法氏囊组织在鸡淋巴细胞性白血病发生发展中的变化

用鸡淋巴细胞性白血病病毒ＲＡＶ－１株接种３５只１日龄伊莎鸡雏，于接毒后不同批次扑杀，采取法氏囊做组织学、免疫细胞化学、透射电镜观察。结果：接毒后１个月，法氏囊滤泡髓质淋巴细胞开始转化，接毒后２～５个月更明显，在法氏囊滤泡髓质区形成淋巴细胞克隆增殖灶。接毒后６个月，法氏囊萎缩。ＢＡ法染色表明法氏囊一直存有病毒和群特异性抗原，以接毒后３～４个月含量最高。电镜观察，在接毒后１～４个月的实验鸡法氏囊滤泡髓质淋巴细胞、巨噬细胞和网状细胞中观察到ＬＬ病毒粒子。组织学、免疫细胞化学和电镜观察都表明法氏囊是该病毒的主要靶器官，法氏囊决定鸡淋巴细胞性白血病的发生发展。     

鸡淋巴细胞性自血病病毒和群特异性抗原（P27）在体内的分布与消长

应用生物素－亲和素法和电镜技术对接种鸡淋巴细胞性白血病病毒的实验鸡作了研究。结果：接种后１５ｄ的两只发病鸡雏骨髓中含有大量病毒抗原和群特异性抗原，ＢＡ阳性细胞主要是成髓细胞。接种后１个月一只实验鸡骨髓中形成成髓细胞性肿瘤结节，结节中成髓细胞ＢＡ弱阳性。接种两个月以后骨髓结构正常，各细胞群ＢＡ弱阳性。接种后１５ｄ法氏囊中即有病毒抗原和群特异性抗原，但主要是成髓细胞阳性。接种后２－５个月，法氏囊淋巴滤泡中一直存有病毒抗原和群特异性抗原，但以接毒后３－４个月时含量最高。接毒后６个月，法氏囊萎缩，结缔组织和成淋巴细胞ＢＡ弱阳性。电镜观察，在接毒后１－４个月的实验鸡法氏囊滤泡髓质巨噬细胞胞浆内和胞膜表面、网状细胞胞浆内和淋巴细胞之间观察到大量ＬＬ病毒粒子。根据ＢＡ法染色在法氏囊检出ＢＡ阳性细胞，或电镜在法氏囊检出大量ＬＬ病毒粒子。均可与ＭＤ相区别而建立ＬＬ病理学诊断。     

鸡实验性淋巴细胞性白血病的病理学研究

给３５只１日龄伊莎褐蛋母鸡雏腹腔接种淋巴细胞性白血病病毒ＲＡＶ－１株，应用常规病理技术，对接毒后第１５天、１、２、３、４、５、６个月７个批次的实验鸡做了病理学研究。结果：接毒后１５ｄ和１个月，部分实验鸡发生了成髓细胞性白血病，主要表现为骨髓成髓细胞大量增生，或形成成髓细胞性肿瘤结节，肝、心、肾、法氏囊等内脏器官出现成髓细胞聚集；接毒后２～６个月，实验鸡发生了淋巴细胞性白血病，主要表现为法氏囊髓质淋巴细胞发生转化，成淋巴细胞克隆增殖形成成淋巴细胞克隆增殖灶，在肝、心、肾、脾、腺胃等器官中形成成淋巴细胞性肿瘤结节。据此，可对鸡淋巴细胞性白血病做出病理组织学诊断。     

鸡实验性淋巴细胞性白血的病理学研究

给３５只１日伊莎褐蛋母鸡雏腹腔接种淋巴细胞性白血病病毒ＲＡＶ－１株、应用常规病理技术，对接毒后第１５天、１、２、３、４、５、６个７批次的实验鸡做了病理学研究。结果：接毒后１５ｄ和１个月，部分实验鸡发生性细胞性白血病，主要表现为骨髓在髓细胞大量增生，或形成成髓细胞性肿瘤瘤结节，肝、心、肾、法氏囊等内脏器官出现成髓细胞聚集，接毒后２－６个月，实验鸡发生了淋巴细胞性白血病，主要表现为法氏囊髓淋巴细胞发生     

鸡实验性成髓细胞性白血病的细胞化学及超微结构

用鸡成髓细胞性白血病病毒（ＡＭＶ）ＢＡＪ－Ａ株鸡传代血浆毒感染１日龄伊莎鸡雏２０只，在接毒后１９￣２５ｄ于濒死期扑杀、采样，进行细胞化学和电镜检查。结果表明，肝、肾、法氏囊、胸腺及血液的成髓细胞来源于骨髓；其成髓细胞胞浆、胞膜及细胞间隙存在带有囊膜的含核心的病毒粒子。     

鸡淋巴细胞性白血病病毒和群特异性抗原（P^27）在体内的分布与消长

应用生物素－亲和素法和电镜技术对接种鸡淋巴细胞性白血病病毒的实验鸡作了研究。结果：接种后１５ｄ的两只发病鸡雏骨髓中含有大量病毒抗原和群特异性抗原，ＢＡ阳性细胞主要是成髓细胞。接种后１个月一只实验鸡骨髓中形成成髓细胞性肿瘤结节，结节中成髓细胞ＢＡ弱性。接种两个月以后骨髓结构正常，各细胞群ＢＡ弱阳性。接种后１５ｄ法氏囊中即有病毒抗原和群特异性抗原，但主要是成髓细胞阳性，接种后２￣５个月，法氏囊淋巴滤泡     

传染性法氏囊病病毒对法氏囊生长发育的影响

本试验运用传染性法氏囊病病毒变异 Ｅ 株，通过泄殖腔和鼻腔接种 １，８，１５，３０ 日龄雏鸡，通过尿囊腔接种８， １３，１８ 日龄鸡胚，全面而系统地观察了接毒后不同时间法氏囊的组织形态学变化，探讨了传染性法氏囊病病毒对胚胎发育时期和雏鸡发育时期法氏囊生长发育的影响。结果表明， Ｉ Ｂ Ｄ Ｖ 感染后１２～４８ ｈ，雏鸡法氏囊粘膜上皮细胞肿胀，坏死脱落，淋巴滤泡髓质部及皮质部淋巴细胞不同程度变性、坏死、排空，形成腺管样结构或囊状空泡： 接毒后７２～１４４ ｈ，法氏囊淋巴滤泡淋巴细胞坏死排空，淋巴滤泡萎缩，网状结缔组织大量增生，而胚胎发育时期，法氏囊粘膜上皮肿胀变性，法氏囊淋巴滤泡形成延迟或不完整，淋巴滤泡内淋巴细胞缺乏或空虚，说明传染性法氏囊病病毒变异 Ｅ 株对法氏囊造成严重的组织学危害，从而导致法氏囊生长发育阻滞，组织学形态和结构严重受损。     

实验性新城疫雏鸡免疫器官的病理学研究

给２８日龄伊莎雏鸡人工接种新城疫病毒后，应用常规病理学检验、细胞化学和免疫组化技术对免疫器官的病理学变化作了研究。接毒１２ｈ，法氏囊滤泡的髓质、胸腺小叶的髓质、脾白髓、盲肠扁桃体的淋巴小结及弥散淋巴组织的部分淋巴细胞和网状细胞首先出现核浓缩、胞浆固缩等坏死变化。接毒１～３ｄ（潜伏期），骨髓、法氏囊滤泡、胸腺小叶、脾白髓和红髓、盲肠扁桃体粘膜层及弥散淋巴组织的淋巴细胞、巨噬细胞和网状细胞发生核浓缩、碎裂、胞浆固缩，强嗜酸性等坏死变化。接毒４～６ｄ死亡病例，这些免疫器官的淋巴组织散在呈蜂窝状空泡结构坏死灶（法氏囊为滤泡坏死），进一步崩解成无结构嗜酸性颗粒状物质。这些坏死变化可作为雏鸡新城疫诊断的根据。     

传染性法氏囊病病毒（IBDV）人工感染SPF鸡的病理学观察

取３２０只３０～４０Ｈ龄ＳＰＦ鸡，经滴鼻和点眼接种传染性法氏囊病病毒（ＩＢＤＶ），接种后２４～７２ｈ出现死亡，病死率５１．２５％，死亡鸡剖检变化主要为法氏囊肿胀、出血，甚至呈紫葡萄样，脾脏肿大、出血，骨骼肌出血，腺胃肌胃交界处出血。病理组织学变化，呈现以法氏囊淋巴滤泡内髓质淋巴细胞坏死为主的特征性病变，并可在巨噬细胞浆内发现病毒包涵体。电镜观察，在法氏囊内淋巴细胞、异染性细胞、巨噬细胞浆内，见大量晶格状排列的病毒粒子和包涵体，表明ＩＢＤＶ首先损害法氏囊淋巴滤泡髓质内未成熟的Ｂ淋巴细胞，病毒在淋巴细胞内以包涵体方式增殖。     

应用生物素-亲和素法检测实验性传染性法氏囊病病鸡体内的病毒分布与消长

应用生物素—亲和素(BA)法检测实验性传染性法氏囊病(IBD)鸡,在法氏囊、脾脏、盲肠扁桃体、胸腺、肝脏、肺脏、肾脏和心脏均检出了阳性细胞,并证明鸡传染性法氏囊病病毒(IBDV)最早定位于法氏囊滤泡髓质区的淋巴细胞胞浆内并进行复制,法氏囊滤泡的淋巴细胞是IBDV的主要靶细胞.接毒后ld,法氏囊滤泡就见有许多病毒;2～3d.病毒数量激增并达到高峰;4～5d,病毒数量维持较高水平;6～7d,病毒数量显著减少.本实验结果表明,BA法可以作为IBD的特异诊断方法,法氏囊可作为检测本病的首选器官,在法氏囊滤泡的髓质检出阳性淋巴细胞、阳性异染性白细胞和阳性巨噬细胞,或主要检出阳性巨噬细胞,均可作为本病的特异性诊断指标.     

Importance of the medullary macrophage in the replication of lymphoid leukosis virus in the bursa of Fabricius of chickens

Electron microscopy and immunocytochemistry were used to study the development of lymphoid leukosis virus infection in the bursa of Fabricius of experimentally infected chicken embryos and chickens. In embryos infected at 7 days of incubation and killed 10 days later, virus particles and group-specific viral antigen were confined mainly to the connective tissue of the lamina propria of the bursal mucosal folds; a few developing follicles had discrete virions and group-specific antigen between cells. In chickens infected at 1 day of age, infection (as determined by use of electron microscopy and immunocytochemistry) was maximal in 1- to 4-month-old birds, and the greatest concentration of virus and group-specific viral antigen was in the medulla of the follicles. Although lymphoid leukosis virus was released from lymphocytes, epithelial cells, and macrophages, virus replication in the medullary macrophages was more active than that in the other cells. Normal medullary macrophages had cell membrane vesicles (50 to 80 nm in diameter) that covered part of all of the cell membrane surface. In infected chickens, virus particles frequently developed within these vesicles. Comparable vesicles were not found on cortical macrophages. Results of the present study indicated that the medullary macrophage was the principal host cell for replication of lymphoid leukosis virus in the bursa of Fabricius of the chicken.     

人工感染IBDV鸡法氏囊的电镜研究

通过透射电镜系统观察了人工感染传染性法氏囊病病毒（ＩＢＤＶ）后鸡法氏囊各类细胞的病理变化。感染后１２￣２４ｈ，病毒粒子主要见于髓质淋巴细胞中，细胞中可见到大量纤维样病毒发生基质及无囊膜包围的大型病毒晶格，细胞核染色质浓缩，核中出现纤维样结构。感染后３６ｈ，淋巴细胞开始大量裂解死亡。无囊膜包围的病毒晶格也出现于髓质网状细胞中，被感染的网状细胞并不裂解，而表现出细胞凋亡的特征：染色质固缩呈颗粒块状，胞     

Pathogenesis of duck plague in the bursa of Fabricius, thymus, and spleen.

White Pekin ducks were inoculated orally with duck plague virus and killed at 24-hour intervals after inoculation. Spleen, thymus, and bursa of Fabricius were collected and examined by light, fluorescent, and electron microscopy. Necrosis of lymphocytes occurred in the bursa of Fabricius, thymus, splenic periarteriolar lymphoid sheath (T lymphocytes), and splenic germinal centers (B lymphocytes). Viral nucleocapsids were present in the karyoplasm of lymphocytes, but these cells necrotized before virions were formed. Periarteriolar reticular sheath cells and sinusoidal lining cells in the spleen, epithelial cells in Hassall's corpuscle of the thymus, epithelial cells between the cortex and medulla of the follicles in the bursa of Fabricius, and macrophages in all 3 tissues contained nucleocapsids in the nuclei and virions in cytoplasmic vacuoles before necrosis occurred.     

Sur l'Involution de la Bourse de Fabricius chez le Canard

On the involution of the bursa of Fabricius of the duck
The morphological and structural aspects of the functional aspects of the involution were studied light- and electronmicroscopically in ducks 90 to 150 days old. The first involutionary changes were observed in the interfollicular connective tissue around day 100. Following this, cells left the periphery of the follicles; they were connected with collagen fibers and positioned themselves between the lymphocytes of the cortex that became thinner before it disappeared.
On day 135 the medulla lost its lymphocyte content through wide ducts which opened directly into the lumen of the bursa. On day 150 the bursa experienced a massive overgrowth; almost all follicles had disintegrated and only small groups of cells remained which consisted principally of reticuloepithelial cells and some lymphocytes.
Cysts were not observed during the involution of the bursa.     

Recovery of antibody-producing ability and lymphocyte repopulation of bursal follicles in chickens exposed to infectious bursal disease virus.

We studied the long-term effect of infectious bursal disease virus (IBDV) in chickens. Specifically, the restoration of virus-induced bursal lesions and the duration of humoral immunodeficiency were examined. One-week-old specific-pathogen-free chickens were intraocularly inoculated with an intermediate vaccine strain (IBDV-Vac) or a virulent strain (IM-IBDV). At intervals postinoculation (PI), chickens were examined for histopathologic lesions. At 1, 3, 5, 10, or 15 wk PI, the chickens were injected with a mixture of antigens, and primary antibody responses were examined at 10 days postimmunization. Initially, the virus caused extensive necrosis of bursal B lymphocytes. This lesion was accompanied by an infiltration of T lymphocytes. With time, the necrotic lesion in the bursa was resolved. The follicles became partly repopulated with B lymphocytes. The repopulation occurred faster in the chickens exposed to IBDV-Vac than in the chickens exposed to IM-IBDV. By 7 wk PI, 40% and 80% of bursal follicles in IM-IBDV- and IBDV-Vac-inoculated chickens, respectively, were repopulated with immunoglobulin M+ B lymphocytes. Both IBDV-Vac and IM-caused suppression of the primary antibody response to antigens. However, the antibody responses of the chickens exposed to either of the two IBDV strains used were compromised only during the first 6 wk of virus exposure. Subsequently, the antibody response returned to near normal levels.     

Lymphocytic depletion of bursa of Fabricius and thymus in chickens inoculated with Escherichia coli

Specific-pathogen-free 10-week-old chickens were inoculated via the air sac with Escherichia coli and showed lymphocytic depletion of bursa of Fabricius and thymus. In experiment I, chickens were necropsied at 12 and 24 hours, 2, 3, and 5 days after inoculation. At 12 hours after inoculation there was lymphocytic depletion in the medulla of lymphoid follicles of the bursa. At 24 hours after inoculation there was lymphocytic depletion also in the cortex of follicles and edema in interfollicular interstitium and follicular medulla. At 2 and 3 days after inoculation there were more marked lymphocytic depletion in medulla and cortex, and fibrosis in interfollicular interstitium. Partial repopulation of follicles with lymphocytes was seen at 5 days after inoculation. In the thymus, lymphocytic depletion occurred in the cortex. At 12 hours after inoculation, lymphocytic necrosis increased in number more than that of control chickens. The width of the cortex and medulla decreased. At 24 hours after inoculation, lymphocytic necrosis increased further. At 2 to 5 days after inoculation, the boundary between the cortex and medulla of lobules was obscure and cellular elements of the cortex and medulla were mingled. In experiment II, chickens were necropsied as in experiment I and also at 8 and 14 days after inoculation. The relative weights of the bursa and thymus reduced rapidly to minimal relative weights at 8 days after inoculation. At 14 days after inoculation, both bursa and thymus had normal relative weights and histological structures. These findings indicate that E. coli infection may induce transient lymphocytic depletion of lymphoid tissues in the chicken.     

The Anatomy of the Cloacal Bursa (Bursa of Fabricius) in the Helmeted Guinea Fowl (Numida meleagris galeata)

The cloacal bursa (bursa of Fabricius) in the guinea fowls appeared either as an oval blind sac with a short thick stalk in one group or had a pointed cranial blind end with a slightly bulging middle part that was followed by a thick caudal stalk in the other group. Both groups of bursae originated from the proctodeal wall of the cloaca and were placed dorsal to the rectum. The average length of the bursa was 18 mm while the average width at die mid section was 15 mm. The internal surface showed about 12 – 14 primary folds. Histologically, the outline of the bursa was well established by day 18 of incubation. The primary folds had also been formed. Lymphocytes had already been encountered within the framework of the bursa at this day. The epithelium bordering the tunica propria was composed principally of two layers of cuboidal cells. Epithelial buds had also formed and some were already detached from the epithelial lining. The blood vessels present were positioned just beneath the outer covering. At day 19 of incubation, most of the epithelial buds had two layers of cells arranged in a circumscribed manner while a few had three layers of cells. Blood vessels had increased in number and were deeper placed inside the bursa than previously. At day 20, the cells of the upper layer of the epithelium were dorsoventrally flattened and stained paler than the cells of the lower layer. It was possible to distinguish the cortex from the medulla and the basement lining between both zones was distinct. Tiny vesicles within the cytoplasm of the epithelial cells at the mucosa and follicles were observed. Macrophges were also observed within the gland. At day 21, blood vessels were observed in the cortex of the follicles. The maximum number of primary folds (14) had been formed. At day 22, serveral follicles had severed connections with the mucosal epithelium. The mucosal lining had dropped to a single layer of cells in some areas. Goblet cells were observed amongst the mucosal cells. A plasma cell had first appeared. By day 25, dead cells had increased quite in number and there was also an increase in number of medium and small-sized lymphocytes within the gland. By day 26, the upper layer of the surface epithelium was composed primarily of tall columnar cells with numerous large vacuoles. Macrophages had suddenly increased within the thin interfollicu-lar spaces and most of them were crowded internally with various sizes of debris. By day one post-hatch, each fold was completely filled with follicles that were separated by thin connective tissue strands.     

Tissue tropism and bursal transformation ability of subgroup J avian leukosis virus in White Leghorn chickens

In Experiment 1, a monoclonal antibody against the envelope glycoprotein (gp85) of subgroup J avian leukosis virus (ALV-J) was used to study the distribution of ALV-J in various tissues of White Leghorn chickens inoculated as embryos with the strain ADOL-Hcl of ALV-J. At 2 and 6 wk of age, various tissues from infected and control uninfected chickens were tested for the presence of ALV-J gp85 by immunohistochemistry. In Experiment 2, using the methyl green-pyronine (MGP) stain, sections of bursa of Fabricius (BF) from chickens of line 15I5 x 7(1), inoculated with ALV-J or Rous-associated virus-1 (RAV-1), a subgroup A ALV, at hatch were examined for transformation of bursal follicles at 4 and 10 wk of age. In Experiment 1, specific staining indicative of the presence of ALV-J gp85 was noted at both 2 and 6 wk of age in the adrenal gland, bursa, gonads, heart, kidney, liver, bone marrow, nerve, pancreas, proventriculus, spleen, and thymus. In Experiment 2, by 10 wk of age, transformed bursal follicles were detected in MGP-stained sections of BF in only one of five (20%) chickens inoculated with ALV-J at hatch, compared with five of five (100%) chickens inoculated with RAV-1. The data demonstrate distribution of ALV-J gp85 in various tissues of White Leghorn chickens experimentally inoculated as embryos with the virus. The data also confirm our previous observation that ALV-J is capable of inducing transformation of bursal follicles, albeit the incidence is less frequent than that induced by subgroup A ALV.