Digestion in the crop of the fowl

Examination of the crop contents of fowls has shown that there is extensive hydrolysis of starch to sugar and that much of the sugar formed can be lost from the crop by absorption by the crop, the action of micro‐organisms or leaching from the crop. When crop contents were incubated anaerobically, lactic and acetic acids and alcohol were produced. Examination post‐mortem of crop contents from birds with “sour crops” indicated that, in addition to the formation of lactic and acetic acids, formic, propionic and butyric acids can also be formed.     

鸡源新城疫病毒人工感染鸭的病理组织学研究

本研究取120只20日龄健康非免疫建湖鸭,随机分为2组,每组60只,研究鸡源新城疫病毒人工感染鸭的病理组织学变化及其病理演变过程。试验组皮下接种1：5稀释的鸡源新城疫病毒分离株（WF00G株）SPF鸡胚绒尿液毒0．5mL／只,对照组皮下注射等量灭菌生理盐水,隔离饲养,临床观察20d。于攻毒后第4d、8d、12d、16d、20d每组各取鸭4只,颈动脉放血致死,解剖观察心脏、肝、脾、肺、肾等器官的病变,取材制作石蜡切片及超薄切片,观察病理组织学变化。结果显示：试验鸭胸腺点状出血;心脏体积增大、心肌柔软、心包积液;肝脏肿大,质地变脆;肺脏出血;肾脏明显肿大。病理组织学变化主要为肝、脾、肺及肾等器官出血,细胞变性、坏死,细胞器溶解等。研究结果表明鸡源新城疫病毒WF00G株人工感染鸭可致鸭发病,临床症状较轻微,剖检病变和组织学病变明显。     

支原体肺炎大鼠肺组织病理学的实验观察

肺炎支原体(mycoplasma pneumoniae，MP)为介于细菌和病毒之间的原核细胞型微生物，是引起支原体肺炎的重要致病菌。主要经飞沫和气溶胶传人呼吸道黏膜，首先引起上呼吸道感染，然后下行感染引起气管炎、支气管炎、细支气管炎和肺炎。同时引起多系统肺外并发症，病程长，病情重，甚至引     

Genital lesions and histopathology of male guinea-pigs infected with trypanosomes.

Sixty adult male guinea-pigs were used to study the effect of Trypanosoma brucei brucei and Trypanosoma congolense infections on genitalia, testicles and reproductive capacity. Both infections showed acute to chronic courses. T. b. brucei appeared more virulent than T. congolense. In both cases the infection periods significantly (P < 0.01) influenced resultant decrease in body and gonadal weight, testicular mass index and extent of lesion formation. Histopathological lesions included mononuclear infiltration, distortion of seminiferous tubules and degeneration of germ cells. Both trypanosomes impaired reproductive capacity through impaired hormone biosynthesis, sperm production and reserves. Use of guinea-pigs as a laboratory model for the study of trypanosomosis in domestic animals is discussed.     

Pathological changes of tracheal mucosa in chickens infected with fowl pox virus

Five-week-old chickens were inoculated with fowl pox (FP) virus and killed on various days through day 30 postinoculation (PI). The trachea was examined with a scanning electron microscope (SEM), a transmission electron microscope (TEM), and a light microscope (LM). From day 3 PI, small focal lesions of the mucosa were detected. On day 7 PI, upon formation of cytoplasmic inclusion bodies, epithelial cells proliferated profusely, enlarged, and formed clusters like papillomata. The disease proceeded to the gradual disruption of the lesions owing to the collapse of individual degenerating epithelial cells. Total desquamation of the lesions was observed. Ultrastructural examination revealed that the surface degenerating epithelial cells of the lesions ruptured and had virus particles inside. These changes were accompanied by severe inflammatory reaction. Thereafter, epithelial cells regenerated actively and the mucosa recovered by day 27 PI.     

育雏早期应用氟苯尼考对禽腺病毒感染雏鸡病情的影响

为了评价氟苯尼考的应用对禽腺病毒感染雏鸡病情的影响,本试验通过对血清4型禽腺病毒感染SPF雏鸡并应用氟苯尼考饮水给药,监测雏鸡的发病及排毒情况,并对免疫器官指数、干扰素相关基因及细胞因子基因表达情况进行检测.结果显示,病毒感染雏鸡后应用氟苯尼考能显著增加雏鸡的病死率及排毒量,加重雏鸡的病理学变化,并降低雏鸡免疫器官指数...     

Haematological changes in domestic fowl experimentally infected with the cestode Raillietina tetragona (Molin, 1858)

Haematological alterations in domestic fowl following three levels of infection with 20, 50 and 100 cysticercoids of Raillietina tetragona (Eucestoda) have been studied over a period of 8 weeks. The infected birds showed significant haemoglobin depression. There was no significant change in the packed cell volume (PCV), RBC counts or mean corpuscular haemoglobin (MCH). In all three levels of infection, the calculated mean corpuscular volume (MCV) increased, while the mean corpuscular haemoglobin concentration (MCHC) decreased considerably. Macrocytic anaemia along with hypochromia could be noticed during different periods of infection. Total white cell count diminished significantly in infected birds. There was a significant lymphocytopenia concurrent with a significant increase in the percentage of heterophilic elements. Eosinophilia was not a consistent feature. Erythrocyte sedimentation rate (ESR) increased significantly in infected birds. The changes in the blood picture were more pronounced in birds infected with 50 and 100 cysticercoids.     

The aetiology and significance of the phagocytosis of erythrocytes and leucocytes in sheep infected with Trypanosoma congolense (Broden, 1904).

The phagocytosis of erythrocytes and leucocytes in sheep infected with Trypanosoma congolense is shown to be due to the coating of the blood cells with trypanosomal antigen. The occurrence of the phagocytic activity is dependent on fluctuations of the parasitaemia and is significant in maintaining the anaemic state of the subject.     

鸭瘟病毒强毒株感染SPF鸭后动态病理组织学变化

用鸭瘟病毒(Duck plague virus,DPV)人工感染2月龄SPF鸭,定期剖杀,经聚合酶链反应(PCR)检测为鸭瘟后,对各组织器官的病理组织学变化进行观察,并进行血常规和血液生化指标检测.结果显示,人工感染后24 h,试验鸭中枢免疫器官胸腺、法氏囊表现为淋巴细胞数量减少,组织间隙增大;肝脏、脾脏组织病变较为严重,大部分组织器官均出现程度较轻的病理变化.感染后48～96 h,中枢免疫器官的淋巴细胞极度减少、网状细胞增生、组织器官结构模糊不清,严重充血、出血;其余组织器官出现细胞变性、出血等不可逆病理变化.感染后120 h,组织细胞变性、坏死,出现大片坏死区.点眼滴鼻组鸭感染DPV后组织学变化与皮下注射组相似,只是发生的时间偏后约24～48 h.对照组鸭病理组织学观察未见损伤.WBC、HGB、AST、ALT等发生显著变化.结果表明,接种DPV强毒感染鸭的组织器官严重受损,特别是免疫器官,甚至会引起免疫抑制.     

Comparative histopathology in BALB/c mice infected with virulent and attenuated strains of Brucella abortus

The course of infection in BALB/c mice of virulent Brucella abortus strain 2308 (S-2308) and attenuated strain 19 (S-19) varies markedly. Whereas S-19 is eliminated at an exponential rate beginning at 2 weeks post infection (p.i.), strain 2308 assumes a steady state or plateau during the first 6 weeks p.i. and thereafter is eliminated very slowly over a period exceeding 6 months. Here we compared the initiation and maintenance of inflammatory reactions in spleens and livers of mice infected with either of the two strains of B. abortus for the first 6 weeks p.i. Histological changes in the liver were similar in response to either strain and were characterized by the development of small granulomas and an influx of polymorphonuclear leukocytes (PMN) and monocytes. Tissue reactions in the spleen were similar at weeks 1 and 2 p.i. At 3 weeks p.i. and thereafter, focal granulomatous responses in S-2308-infected mice exceeded those in mice infected with S-19. Numbers of nonspecific esterase (NSE) positive mononuclear leukocytes in S-19-infected spleens had increased by 3 weeks p.i. and remained elevated. No comparable increase in NSE positive cells occurred in mice infected with S-2308, and numbers were significantly lower. At 4 weeks p.i. the influx of mature neutrophils and the intensity of extramedullary hematopoiesis were significantly greater in S-19-infected spleens. A profound depletion of periarteriolar lymphoid tissue was noted in both infections for the first 3 weeks p.i. However, repopulation of lymphoid sheaths in S-19-infected spleens became significantly greater by 4 weeks p.i. and continued to increase at significantly higher levels during the next 2 weeks. This study demonstrates quantitative differences in splenic inflammatory responses which are temporally related to the more rapid elimination of S-19. Based upon the lower susceptibility of strain 2308 to the protective effects of immune serum it is hypothesized that the different patterns of infection and inflammation displayed by the 2 strains may related to the differential capacities of antibody opsonized S-19 and S-2308 to survive in activated macrophages.     

Serological examination and egg production of progeny of fowl experimentally infected with Egg Drop Syndrome 1976 virus

Summary

Following EDS'76 virus (BC14 virus) infection of breeder chickens by the conjunctival route, vertical transmission occurred in the first week after infection. In the progeny which had been infected with EDS'76 virus by the vertical route, increasing haemagglutination inhibiting (HI) litres to BC14 virus and increasing numbers of birds with HI litres were observed from 3 weeks to 15 weeks of age. Sixty‐one per cent of the hens and 77 per cent of the cocks had ²log HI BC14 virus litres exceeding 4 at an age of 15 weeks.

Some birds which had been serologically negative throughout the rearing period, seroconverted between 25 and 28 weeks of age. This phenomenon occurred in hens as well as in cocks. Simulation of stress twice during the laying period by injection of corticosteroid hormone did not increase the number of birds serologically positive to EDS'76 virus.

EDS'76 was observed in the group of hens that was vertically infected, since egg production was significantly depressed between 28 and 34 weeks of age. Probably this was mainly the result of a production drop in the hens showing seroconversion at 27 or 28 weeks of age.

In the group of fowl vertically infected with EDS'76 virus, serologically positive birds appeared to be protected for the greater part to BC14 virus challenge at 50 weeks of age, while negative birds seemed to be fully susceptible. Chicks hatched from eggs collected in the third and fourth week after infection of the dams had maternal antibodies. Fertility and hatchability of apparently normally shelled eggs seemed not to be affected after BC14 virus infection of the dams. Intensive contact with contaminated faeces is probably an indispensable condition for lateral transmission of the virus.     

Serological examination and egg production of progeny of fowl experimentally infected with egg drop syndrome 1976 virus

Following EDS'76 virus (BC14 virus) infection of breeder chickens by the conjunctival route, vertical transmission occurred in the first week after infection. In the progeny which had been infected with EDS'76 virus by the vertical route, increasing haemagglutination inhibiting (HI) titres to BC14 virus and increasing numbers of birds with HI titres were observed from 3 weeks to 15 weeks of age. Sixty-one per cent of the hens and 77 per cent of the cocks had 2 log HI BC14 virus titres exceeding 4 at an age of 15 weeks. Some birds which han been serologically negative throughout the rearing period, seroconverted between 25 and 28 weeks of age. This phenomenon occurred in hens as well as in cocks. Simulation of stress twice during the laying period by injection of corticosteroid hormone did not increase the number of birds serologically positive to EDS'76 virus. EDS'76 was observed in the group of hens that was vertically infected, since egg production was significantly depressed between 28 and 34 weeks of age. Probably this was mainly the results of a production drop in the hens showing serconversion at 27 or 28 weeks of age. In this group of fowl vertically infected with EDs'76 virus, serologically positive birds appeared to be protected for the greater part to BC14 virus challenge at 50 weeks of age, while negative birds seemed to be fully susceptible. Chicks hatched from eggs collected in the third and fourth week after infection of the dams had maternal antibodies. Fertility and hatchability of apparently normally shelled eggs seemed not to be affected after BC14 virus infection of the dams. Intensive contact with contaminated faeces is probably an indispensable condition for lateral transmission of the virus.