扩展莫尼茨绦虫wnt基因在虫体不同发育体节的差异表达

研究扩展莫尼茨绦虫(Moniezia expansa)wnt基因家族wnt1、wnt2、wnt4、wnt5和wnt11B5个基因在虫体不同发育体节的差异表达及组织分布规律,为进一步揭示Wnt信号通路在扩展莫尼茨绦虫发育中的作用奠定基础。作者采用SYBR GreenⅠqRT-PCR方法分析了wnt1、wnt2、wnt4、wnt5和wnt11B在虫体头颈节、幼节、成节和孕节的mRNA相对转录情况;采用核酸原位杂交方法分析上述5个基因在虫体头颈节、幼节、成节和孕节的mRNA分布情况。结果显示,wnt基因家族成员在虫体各发育体节均有表达,wnt1、wnt4、wnt5和wnt11B基因在虫体头颈节的mRNA转录水平相对较高,而在虫体孕节的mRNA转录水平最低;与之相反,wnt2基因在虫体头颈节的mRNA转录水平最低,而在虫体幼节的转录水平较高。原位杂交的结果表明,在虫体的头颈节,wnt基因主要表达于虫体的吸盘部位;在幼节和孕节,主要表达于虫体的节间腺,而在成节,wnt基因在虫体的雌雄生殖系统(如卵巢、睾丸)均有表达,并且在虫体的节间腺以及表皮也有一定的表达。综上,扩展莫尼茨绦虫5个wnt基因在虫体头颈节以及幼节的mRNA转录水平较高,且在虫体的吸盘、节间腺以及雌雄生殖细胞均有分布,因此初步推测Wnt信号通路可能参与扩展莫尼茨绦虫体节以及生殖细胞的发育过程,当然这一假说还有待进一步验证。     

科技

<正>哈兽研发现影响弓形虫生长发育重要分子近日,中国农业科学院哈尔滨兽医研究所基础免疫团队郑君博士在国际上首次证明了弓形虫翻译控制肿瘤蛋白是弓形虫快速生长及维持细胞内发育所必需的蛋白。科研人员经过系统研究,发现弓形虫强毒株翻译控制肿瘤蛋白(TCTP)的转录水平及表达量都要高于弱毒株。弓形虫TCTP的敲除明显抑制了虫体在宿主细胞内的生长和复制,而且促使未发育成熟的虫体提前逸出,从而降低了     

意大利蜜蜂工蜂幼虫饲粮中亚油酸的适宜添加水平

本试验旨在研究意大利蜜蜂工蜂幼虫饲粮中亚油酸的适宜添加水平。选取576只1日龄的工蜂幼虫,随机分为6组,每组96只幼虫,对照饲喂基础饲粮,试验组分别饲喂添加0.02%、0.04%、0.06%、0.08%和0.10%亚油酸的饲粮,试验期7 d。结果表明:1)与对照组相比,饲粮添加0.10%亚油酸显著降低了化蛹率(P0.05)。2)与对照组相比,饲粮添加0.04%亚油酸显著提高了5日龄虫体蛋白质浓度(P0.05);饲粮中添加0.10%亚油酸显著降低了7日龄蛹蛋白质浓度(P0.05)。3)与对照组相比,饲粮添加0.02%亚油酸对6日龄虫体的过氧化物酶增殖物激活受体(PPAR)α活性有显著的抑制作用(P0.05),添加0.08%的亚油酸则显著提高了6日龄虫体PPARα和PPARγ活性。4)与对照组相比,饲粮添加0.04%和0.08%亚油酸显著提高了6日龄虫体脂肪酸合成酶(FAS)活性(P0.05);添加0.08%亚油酸显著提高了5日龄虫体乙酰辅酶A羧化酶(ACC)浓度(P0.05),添加0.06%和0.10%亚油酸显著提高了6日龄虫体ACC浓度(P0.05)。5)饲料中添加本试验设定范围的亚油酸对幼虫FAS和ACC基因相对表达量无显著影响(P0.05)。综合化蛹率和虫体蛋白质浓度2个指标的拟合曲线结果,认为意大利蜜蜂工蜂幼虫饲粮中亚油酸的适宜添加水平为0.024%~0.037%。     

饲料糖水平对方格星虫稚虫生长、体组成和消化酶活性的影响

本试验旨在研究饲料糖水平对方格星虫稚虫生长、体组成和消化酶活性的影响。选取平均体重为(15.49±0.03)mg的方格星虫稚虫7 200条,随机分为6组,每组3个重复,每个重复400条。6组方格星虫稚虫分别饲喂糖水平为1.89%、7.35%、12.81%、18.27%、23.73%和29.19%的等氮等脂饲料8周。结果表明:饲料糖水平对成活率没有显著影响(P>0.05)。当饲料糖水平为1.89%～18.27%时,增重率和特定生长率随着饲料中糖水平的增加而显著上升(P<0.05),当饲料糖水平继续增加时,增重率和特定生长率则显著下降(P<0.05)。饲料糖水平对虫体粗蛋白质和粗脂肪含量有显著影响(P<0.05),对虫体水分和灰分含量没有显著影响(P>0.05)。虫体粗蛋白质含量随着饲料糖水平的增加呈先升后降的趋势,饲料糖水平为23.73%时达到最大值。虫体粗脂肪含量随着饲料糖水平的增加呈升高的趋势,饲料糖水平为29.19%时达到最大值。饲料糖水平对虫体蛋白酶和淀粉酶活性有显著影响(P<0.05),对虫体脂肪酶活性没有显著影响(P>0.05)。虫体蛋白酶和淀粉酶活性均随着饲料糖水平的增加呈先升后降的趋势,蛋白酶和淀粉酶分别在饲料糖水平为23.75%、18.27%时达到最大值。以增重率为评价指标,经回归分析得出方格星虫稚虫饲料中糖的适宜水平为18.52%。     

PCV2与PPV共感染猪外周血单个核细胞对其细胞凋亡相关因子表达水平的影响

为分析猪圆环病毒2型(PCV2)与猪细小病毒(PPV)体外共感染对猪外周血单个核细胞(PBMC)细胞凋亡相关因子mRNA转录水平的影响,探讨PCV2和PPV共感染机制及宿主—病毒之间的作用关系,运用病毒滴度和相对荧光定量PCR技术,测定和分析PCV2和PPV感染PBMC后PCV2、PPV的病毒滴度含量及Bcl-2、FasL、p53、Caspase-8、PBR、TNF-α等的转录时相变化。结果表明:PCV2、PPV能够感染PBMC细胞,PCV2/PPV共感染中PCV2、PPV的含量分别在24h显著最高(P<0.001);PCV2、PPV单独感染和PCV2与PPV共感染PBMC后引起Bcl-2、FasL、p53、Caspase-8、PBR、TNF-αmRNA转录水平上升;在3h时PCV2/PPV共感染组PBR、P53mRNA转录水平显著高于PCV2、PPV单感染组(P<0.05),12h时PCV2/PPV共感染组FasLmRNA转录水平显著高于PCV2、PPV单感染组(P<0.05),24h时Bcl-2、Caspase-8mRNA转录水平显著高于PCV2、PPV单感染组(P<0.05),PCV2/PPV共感染组TNF-αmRNA转录水平显著高于PPV组(P<0.05),与PCV2组差异不显著。结论:PCV2与PPV共感染引起细胞凋亡相关因子mRNA转录水平上调,加速淋巴细胞凋亡,本试验为PCV2和PPV共感染机制研究提供了理论基础和试验依据。     

捻转血矛线虫Hc-TTR-51蛋白的定位及功能

捻转血矛线虫(Haemonchus contortus)是最重要的家畜寄生虫之一。已报道秀丽隐杆线虫(Caenorhabditis elegans)转甲状腺素蛋白(transthyretin,TTR)参与虫体细胞间的相互作用。目前捻转血矛线虫转甲状腺素蛋白(Hc-TTR-51)的定位及功能尚未见报道。研究首先克隆捻转血矛线虫Hc-ttr-51基因,然后分析其蛋白在捻转血矛线虫、HEK 293T细胞内的定位情况,最后RNA干扰Hc-ttr-51基因分析对秀丽隐杆线虫生长发育的影响,从而对其功能进行预测分析。结果表明,捻转血矛线虫Hc-ttr-51基因在虫体各发育阶段均有表达,与其他发育期虫体相比,L1、L3、雄成虫该基因的转录水平显著上升。在L3期虫体体内该蛋白广泛表达,L4期和成虫体内该蛋白特异性表达于性腺。在HEK 293T细胞中,该蛋白在细胞质中呈明显的点状分布。RNA干扰秀丽隐杆线虫Hc-ttr-51基因表达后,虫体产卵量极显著下降,体长体宽显著缩短,咽泵率显著下降。以上研究为捻转血矛线虫生长发育特性、疫苗研究等提供依据。     

日本血吸虫七跨膜基因SjSTMP的鉴定及生物学特性分析

本实验室在扩增血吸虫Wnt信号通路Frizzled受体家族新成员过程中,获得了一个新的七跨膜蛋白(Schistosoma japonicum seven transmembrane protein,Sj STMP)的编码基因,编码含有1141个氨基酸的蛋白质。Sj STMP蛋白仅与Frizzled蛋白具有相似性,有7个穿膜区,N端也具有半胱氨酸富集区,具有作为细胞表面受体的结构基础。Sj STMP的转录随发育调节,在不同发育阶段及不同性别间Sj STMP m RNA水平存在差异,在同一发育阶段的发育正常与发育不良虫体间Sj STMP m RNA水平也存在差异。Sj STMP蛋白在虫体组织内广泛分布,无组织特异性。Sj STMP蛋白功能的进一步确定,将有助于在分子水平了解血吸虫发育调控过程。     

共轭亚油酸对奶牛乳腺上皮细胞脂肪酸摄取与转运相关基因mRNA转录的影响

为了研究共轭亚油酸(CLA)对奶牛乳腺上皮细胞脂肪酸摄取与转运相关基因mRNA转录的影响,试验采用组织块法体外培养奶牛乳腺上皮细胞,外源添加不同浓度的c9,t11-CLA与t10,c12-CLA作用乳腺上皮细胞48 h,应用实时荧光定量PCR技术,测定相关基因mRNA的转录。结果表明:1)与对照组相比,两种CLA均显著降低了脂蛋白脂肪酶(LPL)基因mRNA的表达丰度(P<0.05);2)150μmol/L c9,t11-CLA显著上调分化抗原簇36(CD36)基因mRNA的转录水平(P<0.05),其转录水平随t10,c12-CLA浓度增加显著上升(P<0.05);3)150μmol/L c9,t11-CLA和不同浓度的t10,c12-CLA均可显著上调乙酰辅酶A结合蛋白(ACBP)的转录(P<0.05);4)与对照组相比,两种CLA均显著下调脂肪酸结合蛋白3(FABP3)基因mRNA的转录水平(P<0.05)。说明两种CLA均显著下调LPL mRNA和FABP3 mRNA的转录水平,150μmol/L的两种CLA异构体上调CD36和ACBP的转录水平。     

维生素C调控肉鸡缺氧肺动脉血管平滑肌细胞缺氧诱导因子-1α mRNA转录的分子机制

作者旨在通过脯氨酸羟化酶抑制剂(DMOG)和过氧化氢(H_2O_2)刺激肉鸡缺氧肺动脉平滑肌细胞(PASMCs)探讨维生素C(VC)对其氧化还原状态与缺氧诱导因子-1α(HIF-1α)、血管内皮生长因子(VEGF)及其受体2(VEGFR2/Flk-1)mRNA转录调控的分子机制。在前期PASMCs培养和缺氧模型的基础上设计3个小试验,VC和H_2O_2、VC和DMOG、VC和H_2O_2+DMOG,每个试验5个处理,每个处理6个重复。结果表明:与常氧和缺氧空白组相比,试验1,VC显著增加SOD/MDA的比值(P0.05),显著下调HIF-1α/VEGF/VEGFR2mRNA的转录水平(P0.05),H_2O_2显著上调缺氧肉鸡PASMCs HIF-1αmRNA转录(P0.05);试验2,DMOG显著上调SOD/MDA的比值(P0.05),显著下调HIF-1α和VEGFR2mRNA转录(P0.05),但显著上调VEGF mRNA的转录(P0.05),VC+DMOG显著上调HIF-1α/VEGF/VEGFR2 mRNA转录(P0.05);试验3,VC+H_2O_2+DMOG三者同时添加极显著增加HIF-1α/VEGF/VEGFR2 mRNA转录(P0.01)。以上结果提示,VC能提升细胞外基质的抗氧化水平,其对缺氧基因表达的调控与细胞内脯氨酸羟化酶活性和氧化还原状态相关。     

猪毛尾线虫的检测及其ITS序列分析

毛尾线虫俗称鞭虫,为肠道常见寄生线虫,可感染人和多种动物。2015年11月,江西某猪场育肥猪出现腹泻症状,粪便带黏液和血液,部分病猪死亡;剖检发现猪肠道内充满了线状虫体;依据发病猪症状和虫体、虫卵的分析,初步确定该病为猪毛尾线虫病。采用通用引物扩增分离线虫的基因组内转录间隔区(internal transcribed spacer,ITS),结果显示分离虫体的ITS序列与猪毛尾线虫ITS序列的核苷酸同源性高达99.8%,从基因水平进一步证实了该病原为猪毛尾线虫;系统进化分析表明其与18条来自不同地区毛尾线虫的ITS序列相似性均93.5%,其中,与湖南益阳地区的猪毛尾线虫(AM993005)亲缘关系最近。试验结果为建立猪毛尾线虫的分子生物学诊断方法奠定了基础。     

Control of cattle mange in southern africa using ivermectin

Seven trials including 768 cattle were conducted in South Africa and Namibia to evaluate the efficacy of the systemic parasiticide ivermectin when administered subcutaneously at a dose rate of 200 micrograms/kg against sarcoptic (Sarcoptes scabiei var. bovis), chorioptic (Chorioptes bovis) and psoroptic (Psoroptes ovis var. bovis) mange mites. The efficacy of a single treatment against Psoroptes and Sarcoptes was greater than against Chorioptes. There was marked clinical cure in all treated cases with loss of crusts and hair regrowth. The number of cases of psoroptic mange in two large herds, of which 42.4% of 724 animals were clinically affected prior to mass treatment, was reduced by 99.3% following a single subcutaneous treatment with ivermectin; a single animal from which mites were recovered may not have been treated. The apparent prevalence and prospects for control and eradication of cattle mange in South Africa and Namibia are discussed.     

Comparative evaluation of two ivermectin injectable formulations against psoroptic mange in feedlot cattle

A study was carried out to compare the efficacy of two injectable formulations of ivermectin, Ivomec,(1) Merial (IVM reference) and Ivogell,(2) Intervet (IVM generic) in the treatment of psoroptic mange (Psoroptes ovis) in Charollais feedlot cattle. A total of 22 animals were ranked in order of the severity of mange and allocated to 11 replicates of 2 animals each. Within each replicate, one animal was randomly allocated to IVM reference product treatment (Group 1) and one to IVM generic (Group 2). Animals were treated on Day 0 and on Day 8 at the recommended dosage of 200 microg ivermectin/kg bodyweight. The pharmacokinetics profiles (pK) of both IVM formulations were evaluated in plasma samples taken from 6 cattle randomly chosen per group on Day 0, before treatment, and then at 6, 12, 24 hours and daily from Day 2 to Day 7 after the treatment on Day 0. Additionally, the severity of mange lesions was assessed and mites were counted in skin scrapings on Days 0, 8, 15 and 25. Animals were weighed on Day 0 and 25 and body weight and average daily gains (ADG) were evaluated. No statistical differences were found between the cattle of the two groups in any pK parameters, although the mean IVM plasma concentrations in cattle treated with the IVM reference product were consistently higher than those found in cattle treated with the generic compound. By Day 25, all animals in Group 1 had recovered clinically and parasitologically from psoroptic mange while cattle from Group 2 still had mange lesions and, in two animals, living mites were found in the skin scrapings; these differences were significant (P<0.001). The mean body weight of the two groups was significantly different on Day 25 (P<0.01) when animals in Group 1 weighed 20 kg more than those in Group 2. In conclusion, despite similarities in their pharmacokinetic profiles and formulations, the clinical efficacy of the two injectable formulations of IVM differed significantly in their therapeutic efficacy against psoroptic mange in feedlot cattle up to 25 days after treatment: this difference in response was reflected in an incomplete clinical and parasitological response in Group 2 and a slower growth rate.     

痒螨诱导宿主免疫应答研究进展

痒螨病普遍存在于世界各地,严重危害着动物的健康,也给动物养殖业造成巨大的经济损失。痒螨在宿主体表的物理活动、分泌物及其死亡后的瓦解产物,可激活宿主的一系列复杂级联反应,最终导致宿主的局部和系统性炎症反应及免疫应答。目前,国内外学者对痒螨的流行病学、治疗等方面研究较多,但在痒螨引起宿主的免疫应答方面研究相对较少。论文就动物感染痒螨后其组织和血液内炎性细胞的变化情况及痒螨诱导宿主发生的免疫应答——超敏反应、体液免疫应答和细胞免疫应答等方面进行综述。     

Field efficacy of moxidectin in dogs and rabbits naturally infested with Sarcoptes spp., Demodex spp. and Psoroptes spp. mites

The efficacy of moxidectin 1% injectable for cattle was evaluated in dogs and rabbits with naturally acquired sarcoptic, demodectic or psoroptic mites. Twenty-two dogs with generalised demodicosis were orally treated with 0.4mg/kg moxidectin daily. Forty-one dogs suffering from sarcoptic mange were treated with 0.2-0.25mg/kg moxidectin either orally or subcutaneously every week for three to six times. Seven rabbits were treated orally with 0.2mg/kg moxidectin twice 10 days apart. Of the 22 dogs with demodicosis, 14% were stopped treatment because of side effects, 14% were lost and of the remaining 72% all were cured (mean therapy duration 2.4 months). Thirty-seven of the sarcoptic mange-infected dogs finished treatment and were cured. In 17% of dogs, side effects were noted. All seven rabbits treated for psoroptic mange were cured and did not show any side effect. Our results indicate that moxidectin is effective and a good alternative for the treatment of demodicosis and scabies in dogs and psoroptic mange in rabbits. Side effects seem to occur more frequently if applied subcutaneously, therefore the oral route should be preferred.     

Eprinomectin treatment of psoroptic mange in hunter/jumper and dressage horses: a prospective, randomized, double-blinded, placebo-controlled clinical trial

The purpose of this prospective, double-blinded, placebo-controlled clinical trial was to investigate the efficacy of topical eprinomectin for the treatment of psoroptic mange infestation in horses. 24 privately owned hunter/jumper and dressage horses were diagnosed with psoroptic mange infestation based on physical findings and skin scraping results were enrolled and randomly assigned to either topical eprinomectin pour-on solution (at a dose of 500mug/kg body weight weekly once for four applications) treatment group or a placebo group (purified water). Clinical evaluations and skin scrapings were done by the same veterinary investigator at the beginning, during and at the end of the treatment. Both owners and veterinary investigator were blinded to the allocation to the groups. The efficacy of eprinomectin was assessed both clinically and parasitologically by the presence or absence of viable mites. Horses were scraped for psoroptic mites on days 7, 14, 21, 28 and 40 for follow-up. Fisher's exact test was used to assess differences between the eprinomectin treatment and placebo in the number of horses without mites (cure rates) on each assessment date. It was found that significantly fewer eprinomectin treated horses had P. equi mites detected on skin scrapings (p<0.01) than the placebo group. In conclusion, eprinomectin was effective and safe therapy against natural infestations of P. equi in the horses included in this study.     

Comparative therapeutic effect of moxidectin,doramectin and ivermectin on psoroptes mites infestation in buffalo (<Emphasis Type="Italic">Bubalus bubalis</Emphasis>)

The aim of the present study was to carry out comparative therapeutic effect of moxidectin pour on, doramectin and ivermectin on psoroptes infestation in buffalo. A total of 318 buffalo in 77 small scale herds suspected to have mange mites were examined clinically and parasitologically. Fifty-three (16.66%) buffalo in 25 herds were recorded to be infested; 51 (16.35%) with psoroptic mites, and two (0.31%) with chorioptic mites. Buffalo with psoroptic mites were randomly allocated into three groups (17 buffalo each). First group was treated with moxidectin pour on at a dose rate of 0.5 mg kg^-1. The second group received doramectin (200 μg kg^-1 twice subcutaneously, 14 days apart). The third group received ivermectin (200 μg kg^-1 twice subcutaneously, 14 days apart). Adjunct to each drug, deltamethrin was applied to the surrounding environment twice at a two week interval. Treatment outcomes of 51 buffalo with psoroptic mites showed that moxidectin pour on and doramectin had a significant higher effect on mite count reduction (MANOVA, P < 0.01; Walks^, Lambda, P < 0.01) and clinical sum scores (MANOVA, P < 0.05; Walks^, Lambda, P < 0.05) compared with injectible ivermectin. On clinical level, the number of clinically recovered buffalo in moxidectin and doramectin treated groups was significantly (P < 0.05) higher than that of ivermectin treated group. The result of the present study indicated that psoroptic mites are the main cause of mange in buffalo in Lower Egypt. This is the first report that describes the effect of moxidectin in buffalo. Moxidectin is a good alternative and easily applied drug for treatment of psoroptes infestation in buffalo.     

19种植物提取物的杀螨活性观察

通过体外杀虫试验观察了百部等 19种植物甲醇粗提物对兔痒螨的杀灭活性。结果表明含原植物 5 0 %的百部、橘皮、白鲜皮、苦楝皮、苦参、打破碗花花和博落回等 7种植物甲醇粗提物的水悬液均可在 4h内杀灭兔痒螨成虫 ,其中百部与博落回可在 2h内杀灭痒螨 ,其活性不低于2mg/L的阿维菌素水溶液     

Diagnosis of psoroptic sheep scab with an improved enzyme-linked immunosorbent assay

An enzyme-linked immunosorbent assay (ELISA) was developed for the detection of specific antibodies against crude Psoroptes antigen. The diagnostic sensitivity was 93.7% in 191 sheep with clinical signs associated with mange. These animals originated from 29 flocks in which psoroptic mites were detected. All of 59 sheep infested with Psoroptes ovis were seropositive. Additionally, in 49% of 70 clinically unaffected sheep originating from P. ovis-infested flocks, specific antibodies could be detected, suggesting that asymptomatic infestations can be diagnosed by serology. The specificity of the ELISA was 96.5% as determined with 254 sheep originating from 44 flocks without clinical mange. Cross-reactivity in a low range was detected with selected sera of sheep with clinical chorioptic or forage mite infestations. Four sheep seroconverted 2 weeks after experimental P. ovis infestation, i.e. 2 weeks before clinical signs became obvious. After successful doramectin treatment of 14 sheep with naturally acquired P. ovis infestation, the ELISA values declined slowly but remained positive in seven cases beyond 17 weeks.     

Ivermectin as an antiparasitic agent in cattle

In experimental trials on cattle, ivermectin given SC at 200 micrograms/kg had 95% or better efficacy against adult and immature GI and pulmonary nematodes, including inhibited fourth-stage larvae of Ostertagia ostertagi. Studies of efficacy against ectoparasites revealed nearly 100% efficacy against sucking lice, psoroptic and sarcoptic mange mites and cattle grubs. Safety trials revealed no adverse effects with the recommended dosage, including bulls and pregnant cows. A few grub-infested cattle died from acute esophagitis associated with a host-parasite reaction after ivermectin injection.     

Efficacy of topical administration of eprinomectin for treatment of ear mite infestation in six rabbits

Six rabbits naturally infested with Psoroptes cuniculi were treated topically on the skin at the base of the neck with 0.5 mg kg(-1) of 0.5% pour-on eprinomectin for cattle, twice at 14-day intervals. Efficacy of the drug was based on the disappearance of clinical signs and the absence of live mites for a period of 6 weeks. Clinical improvement was seen within 3 days of the first application; however, complete recovery of clinical signs and elimination of mites in 5/6 rabbits did not occur until the end of the study. No adverse reactions attributable to eprinomectin treatment were observed during the observation period. Results of this trial indicated that eprinomectin was partially effective in the treatment of psoroptic mange in rabbits.