兔脑炎原虫病及其诊治

<正> 兔脑炎原虫病是由脑炎原虫引起的一种慢性、隐性或亚临床原虫病。由于该病常呈隐性感染,故多不为人们所注意。兔脑炎原虫病广泛分布于世界各地,近年来我国也常见对该病的研究报道。在养兔场,兔脑炎原虫病是一种常见的感染,家兔的感染率一般为15—76％。这样高的感染率亦给养兔业带来了一定的经济损失。兔脑炎原虫属于小孢子虫目、微粒子虫     

兔脑炎原虫引起的脑组织细胞凋亡

为了调查兔脑炎原虫引起脑组织细胞的凋亡情况,本研究用特殊染色、TUNEL染色、凋亡蛋白免疫组化染色和Western blot,对40只家兔的脑组织进行了详细研究。结果表明,病兔的脑组织中均检出了肉芽肿和脑炎原虫。脑炎原虫所引起的脑细胞凋亡主要发生于脑血管的内皮细胞、星形胶质细胞、巨噬细胞和上皮样细胞,其次为病变所累及的神经细胞。用TUNEL的免疫酶-荧光染色和抗凋亡蛋白的免疫组化染色,凋亡细胞均呈强阳性反应,被染成棕褐色。对脑组织蛋白提取物进行Western blot检测,病兔脑组织中P~(53)、Bcl-2、Bax和c-Myc凋亡基因蛋白表达量明显高于对照兔,差异非常显著(P0.01)。结果表明,兔脑炎原虫在脑组织细胞内寄生时可以引起细胞凋亡。     

肾脏病变对隐性兔脑炎原虫病的诊断研究

为了尽快诊断隐性兔脑炎原虫病,本研究对屠宰检验发现的31只有病变的兔肾,用病理学方法进行了兔隐性脑炎原虫感染的研究。结果证明:31只兔肾均以间质性肾炎为基本病变,在3只兔肾组织的肾小管上皮中检出假囊,革兰氏染色鉴别其为兔脑炎原虫假囊。脑炎原虫性间质性肾炎的病变主要包括两种,即弥漫性间质性肾炎和增生性肉芽肿性肾炎。总之,通过对肾脏病变的检查,能及早发现隐性兔脑炎原虫病。     

兔脑炎原虫病的诊防研究

兔脑炎原虫病是由兔脑炎原虫引起的一种人畜共患的专性细胞内寄生虫病。兔脑炎原虫具有广泛的宿主范围,对家畜、家禽、野生动物和实验动物等均有易感性,其中家兔的感染率最高,可高达76％,在很多兔场中广泛流行,不但给养兔业造成严重的经济损失,而且危及兔源性食品的加工及食用安全,给公众健康带来了潜在而且持续的威胁;     

兔脑炎原虫病诊治

兔脑炎原虫病是一种人畜共患的寄生虫病,导致兔脑炎的病原为小孢子门微孢子虫纲科的兔脑炎原虫.病原侵害的主要靶器官为脑组织和肾脏.患病动物主要表现为头颈歪斜,昏睡,震颤,局部或全身轻瘫.该原虫可自然感染多种动物,如兔、小鼠、大白鼠、麝鼠、豚鼠、仓鼠、山羊、绵羊、猪、马、家犬、狐狸、家猫等,其中家兔感染率最高,且多为隐性感染或慢性感染.该病给人类肉食安全造成了一定的威胁.     

兔脑炎原虫病的诊防研究

兔脑炎原虫病是由兔脑炎原虫引起的一种人畜共患的专性细胞内寄生虫病.兔脑炎原虫具有广泛的宿主范围,对家畜、家禽、野生动物和实验动物等均有易感性,其中家兔的感染率最高,可高达76%,在很多兔场中广泛流行,不但给养兔业造成严重的经济损失,而且危及兔源性食品的加工及食用安全,给公众健康带来了潜在而且持续的威胁;另外实验动物的隐性感染给科研结果的判断造成了极大的干扰.我国作为养兔大国,对本病进行深入研究,有着重大的社会意义和经济意义.     

扫描及负染电镜在兔脑炎原虫病诊断中的应用

12只临床表现头颈歪斜、昏睡、震颤、局部或全身轻瘫的可疑为兔脑炎原虫病的獭兔 ,对其肾脏皮髓交界和尿沉渣分别进行了扫描电镜和负染电镜观察 ,看到了大小为 1～ 1 .5× 1 .4～ 2 .5μm,形态呈卵圆形和杆状的兔脑炎原虫。阳性检出率为 1 0 0 %。说明扫描及负染电镜术是诊断兔脑炎原虫病的一种较为可靠的技术。     

兔脑炎原虫病防制研究进展

兔脑炎原虫病是由兔脑炎原虫引起的一种人畜共患的寄生虫病 ,该虫可感染各种动物和人。其中以兔的感染较为严重 ,且多为隐性或慢性感染。因此对兔脑炎原虫病的诊断、预防及治疗显得非常重要。过去对此病的诊断通常采用病理组织学检查法或血清学等方法 ,而且没有有效防治该病的措施。随着近年来国际上对此病研究的深入 ,出现了一些新型的诊断技术如 PCR技术和透射电镜术等 ,并能用一些药物进行防治 ,如阿苯达唑和多胺等。文章重点就诊断和防治两方面进行了概述     

兔脑炎原虫病的研究进展

<正>兔脑炎原虫病又叫微孢子虫病(Microsporidiosis)或脑炎微孢子虫病,是由兔脑炎原虫引起的人畜共患寄生虫病。其病原是一些专性寄生于细胞内的真核原生动物,广泛寄生于包括人在内的大量脊椎动物和无脊椎动物体内。其中兔脑炎原虫发现于1917年,是研究最早的哺乳动物中典型的微孢子寄生虫,也是使兔自然感染的唯一微孢子虫。微孢子虫虽然发现很早,但当时未引起人们的高度重视,直到1981年艾滋病大流行后,微孢子虫才作为病     

小规模兔场常见寄生虫病的诊断及防治

兔寄生虫病是寄生虫寄生于家兔体内外，以多种方式掠夺家兔的营养，使其机体机能降低、健康受到损害、生长缓慢甚至死亡的一类疾病。寄生虫病是与传染病和普通病并列的三大疾病之一，其发生和流行严重影响养兔业的发展。小规模兔场常见的寄生虫病有球虫病、弓形虫病、兔脑炎原虫病、     

IL-2在自然感染兔脑炎原虫獭兔体内免疫作用的研究

为观察 IL-2在自然感染兔脑炎原虫獭兔体内的免疫作用 ,用双抗体夹心 EL ISA试剂盒对 8只自然感染兔脑炎原虫的獭兔和 4只健康长耳白对照兔的血清及培养 3 d和 4d的脾和淋巴结的细胞培养上清中的 IL-2进行了检测。检测结果为病兔与对照兔 IL -2平均含量差异不显著 (P >0 .0 5) ,但病兔 IL -2平均含量高于对照兔。提示 IL -2对病兔产生了一定的免疫作用 ,但可能不扮演主要角色     

雏鸡感染毒害艾美耳球虫后血清免疫球蛋白含量的动态变化

采用间接ELISA法检测雏鸡初次及二次感染毒害艾美耳球虫(Eimerianecatrix)后血清免疫球蛋白含量的动态变化。结果表明,雏鸡初次感染E.necatrix 后10 d~ 14 d血清IgG, IgM, IgA 含量开始增加,16 d~18 d达到峰值;雏鸡二次攻击性感染E.necatrix 后2 d~7 d,其血清的上述3种免疫球蛋白含量均不同程度低于初次感染雏鸡,随后开始回升,至10 d~14 d明显高于相应对照及初次感染雏鸡。血清抗体,特别是IgG介导的体液免疫,在雏鸡抵抗E.necatrix初次及二次感染中发挥了重要作用。     

Prevention and treatment of Encephalitozoon cuniculi infection in rabbits with fenbendazole

The efficacy of fenbendazole for preventing an experimental infection of Encephalitozoon cuniculi and for eliminating the spores from the central nervous system of naturally infected rabbits was investigated. Fenbendazole (20 mg/kg bodyweight daily) was administered from seven days before until two or 21 days after rabbits had been infected orally with 10(6) spores of E. cuniculi. Both regimens were effective in preventing the establishment of the parasites, as demonstrated by negative parasitic-specific serology and by the failure to isolate the parasite from brain tissue. In naturally infected, seropositive rabbits, parasites were successfully isolated from seven of nine untreated animals, but not from the brain tissue of eight animals treated with fenbendazole-medicated pellets for four weeks.     

Passive transfer of naturally acquired specific immunity against West Nile Virus to foals in a semi-feral pony herd

Horses naturally exposed to West Nile Virus (WNV) or vaccinated against WNV develop humoral immunity thought to be protective against development of clinical disease in exposed or infected animals. No reports evaluate the efficacy of passive transfer of naturally acquired specific WNV humoral immunity from dam to foal. The purpose of this study was to investigate passive transfer of naturally acquired immunity to WNV to foals born in a herd of semi-feral ponies, not vaccinated against WNV, in an endemic area, with many dams having seroconverted because of natural exposure. Microwell serum neutralization titers against WNV were determined in all mares and foals. Serum IgG concentration was determined in foals by serial radial immunodiffusion. Differences in IgG concentration between seropositive and seronegative foals were examined by means of the Mann-Whitney U-test. Linear regression was used to evaluate the association between mare and foal titers. Seventeen mare-foal pairs were studied; 1 foal had inadequate IgG concentration. IgG concentration was not different between seronegative and seropositive foals (P = .24). Mare and foal titers were significantly correlated in foals with adequate passive transfer of immunity (Spearman's rho = .84; P < .001); >90% of the foal's titer was explained by the mare's titer (R2 = 0.91; P < .001). Passive transfer of specific immunity to WNV is present in pony foals with adequate passive transfer of immunity born to seroconverted mares.     

鸡贫血因子病全身免疫功能变化的研究

用鸡贫血病毒（ＣＡＶ）感染１日龄ＡＡ雏鸡,以未感染同龄ＡＡ雏鸡为对照,感染后不同时间检测其外周血液Ｔ、Ｂ细胞数量和ＩｇＧ,ＩｇＭ,ＩｇＡ含量,胸腺,法氏囊,脾脏ＩｇＧ,ＩｇＭ,ＩｇＡ抗体生成细胞和Ｔ细胞数量以及Ｔ、Ｂ细胞增殖功能;胸腺和脾脏白细胞介素２（ＩＬ－２）和干扰素（ＩＦＮ）诱生活性等的动态变化。     

桔皮油对家兔耳(足)螨病治疗试验

用桔皮油对505只耳(足)螨病兔进行治疗,其中耳螨兔432只,耳、足螨混合感染兔73只,用药后7d病免全部冶愈,60～180d复查,未发现复发病例。离体杀螨试验,桔皮油经过5～10min将螨虫全部杀死。由此证明,桔皮油具有药效快、杀虫率高、对兔体无毒副作用等特点。     

脑炎原虫病兔免疫器官的病理形态学观察

研究脑炎原虫病兔外周免疫器官的形态学变化,采集20只病兔和12只对照兔的淋巴结、脾脏和圆小囊,通过临床检查,病理剖检,病理切片的HE染色、吉姆萨染色和免疫组织化学染色进行了比较观察。结果表明病兔淋巴结内的淋巴小结数量增多,生发中心明显,髓索增粗,副皮质区增宽。脾脏的脾小结增多,变大,具有明显的生发中心,边缘区明显增宽,动脉周围淋巴鞘明显变大,聚集大量淋巴细胞。圆小囊的淋巴小结增大,数量增多,生发中心明显,淋巴小结周围弥散大量淋巴细胞。通过α-ANAE和sABC染色,在淋巴结、脾脏和圆小囊中均可检出大量T细胞、巨噬细胞和IgG阳性细胞。据此认为患脑炎原虫病时,病兔的体液免疫和细胞免疫均增强,但以细胞免疫反应更强。     

Immunohistochemical identification of Encephalitozoon cuniculi in phacoclastic uveitis in four rabbits

PURPOSE: Encephalitozoon cuniculi is a microsporidium with a wide range of mammalian hosts. In rabbits it can be responsible for cataract and lens-induced uveitis (LIU). The aim of this study was to provide specific immunohistochemical demonstration and localization of E. cuniculi within the eye, in rabbits with LIU. MATERIAL AND METHODS: Four rabbits were presented with a white mass in the eye and iris discoloration. Complete ophthalmic examinations were performed and a presumptive diagnosis of LIU was made in all cases. Initial therapy with a topical steroid, atropine and systemic enrofloxacin was instituted while serologic (IFA or ICA tests) and cytologic lab results were pending. The final outcome in all cases was enucleation. Routine histology and immunohistochemistry (ABC method) with an antiserum anti-Encephalitozoon cuniculi were performed. RESULTS: Indirect immunofluorescence performed on one rabbit serum expressed a titer of 1 : 32; carbon immunoassay on the serum of the other three rabbits expressed a titer of 1 : 5120 in one, and a titer of 1 : 2560 in the other two cases. Histologically, an intraocular, locally extensive pyogranulomatous infiltration that partially filled the posterior chamber, encasing a wide anterior lens capsule break, was detected in all cases. Immunohistochemically, spores reacting with anti-Encephalitozoon cuniculi antiserum were present in all specimens, occasionally within macrophages and lens epithelial cells. CONCLUSION: Detection of E. cuniculi in rabbits with phacoclastic uveitis has been investigated in the past with different methods. Based on our results, we suggest that immunohistochemistry should be regarded as a useful tool both for specific demonstration of E. cuniculi and for its localization within tissues.     

Serological survey for antibodies to Encephalitozoon cuniculi in rabbits in Taiwan

Encephalitozoon cuniculi (E. cuniculi) is a microsporidian parasite commonly found in rabbits that can infect humans, causing encephalitozoonosis. Our laboratory recently confirmed the first case of encephalitozoonosis in a rabbit in Taiwan; the prevalence of encephalitozoonosis is not well documented, even when many clinics suspect pet rabbits as being infected. This study surveys the seropositivity of E. cuniculi using carbon immunoassay (CIA) and enzyme-linked immunosorbent assay (ELISA). Serological examination of 171 rabbits using CIA and ELISA showed that 63.2% (108/171) and 67.8% (116/171) were seropositive against E. cuniculi, respectively. Thirteen of the 14 rabbits (92.9%) with neurological symptoms were seropositive. Except for gender, health status and location had a significant effect on E. cuniculi seropositivity (p<0.05). Adult rabbits aged older than 4 months exhibited significantly higher seropositivity for E. cuniculi than young rabbits (p<0.05). In conclusion, this study shows that E. cuniculi is present and widespread among healthy rabbits in Taiwan. Therefore, the fields of veterinary and human medicine in Taiwan should be aware of this zoonotic issue and the resulting public health concern of encephalitozoonosis.     

Humoral antibody response of rabbits to experimental infection with Encephalitozoon cuniculi

Six female rabbits (Oryctolagus cuniculus) were experimentally infected intravenously with approximately 1.5 X 10(7) live spores of Encephalitozoon cuniculi. Head tilt was observed as the single clinical sign in only one of the six animals. Antibody response was registered over 68 days postinfection using the indirect immunofluorescence test (IFT) for IgM and IgG, and the carbon immunoassay (CIA). IgG titers reached a level of 160-2560 after a latent phase of 13-28 days, followed by a 2-4 week relatively steep increase. The IgM seroconversion was faster than that of IgG and occurred at the beginning of the antibody response. Thus, simultaneous detection of both IgM and IgG allowed the infection to be identified as recent. Long, short, and episodic antibody responses could be distinguished: the IgG titer continued to increase on Day 68 in one animal (long response) and began to decrease between Days 45 and 63 in three other animals (short response). In two additional animals the seroconversion was very short, occurring between Days 13 and 41, and 28 and 52, respectively (episodic response). The CIA proved to be specific, reliable, and simple to perform; titers were slightly higher than in the IFT. Parasite pseudocysts were detected scattered throughout the brain on Day 68 in four of the six rabbits. The persistence of antigen in the brain did not correlate with antibody response, which in most cases was shorter.