常见肉鸡球虫病的诊治与体会

<正>鸡球虫病是一种肠道寄生性原虫病,主要由艾美耳属的多种球虫引起。此病是通过球虫卵囊传播,鸡吞食孢子化卵囊而感染,这种病分布广,发生普遍,对雏鸡危害最大。2008年3月,笔者在走访养鸡专业户中,针对常见的     

浅谈鸡球虫病的综合防治

<正>鸡球虫病是由艾美尔属的球虫在鸡的肠道中寄生引起的寄生性原虫病,主要特征为消瘦、贫血、出血性肠炎,雏鸡多发,造成大批死亡,是严重危害养禽业的疾病之一。其传播方式主要是由于雏鸡吃入球虫孢子化卵囊而发生感染。球虫虫卵的抵抗力较强,     

鱼类艾美虫病的发生及防治措施

一.病原 为艾美虫属中的种类,属球虫目,艾美虫科。在我国淡水鱼中已知的有20余种。常见的有青鱼艾美虫、住肠艾美虫、鲤艾美虫、中华艾美虫和鳙艾美虫。艾美虫寄生在肠道等内脏器官内。 各种艾美虫,在发育过程中都产生圆形的卵(膜)囊,直径在6-14μm。成熟的卵囊具有4个孢子,成熟的孢子呈卵形,由一层薄而透明的孢子膜包着。     

球虫病——致病生活史

球虫的生活史可引起球虫病。球虫卵囊通过排泄物传播,雄性配子和雌性配子结合形成合子,合子表面包有保护膜式囊壁。在地面有水、氧和适当温度时,合子分裂成2个或4个孢子母细胞,每个母细胞都包在一个囊内形成卵孢囊。每个孢囊内的孢子的母细胞又分裂成4个或2个子孢子。一旦孢子形成的过程完成,则卵囊成熟为感染性卵囊,就能够侵袭寄主。孢子未形成的卵囊则无侵袭能力。当成熟卵囊被一合适的寄主吞食,卵囊壁受消化液的作用,完成脱囊过程,释放出能游动的子孢子,迅速侵入肠上皮细胞,此时这一寄生物体积增大,最后成为一较大的圆形裂殖体。裂殖体分裂成大量小而细长的裂殖子,然后破坏上皮细胞,裂殖子逸出进入消化道,侵入新的上皮细胞再次进行裂殖生殖。如此反复使上皮细胞严重受损,引起疾病发作。     

牛球虫病症状、诊断及治疗

正牛球虫病是由艾美耳科艾美耳属的球虫寄生于牛肠道粘膜上皮细胞内引起的原虫病,多发生于犊牛。常以季节性地方散发或流行的形式发生,死亡率为20%~40%,给养牛业造成很大危害。1病原寄生在牛体内的球虫有10多种,牛球虫中以邱氏艾美耳球虫和牛艾美耳球虫致病力最强和常见。邱氏艾美耳球虫,卵囊为圆形或     

克迪球预防人工感染鸡球虫病效果的观察

采用接种孢子化球虫卵囊的方法,复制鸡球虫病,观察在饲料中添加克迪球预防鸡球虫病的效果,计算各实验组人工感染柔嫩艾美耳球虫鸡的存活率、相对增重率、血便记分、盲肠病变记分和卵囊值,并求出克迪球的抗球虫指数。结果发现克迪球能完全预防鸡在人工感染球虫卵囊后发生球虫病,用药组未出现盲肠病变和血便,盲肠内容物内检不出卵囊,并能显著提高鸡的相对增重率。表明克迪球对鸡柔嫩艾美耳球虫病有良好的预防作用。     

青海省互助县猪球虫感染情况调查

了解青海省互助县猪球虫病流行情况,为今后综合防治提供依据。采集猪场33头猪所排新鲜粪便,饱和盐水漂浮法检查粪便中卵囊,观察各卵囊形态和大小,依据相关文献确定虫种类别。发现蒂氏艾美尔球虫、猪艾美尔球虫、粗糙艾美尔球虫、平滑艾美尔球虫、极细艾美尔球虫等五种猪球虫,感染率为81.8%,感染强度为1900(400-6600)。     

禽球虫病的防制策略

<正> 球虫病是畜牧生产中常见的一种原虫病,广泛存在于畜禽中,如马、牛、羊、猪、鸡、鸭等都发生此病,尤其以幼龄动物危害最大,常引起大批死亡。鉴于球虫病在世界范围内普遍存在和对畜牧生产的严重危害,探索新的切实可行的防制策略十分必要。 1 饲养管理与球虫感染 育雏阶段,适宜家禽生长的22℃～30℃,正是球虫卵囊发育成孢子囊和子孢子的最佳温度,同时,     

虾肝肠胞虫(EHP)孢子的纯化和计数

采用差速离心和密度梯度离心,从感染虾肝肠胞虫(Enterocytozoon hepatopenaei,EHP)对虾的肝胰腺中,尝试纯化出孢子,并应用透射电镜、荧光桃红染色和血球计数板计数的方法对纯化出的孢子进行了观察和计数。结果表明,从1g的EHP载量为(4.7±2.2)×104 copies/ng DNA的肝胰腺组织中经差速离心和密度梯度离心方法分离到EHP的孢子,电镜观察孢子为大小在0.7～1.2μm的椭圆形,纯化孢子悬液用血球计数板计数显示孢子浓度为5.30×103个/μL,蔗糖密度梯度中的纯化孢子区带含有的孢子总数约1.06×106个。     

南美白对虾的健康养殖技术-5主要疾病的诊断与防治(接上期)

(接上期)3 真菌病(Mycosis)3 1　幼体的真菌病病原　主要为卵菌纲链壶菌目链壶菌科的链壶菌属(Lagenidiumsp )(常见为L callinectes)和离壶菌科离壶菌属(Sirolpidiumsp)。前者的菌丝长而分枝,不分隔,有许多弯曲。菌丝吸收虾体营养,很快长满虾体,待吸收殆尽时,宿主体表的菌丝形成游动的孢子囊原基,生出排放管寄生宿主体外。排放管顶端形成顶囊,内形成游动孢子,排放到水中,游动孢子具有两毛鞭毛,在水中游动片刻后,即附着在对虾卵或幼体上,失去鞭毛,生出被膜,成为休眠孢子。休眠孢子经过短时间休眠后,再萌发成新的菌丝。离壶菌的排放管顶端开…     

间接免疫荧光法检测栉孔扇贝急性病毒性坏死症病毒

用纯化栉孔扇贝(Chlamys farrei)急性病毒性坏死症病毒(AVNV)免疫兔子,以兔抗血清为一抗,荧光标记的羊抗兔抗体为二抗,采用冰冻切片技术,建立了栉孔扇贝AVNV的间接免疫荧光检测方法。用该方法分析栉孔扇贝和海湾扇贝(Argopecten irradians)体内AVNV感染强度,并对感染率进行统计。结果表明,栉孔扇贝的肾脏、肝胰腺中,AVNV阳性信号最强,呈现中度到重度感染,其AVNV感染率100％。鳃丝、性腺及闭壳肌中未检测到阳性信号。在海湾扇贝的肝胰腺及肾中AVNV的感染率也较高。提示AVNV感染扇贝的靶器官主要是肾脏、肝胰腺。对与栉孔扇贝同一海区养殖的海湾扇贝在栉孔扇贝发病期间存活率较高的原因进行了讨论。     

养殖刺参“腐皮综合征”致病菌——灿烂弧菌的原位杂交检测方法的建立与应用

以养殖刺参“腐皮综合征”的重要致病菌——灿烂弧菌Vibrio splendidus的16S~23S间隔区序列,设计特异性引物,用PCR方法制备地高辛(DIG)标记探针,建立了原位杂交技术检测感染刺参体内灿烂弧菌的技术方法,并利用该方法对人工感染刺参和健康刺参各组织进行检测。结果显示,感染刺参的体壁结缔组织、肌肉组织、肠粘膜上皮、辐水管等组织的原位杂交检测呈阳性,而与健康刺参组织无交叉反应。在感染组织中,阳性信号（显色）强弱清晰,能准确反映出灿烂弧菌的侵染部位及感染程度,这为探明灿烂弧菌的感染途径、感染病程等致病机理研究奠定了基础,也为养殖刺参疾病预防和健康管理提供了技术支撑。     

Disseminated infection due to Exophiala pisciphila in Cardinal tetra,Paracheirodon axelrodi

Cardinal tetra, Paracheirodon axelrodi (Schultz, 1956), kept in an ornamental tank, was found to be affected by severe invasive mycosis. Externally, the disease manifested as abdominal swelling, and internally, the anterior part of the intestine was extremely bloated with abundant dematiaceous septate hyphae and an accumulation of fluid. Histopathologically, a granulomatous inflammatory response was observed in the intestine wall, kidney and spleen. We assume that the mycotic agent was primarily deposited in the intestine and was then gradually disseminated to the other organs. DNA sequencing of ITS and LSU rDNA regions and phenotypic characterization were used for identification of the isolated fungus. The obtained data confirmed that the infection was caused by Exophiala pisciphila. The disease was subsequently reproduced in the carp fingerling using intramuscular and intraperitoneal injection of a spore suspension. The 13th day after intramuscular infection, a marked elevation of neutrophils was recorded in the peripheral blood; this involved a proliferation of band forms and segmented forms. As far as we know, this is the first report of infection due to E. pisciphila in Cardinal tetra.     

Herpesvirus salmonis: pathological changes in parenterally-infected rainbow trout, Salmo gairdneri Richardson, fry

Abstract. After fry of rainbow trout, Salmo gairdneri Richardson, had been infected parenterally with Herpesvirus salmonis , moribund or freshly dead specimens were examined histopathologically. The virus produced a generalized infection, the first signs of which appeared after 2–3 weeks. Visceral and respiratory organs and the heart showed major pathological changes, and pancreatic syncytia were judged to be pathognomonic. Kidneys were prime targets for the virus and showed the highest levels of infectivity; lesser amounts of virus were present in the stomach, liver, and intestine. The virus did not spread by contact to produce clinical disease nor could disease or viral replication be induced by parenteral inoculation of yearling Oncorhynchus nerka (Walbaum).     

不同健康程度和抗生素氟苯尼考干预下斑石鲷肠道菌群的结构差异

为了研究不同健康程度和抗生素氟苯尼考干预下斑石鲷肠道菌群结构的差异及其与养殖环境中菌群结构的相关性,采用Illumina Hi Seq PE250高通量测序的方法对健康、亚健康、典型黑身病和口服氟苯尼考条件下的斑石鲷肠道、养殖水体和颗粒饵料中的细菌多样性及群落结构进行了分析比较。结果显示,养殖水体中细菌多样性高于肠道和颗粒饵料。不同健康程度及氟苯尼考干预下斑石鲷肠道中细菌均以变形菌门、厚壁菌门和软壁菌门为主,且对应的操作分类单元(OTU)占样品全部OTU的比例均达到85%以上。黑身病的发生可影响斑石鲷肠道中丰度最高的前20种优势细菌种类的排名次序,其中变形菌门中的弧菌属的相对丰度显著增加,且随着弧菌属丰度的增加,斑石鲷的黑身病症状也逐渐加重。饵料中添加氟苯尼考投喂斑石鲷能使患病鱼肠道弧菌属的丰度从60.33%下降到1.29%,较大程度改变了肠道的菌群结构,并证实氟苯尼考有效防治黑身病。其次,养殖水体和颗粒饵料对斑石鲷肠道菌群也有一定影响,且养殖水体的影响高于颗粒饵料。本研究首次报道了斑石鲷肠道菌群结构,其研究结果为今后斑石鲷的健康养殖、疾病防控及其微生态学研究提供了参考依据和技术支撑。     

条斑紫菜(Pyropia yezoensis)绿斑病病原菌的分离鉴定

绿斑病(Green spot disease)是一种常见的海区栽培条斑紫菜(Pyropia yezoensis)病害，在整个紫菜栽培期间都可能发生，以每年11~12月份最为严重，主要出现在幼叶期和成叶期。首先，在叶状体上出现红色或淡红色小斑，而后逐渐转变为绿色，病斑继续扩展，在叶状体表面形成若干孔洞，后期几乎整个藻体变绿。本研究对日照地区患绿斑病的条斑紫菜进行病原菌分离纯化，得到5株优势菌(编号为Y1~Y5)，人工回感实验结果显示，Y1可以引起健康条斑紫菜发生绿斑病。对Y1进行了生理生化检测、16S rRNA、dnaA和dnaN基因序列分析，确定病原菌为海洋假交替单胞菌(Pseudoalteromonas marina)。对绿斑病的发病进程进行了观察，并检测了培养温度、海水比重和养殖密度等环境因子对绿斑病发生的影响，结果显示，高温和高密度养殖会加速绿斑病病情的发展，海水比重为1.022时，绿斑病发病较严重。本研究确定了一株引起条斑紫菜绿斑病的病原菌，并分析了部分理化因子对感染的影响，为条斑紫菜绿斑病的防控提供了基础数据。     

The effect of Eimeria sp. infection on the condition of blue whiting, Micromesistius poutassou (Risso)

Abstract. Eimeria sp. infection of blue whiting, Micromesistius poutassou (Risso), taken to the north and west of Scotland, was investigated with particular reference to the effect on host condition. Eimeria sp. is a parasite of the liver parenchyma and causes extensive lesions. Juvenile blue whiting were not found to be infected before the late 1-group stage, but all 308 adult (3- to 17-group) fish examined were infected. Condition factor ( k = 100 w/l³ ) showed a statistically significant decrease with increasing intensity of infection. Average value of liver weight, expressed as a percentage of total body weight, also decreased with increasing intensity of infection. It is concluded that Eimeria sp. infection is a major factor contributing to loss of condition in blue whiting from the study area. The loss of weight in fish with moderate-to-heavy infections was estimated at from 6 to 10%; this figure does not take account of mortalities resulting from Eimeria infection nor does it take account of the most heavily infected fish which could not be included in the analysis because sufficiently accurate estimates of the large numbers of oocysts present were not made.     

Structure and function of the small intestine of the tilapia Oreochromis niloticus×Oreochromis aureus (Teleostei, Cichlidae)

This study examined the microscopic structure of the small intestine and digestion and absorption in the hybrid tilapia, Oreochromis niloticus×Oreochromis aureus. The small intestine was lined on the luminal face with villi, which were narrower and more dense in the proximal small intestine and became wider and sparser distally. The columnar epithelial cells lining the villi were predominantly enterocytes containing a brush border, interspersed with mucus containing goblet cells approximately every 4–6 cells. These mucus‐secreting cells contained both acid and basic mucins and increased in density in the distal and the terminal sections of the intestine. Proliferation of enterocytes was observed in the intervillus areas and lower third of the villus. Fish were fed diets of either fish meal or fish meal–wheat to which chromic oxide had been added as a non‐absorbed reference standard. Activity of the pancreatic enzymes, lipase, trypsin and amylase were determined along the small intestine relative to the non‐absorbed marker. Activity of these pancreatic enzymes was maximal in the proximal segments and decreased distally. Changes in the activity patterns of trypsin and amylase were observed with the different diets in the proximal small intestine. Net secretion of both N and fatty acids was found in the hepatic loop and absorption commenced distally decreasing in rate with distance from the pylorus. The pattern of N absorption in the proximal small intestine changed with the different diets. The structure and function of the small intestine of the tilapian omnivore thus are generally similar to mammals and digestion and absorption adapt with diet.     

斑点叉尾鮰TICAM在细菌和病毒感染后的基因表达特征

采用实时定量RT-PCR方法研究斑点叉尾在不同病原(链球菌、嗜水气单胞菌、迟钝爱德华菌、斑点叉尾病毒)感染后TICAM基因在mRNA水平的组织和时空表达特征。感染嗜水气单胞菌可引起TICAM基因在肝脏和脾脏中的上调表达,在注射后24h和12h后上调最大分别为2.3倍和1.9倍;而在头肾和后肠中的表达则下调到感染后48h的0.15倍和24h的0.53倍;感染链球菌后则导致在肝脏、脾脏、后肠和头肾中TICAM基因表达的强烈上调,最大上调幅度为感染后7d肝脏中表达提高了23倍,其次,在脾脏和头肾中基因表达最大可上调到感染前的10倍左右;在感染迟钝爱德华菌后,TICAM基因在肝脏、脾脏、后肠和头肾中表达上调。其中,感染后7d脾脏中的表达提高到感染前的23.1倍。而感染叉尾病毒后,TICAM基因在肝脏、头肾和后肠的表达上调但幅度不大,基因表达在4种组织内表达变化量在1.5～3.7倍范围内波动,而在脾脏中TICAM表达下调,在感染24h后达到最低为感染前的0.13倍。以上实验结果显示,斑点叉尾TICAM基因表达变化与病原感染密切相关,暗示TICAM基因在斑点叉尾天然免疫中起重要作用。