动物痒螨病的免疫学研究进展

痒螨病主要是由痒螨科(psoroptidae)痒螨属(psoroptes)的痒螨(p sorop tes commun is)寄生于哺乳动物的皮肤表面,以刺吸宿主的体液、淋巴液和渗出液为营养,引起患病动物的一种慢性、顽固性、接触性、传染性皮肤病。该病以季节性发生和剧烈的皮肤瘙痒、炎症、脱毛、消瘦为特征,通过直接接触或间接接触传播。痒螨不仅可侵害马、牛、羊、兔等家畜,也可侵害鹿、骆驼、狐、貂、大熊猫等野生动物。痒螨病流行范围很广,呈世界性分布。该病严重危害着动物生产和人畜健康,可致动物个体或大群死亡,但更多的则是影响机体生产性能和动物产品质量,增加饲…     

宿主对绦虫蚴感染免疫应答的研究进展

从绦虫蚴病的细胞免疫及细胞因子、体液免疫、补体介导的免疫应答、绦虫蚴分泌物对宿主反应的抑制几方面阐述了宿主对绦虫蚴感染免疫应答的研究进展。旨在探讨绦虫蚴感染宿主后不同发育阶段细胞免疫和体液免疫的特点、绦虫蚴产生的活性分子MF对宿主免疫应答的调节以及宿主产生的NO和补体对感染绦虫蚴的抑制和杀灭作用。     

口蹄疫病毒致病性及抗原变异研究进展

口蹄疫病毒（Foot-and-mouth disease virus,FMDV）可以感染各种偶蹄动物,出现不同严重程度的临床症状。虽然近年来在口蹄疫病毒的复制、细胞识别、病毒结构-功能之间的关系等研究方面取得重要进展,但对病毒的致病机理仍然不完全清楚,对病毒的致病性、毒力因子与宿主细胞受体等的相互作用以及宿主对感染或免疫接种应答的免疫生物学的认识,对病毒抗原变异,逃避宿主的体液或细胞免疫应答反应,造成病毒的持续感染机理有待进一步深入研究。     

正痘病毒干扰宿主免疫应答的分子及其作用途径

正痘病毒属的牛痘病毒、痘苗病毒以及猴痘病毒等成员是最重要的动物源性人兽共患病病原.作者围绕这些正痘病毒编码的干扰宿主免疫应答的分子及其作用途径,重点介绍了病毒阻断宿主干扰素反应、抑制宿主TNF诱导的反应以及失活宿主防御反应的免疫成分等策略,以加深对痘病毒感染的宿主特异性、免疫逃避以及致病的分子机制的理解.     

毛兔疥癣病的药物防治研究

兔螨虫病主要有疥螨病和痒螨病两类。由疥螨引起的疾病叫兔子疥螨病,也叫兔疥癣。螨虫寄生于兔,不但钻进宿主表皮挖凿隧道,损坏皮质,引起兔子骚痒不安、兔毛脱落,而且吸取动物体液,夺走营养,影响动物生长发育,甚至破坏机体免疫屏障,继发其它疾病而死亡,造成重大的经济损失。 为了减少螨病对兔子的危害,克服疥癣病无良药之状况,我们用螨立克对毛兔疥螨病进行临床药物防治研究。现报告如下。 一、材料与方法 1、试验药物:选用经实验室试验筛选出来的“螨立克”,由浙江省农科院畜牧兽医研究所配制供应。     

新城疫病毒免疫逃逸的机制研究

新城疫(Newcastle disease)是由新城疫病毒(Newcastle disease virus,NDV)感染大多数禽类,以发生呼吸困难、头冠紫黑和下痢等症状的一种急性、高度接触性传染病。该病一年四季均可发生,但以冬季最为严重,不同曰龄鸡均可感染。被世界动物卫生组织(OIE)列为法定报告的动物疫病之一。对禽类养殖业危害较大。NDV属单股负链RNA病毒目、副黏病毒科、副黏病毒亚科、胳腺炎病毒属的禽副黏病毒。在NDV感染宿主后,病毒可以产生一系列反应以应对宿主的免疫应答以利于自己的病毒复制,起到免疫逃避的作用。NDV免疫逃避机制主要通过抑制与干扰素相关反应、抑制细胞凋亡以及利用宿主真核翻译系统逃逸宿主免疫反应等途径实现。     

病毒免疫逃逸防卫机制

从各种各样的病毒免疫逃逸机制中归纳概括出病毒逃避宿主抗感染反应的三个大方面,包括病毒逃避体液免疫系统的识别、病毒抑制细胞免疫应答以及病毒干扰免疫效应功能,以期为研制新的病毒疫苗和抗病毒药物提供参考。在宿主和病毒的长期共同进化过程中,宿主发展了各种免疫机制以清除病毒,而病毒则进化出各种免疫逃逸机制来躲避宿主的免疫应答。     

丁酸介导下肠道菌群与宿主免疫互作机制的研究进展

肠道菌群或其代谢产物在动物机体生长发育与功能完善方面起重要作用,当宿主与肠道菌群间的动态平衡被打破,可诱发局部或全身性炎症反应。丁酸不仅作为能源物质为机体提供能量,还能调控宿主先天性免疫和适应性免疫状态,促进机体免疫应答;并影响宿主分泌抗菌肽（AMPs）等预防肠道病原菌易位,维持肠道菌群的稳态。本文将系统介绍丁酸介导下肠道菌群与宿主免疫系统间互作机制的研究进展,并阐明其在肠道健康稳态中的重要作用。     

新孢子虫病免疫预防研究进展

新孢子虫病是由犬新孢子虫引起的一种原虫病,给养殖业带来严重经济损失。然而因对新孢子虫病的研究起步较晚且认识较浅,对该病的防制手段较为有限。随着对新孢子虫介导宿主免疫应答反应及虫体抗原等多方面的研究不断深入,新孢子虫病的疫苗研制不断取得进步。本研究从宿主抗新孢子虫感染的免疫应答及其在疫苗研制的应用方面进行概述,以期为新孢子虫病疫苗的研制提供参考。     

病毒干扰抗原递呈途径和细胞杀伤作用的研究进展

从病毒干扰宿主免疫细胞对病毒抗原的摄取、递呈和杀伤等方面阐述了病毒抗感染免疫应答的研究进展。探讨了病毒感染宿主后，病毒对机体细胞免疫应答的抑制、对各种免疫杀伤细胞功能的阻断以及在宿主体内延续感染的机制。     

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.     

Effect of ivermectin in heifers on mortality and egg production of Psoroptes ovis

Ten stanchioned heifers, heavily infested with Psoroptes ovis (Hering), were each given a single subcutaneous injection of 200 micrograms of ivermectin/kg. Another 10 heavily infested heifers (stanchioned) were injected subcutaneously with the solvent system (vehicle) used to formulate the ivermectin. Treatment with the vehicle did not reduce mite populations or total egg counts. The 10 heifers treated with ivermectin had an immediate reduction in live mite and egg counts (an increase in the percentage of mortality of mites) and were completely free of psoroptic mites by 20 days after treatment. Ivermectin was equally effective against adult and immature psoroptic mites.     

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 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.     

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.     

Subversion and piracy: DNA viruses and immune evasion

During the co-evolution of viruses with their vertebrate hosts, the DNA viruses have acquired an impressive array of immunomodulatory genes to combat host immune responses and their hosts have developed a sophisticated immune system to contain virus infections. In order to replicate, the viruses have evolved mechanisms to inhibit key host anti-virus responses that include apoptosis, interferon production, chemokine production, inflammatory cytokine production, and the activity of cytotoxic T-cells, natural killer cells and antibody. In addition, some of the viruses encode cytokine or chemokine homologues that recruit or expand cell numbers for infection or that subvert the host cellular response from a protective response to a benign one. The specificity of the viral immunomodulatory molecules reflects the life cycle and the pathogenesis of the viruses. Herpesviruses achieve latency in host cells by inducing cell survival and protecting infected cells from immune recognition. This involves interference with cell signal transduction pathways. Many of the viral immunomodulatory proteins are homologues of host proteins that appear to have been pirated from the host and reassorted in the virus genomes. Some of these have unique functions and indicate novel or important aspects of both viral pathogenesis and host immunity to viruses. The specific example of orf virus infection of sheep is described.     

Risk factors of infestation by Psoroptes spp. mites in buffalo (Bubalus bubalis) at smallholder farms in the Nile Delta region, Egypt

The aim of the present study was to explore the prevalence and potential risk factors associated with infestation by Psoroptes spp. mites in buffalo at smallholder farms in the Nile Delta region, Egypt. A total of 318 out of 1234 buffalo in 77 small scale herds were examined. The age of buffalo varied from three months to seven years. In all, 53 (16.66%) buffalo were recorded to be infested; 51 (16.35%) with Psoroptes spp. mites and two cases (0.31%) with Chorioptes spp. mites. Multivariate logistic regression was performed for significant risk factors at univariate analysis on both animal and herd level. The results of multivariate analysis showed that, on the animal level, the prevalence was affected by animal age (P?<?0.01; OR: 0.71; CI 95%: 0.441–1.11), season (P?<?0.01; OR: 1.20; CI 95%:0.541–1.15), indoor management (P?<?0.001; OR: 6.625; CI 95%:2.489 –17.631) and rearing with other animals (P?<?0.01; OR: 2.22; CI 95%:1.340 –7.132). However, on the herd level, the prevalence was affected by indoor rearing (P?<?0.05; OR: 22.4; CI 95%:2.75–16.431), mixed rearing with other animal species (P?<?0.05; OR: 4.5; CI 95%:1.66–7.941), and season (P?<?0.01; OR: 2.3; CI 95%:0.575–2.426). Clinically, mild skin lesions with mild pruritis were significantly prevalent in buffalo with the infestation by Psoroptes spp. mites (P?<?0.001), where 33/51 cases showed mild lesions. Also, psoroptic mites had significant association with inappitence (P?<?0.001). The result of the present study indicates that Psoroptes spp. mites are the most prevalent in buffalo in the Nile Delta Region, Egypt. Moreover, recognition of risk factors associated with mange mites in buffalo may enable the practitioner to establish the most appropriate control measures.     

绵羊痒螨兔亚种MMP2基因的转录水平及其重组蛋白间接ELISA的建立

本研究旨在分析绵羊痒螨兔亚种MMP2基因(PocMMP2)的虫体转录水平,及建立针对重组PocMMP2(rPocMMP2)蛋白抗体的间接ELISA检测方法(iELISA).通过实时荧光定量PCR(qRT-PCR)测定PocMMP2在不同发育阶段虫体、饱食与饥饿虫体的转录水平,采用原核表达系统获得rPocMMP2,经方阵...     

The infectivity of surviving Psoroptes ovis (Hering) on cattle treated with ivermectin

Ivermectin, 22,23-dihydroavermectin B1 (Merck MK-933), injected intramuscularly at the rate of 200 microgram kg-1 body wt., completely eliminated Psoroptes ovis populations from 6 Hereford cattle within 2 weeks after treatment. However, mites surviving 1, 3, and 5 days after treatment were viable and infective when transferred to untreated cattle. Mites surviving 7 days after treatment did not cause scabies or establish a colony of mites when transferred to untreated cattle. These results indicate that cattle treated with ivermectin for control of psoroptic scabies should be isolated from other cattle for at least 5 days after treatment.     

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.