3%,86/758)斷奶后犢牛隱孢子蟲(chóng)感染率[18-19]。在澳大利亞西部,犢牛隱孢子蟲(chóng)感染率為48%(26/54)[20],東南部新南威爾士州斷奶前犢牛隱孢子蟲(chóng)感染率為22.3%(81/364)[21]。美國(guó)一項(xiàng)調(diào)查研究顯示,<8周齡的斷奶前犢牛隱孢子蟲(chóng)感染率最高,為45.8%,依次是3~12月齡斷奶后犢牛(18.5%)和1~2歲的母牛(2.2%)[22];國(guó)內(nèi)的研究數(shù)據(jù)也顯示幼齡奶牛隱孢子蟲(chóng)感染率高于成年牛[23]。本研究結(jié)果發(fā)現(xiàn)隱孢子蟲(chóng)感染率隨牛年齡增長(zhǎng)而呈遞減趨勢(shì),與先前的國(guó)內(nèi)外報(bào)道相一致。

感染牛的隱孢子蟲(chóng)蟲(chóng)種較多,除4種自然宿主為牛的隱孢子蟲(chóng)蟲(chóng)種外,還有7種隱孢子蟲(chóng)和一個(gè)基因型可感染??苿?dòng)物[24]。本研究發(fā)現(xiàn)該引種場(chǎng)奶牛感染4種主要感染牛隱孢子蟲(chóng)蟲(chóng)種,以微小隱孢子蟲(chóng)為優(yōu)勢(shì)感染蟲(chóng)種,與大多數(shù)發(fā)達(dá)國(guó)家研究報(bào)道相一致,微小隱孢子蟲(chóng)幾乎是感染斷奶前犢牛的唯一蟲(chóng)種[4]。在中國(guó)河南省、黑龍江省和陜西省的調(diào)查結(jié)果顯示,牛隱孢子蟲(chóng)是感染斷奶前犢牛的主要蟲(chóng)種,而在寧夏回族自治區(qū)的調(diào)查結(jié)果顯示微小隱孢子蟲(chóng)是感染斷奶前犢牛的優(yōu)勢(shì)蟲(chóng)種,表明犢牛感染微小隱孢子蟲(chóng)與地理區(qū)域分布有一定關(guān)系[9,12,15-17]。同樣在澳大利亞的研究也表明犢牛感染微小隱孢子蟲(chóng)與地理分布有關(guān),在澳大利亞西部斷奶前犢牛微小隱孢子蟲(chóng)感染率為17.6%,而在維多利亞州感染率為46.3%[24]。在美國(guó)、丹麥、瑞士等國(guó)家的研究發(fā)現(xiàn),牛隱孢子蟲(chóng)是斷奶后牛主要的感染蟲(chóng)種[1,4],而在中國(guó)的大多數(shù)調(diào)查發(fā)現(xiàn)安氏隱孢子蟲(chóng)是斷奶后牛主要的感染蟲(chóng)種[19],本次調(diào)查發(fā)現(xiàn)牛隱孢子蟲(chóng)是該場(chǎng)斷奶后牛感染的優(yōu)勢(shì)蟲(chóng)種,或與該引種場(chǎng)建場(chǎng)時(shí)間較短相關(guān)。

不同的隱孢子蟲(chóng)可導(dǎo)致牛表現(xiàn)出不同的臨床癥狀,安氏隱孢子蟲(chóng)多感染青年牛和成年牛,雖不表現(xiàn)出明顯的臨床癥狀,但可引起泌乳牛產(chǎn)奶量下降[19,23]。牛隱孢子蟲(chóng)和芮氏隱孢子蟲(chóng)一般不會(huì)導(dǎo)致牛表現(xiàn)任何臨床癥狀[17,21]。微小隱孢子蟲(chóng)則主要感染斷奶前犢牛,可引起犢牛水樣腹瀉、脫水,甚至死亡[6]。犢牛腹瀉是一個(gè)復(fù)雜的,多因素的疾病,與宿主對(duì)病原體抵抗力相關(guān),微小隱孢子蟲(chóng)是最常見(jiàn)的犢牛腹瀉病原之一[5]。先前國(guó)內(nèi)有關(guān)微小隱孢子蟲(chóng)引起犢牛腹瀉的報(bào)道較少,近來(lái)在中國(guó)西北地區(qū)某奶牛場(chǎng)暴發(fā)由微小隱孢子蟲(chóng)引起的隱孢子蟲(chóng)病,犢牛群體出現(xiàn)嚴(yán)重的水樣腹瀉并導(dǎo)致死亡,調(diào)查發(fā)現(xiàn)2~3周齡的斷奶前犢牛感染率最高,達(dá)83.3%(40/48)[12]。在澳大利亞的一項(xiàng)調(diào)查顯示,斷奶前腹瀉犢牛的隱孢子蟲(chóng)感染率為73.5%(144/196),其中以微小隱孢子蟲(chóng)為主要蟲(chóng)種,所占陽(yáng)性比列為59.4%[24]。本次調(diào)查發(fā)現(xiàn),斷奶前犢牛多在7~25 d出現(xiàn)腹瀉癥狀,且主要由微小隱孢子蟲(chóng)引起。因此,應(yīng)加強(qiáng)對(duì)犢牛糞便的無(wú)害化處理,尤其是防止糞便污染水源。

牛源微小隱孢子蟲(chóng)可引起人體急性或慢性腹瀉,導(dǎo)致免疫功能低下者水樣腹瀉甚至死亡,但并非所有牛源微小隱孢子蟲(chóng)均可人獸共患[7-8]。近年來(lái),國(guó)內(nèi)有關(guān)奶牛源微小隱孢子種類和基因亞型鑒定的報(bào)道較多,基于gp60基因位點(diǎn),奶牛源微小隱孢子蟲(chóng)分離株的基因亞型均為IId亞型家族,存在人獸共患風(fēng)險(xiǎn)[9,12,17]。本研究中,35個(gè)微小隱孢子分離株的基因亞型均為IIdA19G1,與Wang等[9]報(bào)道的河南省牛源微小隱孢子分離株的基因亞型相一致。目前,在中國(guó)已有11個(gè)微小隱孢子基因亞型被鑒定,在奶牛體內(nèi)僅見(jiàn)2個(gè)IId亞型家族感染,分別為IIdA15G1和IIdA19G1。而在澳大利亞,14個(gè)奶牛源微小隱孢子蟲(chóng)基因亞型則均屬于IIa亞型家族,分別為II aA15G2R1、IIaA16G3R1、IIa-A17G2R1、IIaA18G2R1a、IIaA18G2R1b、IIaA18G3R1、IIaA18G4R1、II aA19G3R1a、IIaA19G3R1b、IIaA20G2R1、IIaA20G3R1、IIaA20G4R1、IIaA21G3R1和II aA23G3R1。微小隱孢子蟲(chóng)主要感染幼齡牛,本次調(diào)查的養(yǎng)殖場(chǎng)所引進(jìn)種牛均為成年牛,一定程度上隔離了不同微小隱孢子蟲(chóng)基因亞型的擴(kuò)散和傳播。大量群體遺傳學(xué)研究表明微小隱孢子蟲(chóng)的存在獨(dú)特的地理遺傳隔離特征[6-8],本研究結(jié)果進(jìn)一步支持微小隱孢子蟲(chóng)的基因亞型與地理分布存在明顯相關(guān)性。

國(guó)內(nèi)有關(guān)微小隱孢子蟲(chóng)對(duì)動(dòng)物致病性研究資料較少,本研究證實(shí)微小隱孢子蟲(chóng)是斷奶前犢牛腹瀉的主要病原之一,IId亞型為中國(guó)獨(dú)特分布的微小隱孢子蟲(chóng)亞型,其基因亞型存在地理隔離遺傳特征,引種青年牛和成年牛不影響當(dāng)?shù)刂匾双F共患蟲(chóng)種微小隱孢子蟲(chóng)基因亞型分布,從這個(gè)角度考慮不具有生物安全重要性,為防控隱孢子蟲(chóng)病傳播奠定了基礎(chǔ)。

[1]Ryan U, Fayer R, Xiao L.Cryptosporidiumspecies in humans and animals: current understanding and research needs[J]. Parasitology, 2014, 141(13): 1667-1685. DOI: 10.1017/S0031182014001085

[2]Blackburn BG, Mazurek JM, Hlavsa M, et al. Cryptosporidiosis associated with ozonated apple cider[J]. Emerg Infect Dis, 2006, 12(4): 684-686.

[3]Baldursson S, Karanis P. Waterborne transmission of protozoan parasites: review of worldwide outbreaks-an update 2004-2010[J]. Water Res, 2011, 45(20): 6603-6614. DOI: 10.1016/j.watres.2011.10.013

[4]Xiao L. Molecular epidemiology of cryptosporidiosis: an update[J]. Exp Parasitol, 2010, 124(1): 80-89. DOI: 10.1016/j.exppara.2009.03.018

[5]Meganck V, Hoflack G, Piepers S, et al. Evaluation of a protocol to reduce the incidence of neonatal calf diarrhoea on dairy herds[J]. Prev Vet Med, 2015, 118(1): 64-70. DOI: 10.1016/j.prevetmed.2014.11.007

[6]Wang R, Zhang L, Axen C, et al.CryptosporidiumparvumIId family: clonal population and dispersal from Western Asia to other geographical regions[J]. Sci Rep, 2014, 4: 4208. DOI: 10.1038/srep04208

[7]De Waele V, Van den Broeck F, Huyse T, et al. Panmictic structure of theCryptosporidiumparvumpopulation in irish calves: influence of prevalence and host movement[J]. Appl Environ Microbiol, 2013, 79(8): 2534-2541. DOI: 10.1128/AEM.03613-12

[8]Widmer G, Sullivan S. Genomics and population biology ofCryptosporidiumspecies[J]. Parasite Immunol,2012,34(2/3): 61-71. DOI: 10.1111/j.1365-3024.2011.01301.x

[9]Wang R, Wang H, Sun Y, et al. Characteristics ofCryptosporidiumtransmission in preweaned dairy cattle in Henan, China[J]. J Clin Microbiol, 2011, 49(3): 1077-1082. DOI: 10.1128/JCM.02194-10

[10]Amer S, Zidan S, Adamu H, et al. Prevalence and characterization ofCryptosporidiumspp. in dairy cattle in Nile River delta provinces, Egypt[J]. Exp Parasitol, 2013, 135(3): 518-523. DOI: 10.1016/j.exppara.2013.09.002

[11]Santin M. Clinical and subclinical infections withCryptosporidiumin animals[J]. N Z Vet J, 2013, 61(1): 1-10. DOI: 10.1080/00480169.2012.731681

[12]Cui Z, Wang R, Huang J, et al. Cryptosporidiosis caused byCryptosporidiumparvumsubtype IIdA15G1 at a dairy farm in Northwestern China[J]. Parasit Vectors, 2014, 7(1): 529.

[13]Xiao L, Escalante H, Yang CF, et al. Phylogenetic analysis ofCryptosporidiumparasites based on the small-subunit rRNA gene locus[J]. Appl Environ Microbiol, 1999, 65(4): 1578-1583.

[14]Sulaiman IM, Hira PR, Zhou L, et al. Unique endemicity of cryptosporidiosis in children in Kuwait[J]. J Clin Microbiol, 2005, 43(6): 2805-2809.

[15]Qi MZ, Fang YQ, Wang XT, et al. Molecular characterization ofCryptosporidiumspp. in pre-weaned calves in Shaanxi Province, Northwestern China[J]. J Med Microbiol, 2015, 64(Pt1): 111-116. DOI: 10.1099/jmm.0.079327-0

[16]Huang J, Yue D, Qi M, et al. Prevalence and molecular characterization ofCryptosporidiumspp. andGiardiaduodenalisin dairy cattle in Ningxia, northwestern China[J]. BMC Vet Res, 2014, 10(1): 292.

[17]Zhang W, Wang R, Yang F, et al. Distribution and genetic characterizations ofCryptosporidiumspp. in pre-weaned dairy calves in Northeastern China’s Heilongjiang Province[J]. PLoS One, 2013, 8(1): e54857. DOI: 10.1371/journal.pone.0054857

[18]Liu A, Wang R, Li Y, et al. Prevalence and distribution ofCryptosporidiumspp. in dairy cattle in Heilongjiang Province, China[J]. Parasitol Res, 2009, 105(3): 797-802. DOI: 10.1007/s00436-009-1457-2

[19]Wang R, Ma G, Zhao J, et al.Cryptosporidiumandersoniis the predominant species in post-weaned and adult dairy cattle in China[J]. Parasitol Int, 2011, 60(1): 1-4. DOI: 10.1016/j.parint.2010.09.002

[20]Becher KA, Robertson ID, Fraser DM, et al. Molecular epidemiology ofGiardiaandCryptosporidiuminfections in dairy calves originating from three sources in Western Australia[J]. Vet Parasitol, 2004, 123(1/2): 1-9.

[21]Ng J, Yang R, McCarthy S, et al. Molecular characterization ofCryptosporidiumandGiardiain pre-weaned calves in Western Australia and New South Wales[J]. Vet Parasitol, 2011, 176(2/3): 145-150. DOI: 10.1016/j.vetpar.2010.10.056

[22]Santin M, Trout JM, Fayer R. A longitudinal study of cryptosporidiosis in dairy cattle from birth to 2 years of age[J]. Vet Parasitol, 2008, 155(1/2): 15-23. DOI: 10.1016/j.vetpar.2008.04.018

[23]Lu QB, Qiu SX, Ru BR, et al. Identification of 5 types of Cryptosporidiosis in dairy calves in some prefectures of Henan Province[J]. Chin Vet Sci, 2008, 38(3): 261-267. (in Chinese) 盧慶斌,仇書(shū)興,茹寶瑞,等.河南省部分地區(qū)乳牛隱孢子蟲(chóng)病的流行病學(xué)調(diào)查[J].中國(guó)獸醫(yī)科學(xué),2008,38(3):261-267

[24]Ng JS, Eastwood K, Walker B, et al. Evidence ofCryptosporidiumtransmission between cattle and humans in northern New South Wales[J]. Exp Parasitol, 2012, 130(4): 437-441. DOI: 10.1016/j.exppara.2012.01.014

Species and subtype identification ofCryptosporidiumspp.from dairy cattle in an imported farm and its biosafety evaluation

WANG Chen-rong,QI Meng,LI Jun-qiang,ZHANG Zhen-jie,LIU Peng-fei,YU Fu-chang,CAO Jian-ke,NING Chang-shen,ZHANG Long-xian

(CollegeofAnimalScienceandVeterinaryMedicine,HenanAgriculturalUniversity/InternationalJointResearchLaboratoryforZoonoticDiseasesofHenanProvince,Zhengzhou450002,China)

We investigated the effect ofCryptosporidiumfrom imported cow in the local area and the distribution effect ofCryptosporidiumspecies and genotypes in the local area. Using polymerase chain reaction (PCR), we studied the infection ofCryptosporidiumfrom dairy cattle in an imported farm in Henan Province. The overall infection rate ofCryptosporidiumin dairy cattle was 17.8% (90/507) based on 18SRNA gene locus.Cryptosporidiumparvum,Cryptosporidiumbovis,CryptosporidiumryanaeandCryptosporidiumandersoniwere found. Significant differences were observed between the infection rate of sampling and age (P<0.01). The infection rate ofCryptosporidiumdecreased with age increasing in dairy cattle.Cryptosporidiumparvumwere the dominatingCryptosporidiumspp. in pre-weaning calves. We found a positively correlation between the infection ofCryptosporidiumand diarrhea of pre-weaning calves (P<0.01). Thirty-fiveCryptosporidiumparvumwere successfully amplified from 43 positive samples atgp60 gene locus, the subtype of the amplifiedCryptosporidiumparvumwere IIdA19G1, the subtype was different with IIa subtype which were found in imported country (Australia). This study confirmed thatCryptosporidiumparvumis a kind of diarrhea pathogens in dairy calves, the subtype ofCryptosporidiumparvumin China is only IId and the subtype ofCryptosporidiumparvumexist geographical isolation genetic characteristics. It does not have the importance of biological safety from the point that imported heifers and adults do not affect the distribution ofCryptosporidiumspecies and genotypes in the local area.

Cryptosporidium; species; subtype; identification; dairy cattle Support by the Key Program of the National Natural Science Foundation of China (No. 31330079), the Innovation Scientists and Technicians Troop Construction Projects of Henan Province (No. 134200510012), and the Program for Science and Technology Innovative Research Team at the University of Henan Province (No. 012IRTSTHN005)

Zhang Long-xian, Email: zhanglx8999@henau.edu.cn

國(guó)家自然科學(xué)基金重點(diǎn)項(xiàng)目(No.31330079), 河南省科技創(chuàng)新人才計(jì)劃(No.134200510012), 河南省高??蒲袆?chuàng)新團(tuán)隊(duì)項(xiàng)目(No. 012IRTSTHN005)聯(lián)合資助

張龍現(xiàn),Email: zhanglx8999@henau.edu.cn

河南農(nóng)業(yè)大學(xué)牧醫(yī)工程學(xué)院,河南省人獸共患病國(guó)際聯(lián)合實(shí)驗(yàn)室,鄭州 450002

10.3969/j.issn.1002-2694.2015.11.004

S855.9

A

1002-2694(2015)11-1005-05

2015-04-13;

2015-07-21

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