规模化猪场暴发附红细胞体病的诊治

附红细胞体病是由猪附红细胞体Eperythrozoonsuis引起的一种以黄疸和贫血为主要特征的传染病,又称之为猪赤兽体病,也有人曾以黄疸性贫血病、类边虫病和红皮病等名称描述过。一般呈隐性感染,多在有应激因素时发病;主要表现为急性发热、贫血性黄疸、精神不振、食欲减退或废绝、四肢乏力、结膜苍白或黄染、妊娠母猪流产、产死胎为特征。病原主要分布于血液红细胞边缘或血浆中,该病原体呈球形、卵圆形、逗点形、杆状等多形性,大小为0.3～1.3×0.5～2.6μm。病原体常单个、数个甚至10多个寄生于红细胞中央或边缘。病原对宿主特异性强,该病原体对…     

一例猪瘟与圆环病毒2型混合感染的诊治

在生猪养殖过程中,其受到多种病原混合感染的情况较为常见,这种混合感染也容易导致传统的临床诊断的误诊或漏诊,继而延误猪场疾病的治疗,造成巨大的经历损失。2020年8月初,云南省昆明市某养殖场突发疑似猪瘟(CSF)疫情,猪群临床主要表现为呼吸困难、高热,病理变化为肾脏出血,脾脏边缘梗死等,且回盲瓣纽扣状溃疡。实验室诊断结果表明,该场疫情由猪瘟病毒(CSFV)与猪圆环病毒2型(PCV2)混合感染所致,经过针对性治疗与防控,该场猪群恢复健康。     

规模化猪场增强药物消毒效果的技术措施

正消毒是控制外界病原微生物的侵入、扩散及场内猪群病原微生物的扩散,是维持或提高猪群健康水平的重要手段之一。养殖场必须做好消毒药的选择,配制,保存和使用,同时更重要的是要建立起来一个制度去规范消毒行为和消毒结果。规模化猪场的生产中,疫病的发生往往是多因素综合作用的结果,但     

猪场圆环病毒2型感染的思考

<正>猪圆环病毒2型(Porcinecircov-ius2,PCV2)是最近几年新发现的一种严重威胁养猪业的病毒。自90年代以来,PCV2及与其有关的疾病已经给全球养猪业造成了巨大的经济损失。我     

河南省某规模化猪场高致病性蓝耳病的诊断与防制

通过临床症状、大体病理变化,流行调查及病毒分离和鉴定以及血清学检测,确定河南焦作某猪场发生的疫情为高致病性猪蓝耳病(HP-PRRS),通过加强管理,提高环境温度并减小昼夜温差,提高营养水平;采取中西药结合的综合性治疗技术措施使育肥猪成活率达到93.35%,保育猪成活率达到100%,取得显著的治疗效果。由此说明猪发病后及时诊断,尽快采取有效的防控措施是减少死亡的重要保证。     

某规模化猪场暴发猪丹毒病的综合诊治与思考

正猪丹毒丝菌俗称猪丹毒杆菌或丹毒丝菌,属丹毒丝菌属(Erysipelothrix),是一种兼性,无芽孢形成的,非抗酸性,革兰氏阳性小杆菌。在十九世纪末期,丹毒丝菌被公认为是人类致病菌,能够广泛的、长时期的存在于环境当中,包括在海洋中,其可与种类繁多的野生和家养动物、鸟类和鱼类共生或使它们发病。猪丹毒丝菌可以导致猪丹毒,是一种可以广泛流行的、能够造     

规模化猪场结核病的诊断

利用提纯结核菌素(牛型)皮内变态反应试验对规模化猪场的猪群进行猪结核的流行病诊断调查,在调查抽检的67个规划化猪场中有3个猪场PPD阳性,通过诊断确定为生猪感染牛分枝杆菌。根据猪结核流行病学以及实验结果对生猪PPD为阳性的养殖场制订猪结核根除措施。     

种猪场圆环病毒2型的血清学调查分析

为了解重庆市忠县种猪场PCV-2的感染情况,笔者采用ELISA法对采自6个种猪场的494头份猪血清进行了血清学调查。结果表明,我县种猪场PCV-2感染率为100%(6/6),PCV-2阳性幅度为7.4%～28.1%,总阳性率为17.4%(86/494),经产母猪阳性率为30.4%(51/168),后备母猪阳性率为17.1%(26/152),断奶仔猪阳性率为5.2%(9/174)。     

规模化猪场疾病的免疫预防

阐述了危害规模化养猪场的8种传染性疾病:猪瘟、猪支原体肺炎、流行性乙型脑炎、猪细小病毒感染、猪伪狂犬病、猪繁殖与呼吸综合征、口蹄疫、传染性萎缩性鼻炎,分别从病原、流行规律、诊断方法、预防疫苗、免疫时间等方面做了论述,以期在规模化养猪中降低其的发生率。     

猪圆环病毒2型疫苗的研究进展

猪圆环病毒2型(PCV-2)是引起断奶仔猪多系统衰竭综合征(PMWS)的主要病原,给全球养猪业造成了巨大经济损失。PCV-2感染可破坏动物机体的免疫系统,造成严重的免疫抑制,容易诱发多种细菌及病毒的混合感染与继发感染,给疾病的诊断和治疗带来巨大的困难。疫苗免疫接种是防控PCV-2感染的有效手段,近年来,全球市场上已先后推出PCV-2灭活疫苗、亚单位疫苗和嵌合疫苗,实验室也致力于研究新型活载体疫苗、核酸疫苗、标记疫苗和小RNA分子疫苗等,文章就PCV-2疫苗的研究进展进行综述,为有效防控猪圆环病毒病提供参考。     

甲鱼嗜水气单胞菌病灭活菌苗的研究

利用嗜水气单胞菌研制了甲鱼嗜水气单胞菌病灭活菌苗,每只甲鱼肌肉注射1.0毫升,14天后产生免疫力,40MLD攻毒100%(15/15)得到保护,免疫期达9个月,4℃保存至少3个月效力不减。现场应用保护率达98%(98/100),无任何副作用及不良反应。     

猪圆环病毒与附红细胞体混合感染的诊治

猪圆环病毒病是一种危害猪群的免疫抑制性疾病。近来我国各地猪场广泛发生该病,同时病猪容易继发和混合感染其他传染病已经成为猪病流行的重要特点,大大增加了确诊和治疗的难度,给我国养猪业造成巨大的经济损失。对重庆地区某规模化养猪场的育肥猪发生的高热、呼吸困难、皮肤上有圆形或不规则黑色斑块状丘疹病例,进行临床诊断、病理剖解、实验室检查,初步确定该场本次爆发的疫病为猪圆环病毒-2型与附红细胞体混合感染。全部猪只注射黄芪多糖,并使用强力霉素、贝尼尔、咪唑苯脲等药物辅助治疗,配合加强营养,猪场消毒,3d后猪只发病数量减少,10d后逐渐恢复。     

检测与诊断猪圆环病毒PCR技术的建立及病毒的分离鉴定

本研究建立了检测与诊断猪圆环病毒的PCR方法,并对该方法进行了标准化研究。该方法快速、敏感、特异性强,可扩增10ng的阳性质粒的DNA,可以从30μL病料组织悬液或全血中扩增检测出PCV,并且该方法可以区分PCV1和PCV-2,对其它病原微生物如PPV、PRRSV、SIV以及许多细菌不能检出。应用此方法对6省市的12个猪场的225份病料进行了检测,对阳性病料进行了病毒分离,对分离的病毒进行了电镜观察与序列测定,结果证实分离的病毒为PCV-2。     

3株O3血清型鳗弧菌灭活疫苗的免疫原性和免疫保护效果

鳗弧菌(Vibrio anguillarum)O3血清型菌株是感染鱼类的重要病原菌,本文研究了3株O3血清型鳗弧菌(SMP1、SMP3和SMP4)灭活疫苗的免疫原性和免疫保护。首先在牙鲆(Paralichthys olivaceus)体内对3株鳗弧菌进行复壮;检测复壮后的菌株毒力,检测的3株鳗弧菌对蓝蔓龙(Trichogaser trichopterus)的半数致死量(LD50)分别为105.1 CFU/ml(SMP1)、104.7 CFU/ml(SMP3)和105.4 CFU/ml(SMP4);制备了3株菌的甲醛灭活疫苗,注射免疫牙鲆,免疫后第7天可检测到牙鲆的血清特异性抗体产生,免疫后第28天的血清特异性抗体效价为1:1280(SMP1)、1:640(SMP3)和1:905(SMP4),提供的免疫保护率(Relative percent survival rate,RPS)为94.4%(SMP1)、100%(SMP3)和73.7%(SMP4)。研究表明,3株致病性O3血清型鳗弧菌菌株具有良好的免疫原性,其中SMP3为最适疫苗候选株。本研究为鳗弧菌O3血清型疫苗的开发应用奠定了基础。     

四川猪2型链球菌病的诊断及综合防治

2005年6/7月四川资阳等地相继发生不明原因的猪源人畜共患病,从41份猪病料中成功分离到19株菌,并通过ATB试条快速鉴定、玻片凝集试验、动物试验、链球菌16SrRNA、CPS2J、MRP三个基因片段的扩增,确诊为猪2型链球菌病。4菌株的药敏试验结果为:对头孢氨苄、羧苄青霉素、氨苄西林、磺胺甲基异恶唑和环丙沙星高度敏感。通过迅速制定和实施猪2型链球菌病综合防控措施,疫情迅速得到了控制,并形成了一套行之有效的防控经验。     

海水鱼类细菌性疾病病原及其检测、疫苗研究概况

概述了海水鱼类常见细菌性疾病包括弧菌病、冬季溃疡病、巴斯德氏菌病、疖病、海水屈挠杆菌病、假单胞菌病、链球菌病、细菌性肾病的病原研究及其检测、疫苗研究概况,为及时了解当前细菌性疾病的研究进展及发展趋势以采取更有效的措施防治疾病提供参考依据。     

Efficacy of a Live‐attenuated Edwardsiella ictaluri Oral Vaccine in Channel and Hybrid Catfish

This study evaluated the efficacy of an oral live‐attenuated Edwardsiella ictaluri vaccine against enteric septicemia of catfish (ESC) in channel and hybrid catfish. The vaccine was delivered one time orally by feeding fish a diet coated with an attenuated E. ictaluri isolate at four doses to deliver between 4 × 10⁶ to 3.2 × 10⁷ viable vaccine cells/g wet feed. Thirty‐five days postvaccination, control and vaccinated fish were challenged with virulent E. ictaluri and mortality was examined for 30 d postchallenge. Mortality of nonvaccinated hybrids (85%) and nonvaccinated channel catfish (73%) was similar but significantly greater than all groups of vaccinated fish. In channel catfish, a trend toward increasing mortality with decreasing dose was observed. Mortality of channel catfish vaccinated with the lowest dose (26.6%) was significantly higher than fish vaccinated with the highest dose (14.1%) but similar to fish vaccinated at the intermediate doses (17.5 and 19.4%). In contrast, mortality of four doses of vaccinated hybrid catfish was similar and ranged between 10.4 and 14.0%. The data demonstrate that the attenuated E. ictaluri vaccine at all four doses tested is effective at reducing ESC‐related mortalities in hybrid and channel catfish.     

Cu2+、Zn2+、Co2+、Ni2+、Li+对西藏拟溞的急性与联合毒性效应

分别将Cu~2+,Zn~2+ Co~'+,Ni~2+和Li~+按照等对数间距法设置浓度梯度,测定其对西藏拟溞(Daphniopsis tibetanaSars)的急性毒性,根据各单种金属的48 h EC_50值,按毒性1:1等距离设置浓度梯度测定这些金属离子对西藏拟溞的联合毒性.结果表明,西藏拟溞对这5种金属离子表现出了较高的耐受性,其毒性由强到弱依次为铜、锌、钻、镍、锂,其24 h EC_50分别为12.75 mg/L,18.32 mg/L,83.26 mg/L,196.97 mg/L,386.34 mg/L;48 h EC_50分别为3.27 mg/L,4.96 mg/L,27.49 mg/L,66.09 mg/L和325.42 mg/L.联合毒性实验中,Cu+Zn,Co+Ni,Co+Li,Ni+Li,Co+Ni+Li,Cu+Zn+Li和Cu+Zn+Co+Ni+Li对西藏拟溞的毒性效应为拮抗作用,而Cu+Zn+Li,Cu+Zn+Ni和Cu+Zn+Co+Ni对西藏拟溞表现出先拮抗作用后协同作用的毒性效应.西藏拟搔对金属离子有较高的耐受性,特别是对含有锂的金属离子组合往往表现为拮抗作用的特征,这很可能是西藏拟搔在西藏高锂盐湖中可高密度存活和快速生长的适应性机制.本研究旨在了解西藏拟溞对金属离子的耐受性,探讨其作为金属离子测试生物的可行性,并为大规模培养中培养液条件优化提供理论依据.     

Vibrogen‐2 vaccine trial in lumpfish (Cyclopterus lumpus) against Vibrio anguillarum

Lumpfish (Cyclopterus lumpus), a native fish of the North Atlantic Ocean, is utilized as cleaner fish to biocontrol sea lice infestations in Atlantic salmon aquaculture. However, bacterial infections are affecting cleaner fish performance. Vibrio anguillarum, the aetiological agent of vibriosis, is one of the most frequent bacterial infections in lumpfish, and effective vaccine programmes against this pathogen have been identified as a high priority for lumpfish. Vibrogen‐2 is a commercial polyvalent bath vaccine that contains formalin‐inactivated cultures of V. anguillarum serotypes O1 and O2, and Vibrio ordalii. In this study, we evaluated Vibrogen‐2 efficacy in lumpfish against a local isolated V. anguillarum strain. Two groups of 125 lumpfish were bath‐immunized, bath‐boost‐immunized at four weeks post‐primary immunization, and intraperitoneally (i.p.) boost‐immunized at eight weeks post‐primary immunization. The control groups were i.p. mock‐immunized with PBS. Twenty‐seven weeks post‐primary immunization, the fish were i.p. challenged with 10 or 100 times the V. anguillarum J360 LD₅₀ dose. After the challenge, survival was monitored daily, and samples of tissues were collected at ten days post‐challenge. Commercial vaccine Vibrogen‐2 reduced V. anguillarum tissue colonization and delayed mortality but did not confer immune protection to C. lumpus against the V. anguillarum i.p. challenge.     

Growth and performance of Atlantic salmon, Salmo salar L., following administration of a rhabdovirus DNA vaccine alone or concurrently with an oil-adjuvanted, polyvalent vaccine

This research demonstrates for the first time an absence of growth-related side effects in Atlantic salmon, Salmo salar L., following the injection of a DNA vaccine alone or concurrently with a commercially available, polyvalent, oil-adjuvanted vaccine. Using weight and specific growth rate measurements, individually tagged Atlantic salmon were monitored for 2028 degree days (dd) post-vaccination. During this time, DNA-vaccinated fish did not differ in weight, length, condition factor or specific growth rate compared to unvaccinated control fish. While differences in weight were observed between unvaccinated control and concurrently vaccinated fish, there were no significant differences in weight, length, condition factor or specific growth rate between concurrently vaccinated fish and adjuvant-vaccinated fish, suggesting that only adjuvant vaccination affected growth. To further determine if concurrent injection of a DNA vaccine and a polyvalent, oil-adjuvanted vaccine had a physiological impact on the Atlantic salmon, swimming performance tests were performed at 106 dd post-vaccination with U _crit,1, U _crit,2, the U _crit recovery ratio (RR) and the normalized RR being similar to values obtained from unvaccinated control fish. In summary, this study shows that concurrent injection of a DNA vaccine and a polyvalent, oil-adjuvanted vaccine does not negatively influence the growth or swimming performance of Atlantic salmon compared to adjuvant vaccination alone.