马立克氏病病毒人工感染鸡细胞凋亡病变及凋亡机制研究

通过光镜、电镜观察以及免疫组织化学方法对马立克氏病病毒人工感染鸡的多种组织的实质细胞进行了细胞凋亡病变及凋亡机制研究。结果表明，马立克氏病病鸣肝、肾、心、脾、腺胃、卵巢、羽髓等组织、器官的实质细胞均出现明显的细胞凋亡病变。光镜观察．可见肝细胞、肾小管上皮细胞、腺胃腺上皮细胞、心肌纤维、脾脏内的淋巴细胞、卵巢内的颗粒膜细胞、羽髓细胞的细胞核裂解成大小不等的、致密浓染的球形团块。电镜观察，可见这些细胞的细胞核染色质经历凝集、边集、裂解，最后形成许多凋亡小体等不同阶段。免疫组化研究结果显示，上述细胞均有明显的FasL表达，FasL的表达表明细胞凋亡信号增强，细胞凋亡发生。     

一例鸡马立克氏病与沙门氏菌病混合感染的实验室诊断

为确诊思南县某养殖专业合作社饲养的肉鸡发病死亡原因,采集病鸡羽髓、血样及病死鸡肝脏、脾脏进行细菌分离培养、相关病毒琼脂扩散试验和PCR检测。结果:肝脏组织中分离出沙门氏菌;羽髓琼脂扩散试验检测出马立克氏病抗原,血清琼脂扩散试验检测出马立克氏病抗体;肝脏、脾脏PCR检测出马立克氏病病毒核酸。结论:综合诊断为马立克氏病与沙门氏菌病混合感染。     

马立克氏病鸡红细胞天然免疫黏附功能及超微结构研究

试验研究了马立克氏病鸡红细胞天然免疫黏附活性及其超微结构。选用40羽1日龄海兰褐公雏鸡,随机分为2组,健康对照组（C）和马立克强毒攻毒组（GD）,在26、34、35、44日龄从每组中各取4羽鸡采血、取肝脏,分离肝组织细胞,通过红细胞免疫黏附肿瘤细胞试验及其扫描电镜观察,检测鸡红细胞免疫粘附功能。结果表明,红细胞免疫黏附活性因受机体调节存在动态变化,在攻毒后期,红细胞与马立克氏病肿瘤细胞和自身血浆混合后免疫黏附率接近对照组,红细胞与马立克氏病肿瘤细胞免疫黏附率在34、35 d极显著高于对照组。由此得出,在鸡马立克氏病的发病过程中,红细胞免疫黏附在机体免疫中起着非常重要的作用,这为鸡红细胞免疫分子机理的研究奠定基础。     

不同条件对鸡马立克氏病液氮苗的影响之探讨

鸡马立克氏病是鸡的一种常见的淋巴组织增生性肿瘤疾病。该病给养鸡业造成的损失十分巨大，目前，预防鸡马立克氏病的有效办法主要是接种疫苗，我厂于1979年生产鸡马立克氏病火鸡疱疹病毒活疫苗，二十年共销售了90多亿羽份的冻干活疫苗，为有效预防鸡马立克氏病做出了很大的贡献，近几年来由于超强毒的出现，有些一直使用HVT冻干疫苗的用户明显感觉NHVT     

5例鸡马立克氏病的诊断与病理学观察

2013年7月,甘肃省某鸡场50日龄鸡发生疑似马立克氏病(MD),导致大批死亡。为进一步确诊,分别对5例病鸡采集样品进行琼脂扩散试验和病理组织学观察。结果显示,琼脂扩散试验呈马立克氏病病毒(MDV)抗原阳性。病理学观察,病鸡肝、脾、肾、心等实质器官程度不等肿大,色泽变淡,形成有大小不等和数量不一的灰白色结节。部分病鸡坐骨神经呈单侧性不规则肿粗。病理组织学观察,实质器官及坐骨神经组织中,均有大量多形态淋巴样肿瘤细胞聚集和散在。证明该鸡场鸡病为马立克氏病,高异型性的淋巴样肿瘤细胞的广泛浸润为病理变化特点。     

鸡马立克氏病羽髓琼扩抗原的研制及使用

利用马立克氏病(MD)羽髓琼扩阳性鸡的羽髓制出具有较高的特异性的MD琼扩抗原.该抗原耐低温冻结和耐反复冻融,便于基层使用.     

应用羽囊浸液琼脂扩散法诊断鸡马立克氏病的试验报告

鸡马立克氏病琼脂扩散沉淀反应。我们在学习有关资料的基础上,应用羽囊浸液琼脂扩散法诊断了杭州市郊某大队鸡场发生的鸡马立克氏病。现报告如下: 试验材料和方法一、马立克氏病阳性血清;由哈尔滨兽医研究所供应,批号8102。二、受检鸡羽囊浸液制备:从受检鸡的     

鸡马立克氏病流行情况及防制措施

鸡马立克氏病（MD）是鸡的一种高度接触性传染性并且以淋巴细胞增生为特征的病毒病。目前马立克氏病疫苗保护指数在64．44％－82．86％之间，因此，经马立克氏病疫苗免疫的鸡仍会有一小部分发生马立克氏病，但是，1997年初，福州，连江，三明，泉州，南平，厦门等12个县市的近130个养鸡场（户）所饲养的使用劣质马立克氏病疫苗免疫的约58．4万羽蛋鸡发生了较大规模的鸡马立克氏病（MD），使养鸡场户均蒙受了巨大经济损失，本次MD病流行出现了一定数量的鸡以腺胃肿大为特征，其它内脏肿瘤明显的单纯性腺胃肿瘤，特别是鸡龄越小的鸡越易出现此种病变。     

鸡马立克氏病病毒的分离与初步鉴定

从鸡马立克氏病病鸡拔取羽毛根 ,经处理后接种于 4日龄鸡胚绒毛尿囊膜。盲传到第六代出现典型的马立克氏痘斑。用第7代鸡胚绒毛尿囊膜研磨液与MD阳性血清进行琼脂扩散试验 ,结果出现了明显的白色沉淀线。此结果表明已分离到马立克氏病毒。     

鸡马立克氏病皮肤病变的病理观察

用光镜、电镜及特殊染色法对兰州某鸡场具有皮肤眼观变化的５例自然发生的马立克氏病（ＭＤ）鸡皮肤进行了病理学研究。结果表明,５例ＭＤ病鸡皮肤有明显的肿瘤病变,病变主要表现为肿瘤性滤泡的形成,皮肤病变的发生同病毒羽毛囊上皮内的复制有关。     

Feather-pulp lesions in chickens with naturally occurring Marek's disease lymphomas

Feather pulps of 15-to-35-week-old chickens with Marek's disease (MD) lymphomas were examined histopathologically. Of the 64 chickens, 59 (92.2%) had lymphoproliferative (T-type) lesions in the feather pulp. The T-type feather-pulp lesion (FPL) occurred in all regions, but more frequently in the upper column of the pulp. Severe lesions were distributed throughout the feather pulp. Some of the T-type FPLs regressed to inflammatory lesions consisting of necrosis or loss of constituent cells, edema, and infiltration by small lymphocytes, heterophils, and plasma cells. The regressive T-type FPL was usually diffuse throughout the tumorous lesions, but proliferative foci were often seen concomitantly with regressive lesions. The grade and histologic picture of T-type FPLs in chickens correlated well with those of the visceral lymphomas. These findings suggest that the severity of MD lymphoma is predictable without autopsy by examining feather-pulp samples.     

Cellular and cytokine responses in feathers of chickens vaccinated against Marek's disease

In Marek's disease virus infection, feather follicle epithelium (FFE) constitutes the site of formation of infectious virus particles and virus shedding. The objective of this study was to characterize cellular and cytokine responses as indicators of cell-mediated immune response in FFE and associated feather pulp following immunization against Marek's disease. Analysis of feather tips collected between 4 and 28 days post-immunization (d.p.i.) from chickens vaccinated post-hatch with either CVI988/Rispens or herpesvirus of turkeys revealed that replication of these vaccine viruses started at 7d.p.i., peaked by 21d.p.i., and subsequently, showed a declining trend. This pattern of viral replication, which led to viral genome accumulation in feather tips, was associated with infiltration of T cell subsets particularly CD8+ T cells into the feather pulp area and the expression of cytokine genes such as interferon-gamma, which is an indication of elicitation of cell-mediated immune responses at the site of virus shedding.     

鸡马立克病病毒强毒与疫苗毒PCR鉴别检测方法的建立

在Ⅰ型马立克病病毒(MDV)基因组中针对132 bp串联重复序列的两侧合成一对引物,应用PCR技术对临床病例采集的疑似马立克病肿瘤病变鸡肝组织和1日龄接种CVI988弱毒疫苗的健康雏鸡羽髓样本进行检测。结果表明,从临床病例采集的10份肝脏组织,7份扩增出一条314 bp的条带,相当于2个拷贝数的132 bp串联重复序列;在接种疫苗健康雏鸡的羽髓样本中,扩增出与CVI988弱毒一致的PCR图谱,相当于6个~8个或更多拷贝数的132 bp串联重复序列。根据PCR图谱的差异即可鉴别MDV强毒株与CVI988疫苗弱毒株。     

Marek's disease virus-induced skin leukosis in scaleless chickens: tumor development in the absence of feather follicles

Marek's disease virus (MDV) is an oncogenic cell-associated herpesvirus that causes T-cell lymphoma in chickens. Lymphoproliferative neoplasms in Marek's disease (MD) occur in various organs and tissues, including the viscera, peripheral nerves, skin, gonads, and musculatures. MDV is restrictively produced in the feather follicle epithelial (FFE) cells, and it gains access to the external environment via infected cells or as infectious enveloped cell-free virus particles. The goals of the present study were to 1) determine whether the MDV-induced skin lesions are neoplastic in nature or inflammatory reactions to viral infection, 2) determine whether physical presence of feather follicles (FF) is necessary for skin tumor development, and 3) study the role of skin epithelial cells not associated with feathers or FF in the replication and dissemination of infectious virus particles. Scaleless chickens that produce only a few scattered feathers and no sculate scales along the anterior metatarsi were used as a unique model to study the pathogenesis of dermal lesions. Histologic and immunohistochemical analysis revealed that the cutaneous lesions were tumorous as was manifested by massive accumulation of lymphoblasts and extensive activation of meq oncoprotein, the hallmark of MDV oncogenesis, within the skin lesions. Neoplastic cutaneous lesions in the scaleless chickens indicate that feather follicles are not necessary for skin tumor development. Finally, our preliminary data indicate that inoculation with supernatant fluid from homogenized and sonicated skin samples of MDV-infected scaleless chickens induces MD in susceptible birds, suggesting that skin epithelial cells not associated with FF also harbor infectious viral particles.     

A novel DNA virus associated with feather inclusions in psittacine beak and feather disease

The nature of feather inclusions was characterized in 32 psittacine birds (30 cockatoos, one peach-faced lovebird (Agapornis roseicollis), and one red-lored Amazon parrot (Amazona autumnalis autumnalis] with naturally-acquired psittacine beak and feather disease. Intranuclear inclusions within feather epithelial cells and intracytoplasmic inclusions within macrophages in the feather epithelium and pulp cavity contained psittacine beak and feather disease viral antigen when stained by the avidin-biotin complex immunoperoxidase technique. Ultrastructurally, inclusions were observed primarily within macrophages and to a lesser extent within epithelial cell nuclei. Macrophage inclusions appeared as paracrystalline arrays of viral particles. Intranuclear inclusions were less well defined, although scattered viral particles were present. Intracytoplasmic and intranuclear particles in ultrastructural preparations were identified by colloidal gold labeling as psittacine beak and feather disease virus. Feather epithelium was more frequently and severely involved in the disease process than was adjacent follicular epithelium. Plucked feathers with an intact epidermal collar and feather epithelium were preferred to follicular biopsies for histopathologic examination.     

马立克氏病病毒致瘤相关基因meq在不同病变组织中的变化

以MSB-1肿瘤细胞建立的马立克氏病为病理模型,利用PCR技术扩增不同病变组织中的meq基因,构建meq基因重组阳性质粒,测定和比较它们的核苷酸和氨基酸序列。结果显示,与L-meq（1 200 bp）和标准株GA的meq（1 020 bp）比较,MSB-1细胞和脾脏肿瘤组织的meq基因（1 197 bp）、羽髓meq基因（1 017 bp）分别相应缺失3个碱基（CCA）;MSB-1细胞和脾脏肿瘤组织的meq基因具有与L-meq相同的180 bp插入序列;氨基酸序列也发生相应变化。结果表明,meq基因在不同病变组织中的核苷酸序列发生了变化,这种变化可能与马立克氏病病毒的致瘤机制有关。     

Relationship between Marek's disease and the time course of viral genome proliferation in feather tips

A total of 114 male chickens from three sire families of a commercial cross of White Leghorn chickens were infected with RB-1B Marek's disease (MD) virus at 21 days of age by exposing them to chickens previously inoculated with MD virus. The presence of virus in feather tips, feather pulp, and MD viral antibodies indicated all chickens became infected. The first virus-positive chickens were observed at 12 days postexposure (dpe). The frequency reached a maximum at 27 dpe and then decreased. At 80 dpe, when the experiment was terminated, no viral DNA was detected in the feather pulp of the surviving chickens (82%). Death from MD was first observed at 38 dpe and reached 18% by the end of the experiment, with spleen lesions being the major MD lesion. The viral genome titers in spleen extracts of chickens with MD lesions was negatively correlated with the time of death, and, similar to feather pulp, none of the surviving chickens was virus positive at the end of the experiment. Quantization of the viral genome titers in feather tip extracts at 27 and 38 dpe revealed a positive correlation with the presence of MD lesions, but only in the declining phase (38 dpe) and not at the peak (27 dpe) of the viral titer. Sire effects were significant, indicating the presence of genetic factors that affect viral proliferation. Again, significance was only observed at 38 dpe and not at 27 dpe. The results indicate that, in this commercial line, 1) all chickens were susceptible to infection via contact exposure, 2) all surviving chickens recovered from the viral infection, and 3) it is not sufficient to measure viral titers at a single time point when using viral titers as an endpoint for MD susceptibility.     

Replication of turkey herpesvirus and Marek's disease virus in chick embryo skin organ culture.

Turkey herpesvirus (HVT) and an attenuated Marek's disease virus (MDV) replicated in organ cultures of chick embryo skin as assessed by immunofluorescence and/or electron microscopy. HVT-specific immunofluorescent antigen was detected in the feather follicle epithelium (FFE) and in the surface layer of the skin epidermis. Electron microscopy of infected explants revealed herpes-type cytopathology. Immature particles of both viruses appeared first in the nucleus. Oval or horseshoe-shaped non-enveloped particles of HVT and enveloped virions of MDV were seen in the cytoplasm of some transitional cells. The difference in the ability of HVT and MDV to form an envelope was believed to account for the difference in their transmissibility in chickens. The results indicated that HVT replicated in the FFE and in the epidermis of the skin. However, attempts to localise the site(s) of MDV replication by electron microscopy were unsuccessful.     

安徽省鸡常见病毒性肿瘤病的检测与调查

应用已建立的鸡肿瘤病快速鉴别诊断技术对源自安徽省5个不同地区的46个鸡群的肿瘤病、抑制病疑似病、死鸡305羽进行检测。结果表明,马立克氏病的阳性率为39．34%(120/305),禽网状内皮组织增生征阳性率为8．52%(26/305),禽白血病阳性率为2．624%(8/305)；另对17群未进行MD免疫的肉鸡进行随机抽样检测,其中5个鸡群检测出马立克氏病病毒强毒,阳性率为29．41%(5/17),阳性群的平均检出率为24 %。