Progressive changes in serum proteins and the rheumatoid factor of chickens infected with Mycoplasma synoviae.

Sera from controls and chickens infected with Mycoplasma synoviae were examined for serum protein content by cellulose-acetate electrophoresis, and for rheumatoid factor (RF) by a latex-agglutination test at 8, 18, 28, 38, and 48 days postinoculation (DPI). Mean total serum protein concentration was significantly elevated by 8 DPI and rose to much higher concentrations on each subsequent day of examination. The mean albumin concentration was significantly decreased by 8 DPI, and continued to decline to very low levels at 18 and 28 DPI, after which it began to rise and by 48 DPI did not significantly differ from the controls. The mean alpha-globulin concentrations were significantly elevated on all days of examination. The mean beta- and gamma-globulin concentrations were significantly elevated by 8 DPI and reached maximum levels at 18 DPI but remained elevated throughout the test. The percentage of chickens having RF titers increased on each successive examination day, but only 56% of the chickens had titers at 48 DPI.     

Histopathology of avian adenovirus group II splenomegaly of chickens

Chickens were infected with an avian adenovirus group II isolate previously obtained from chickens exhibiting splenomegaly in commercial broiler flocks. The isolate was inoculated orally in 6-week-old experimental chickens, which were euthanatized and necropsied 6 days postinoculation. The primary gross lesions found were splenomegaly and splenic mottling. Numerous tissues from 12 chickens were taken for histologic evaluation. Histologic lesions included splenic reticuloendothelial cell hyperplasia with intranuclear inclusions. Lymphocytic degeneration was seen in the lungs of most chickens examined. Lung hemorrhage and edema with endothelial disruption and congestion of pulmonary arterioles were found less frequently. The splenic lesions in the chickens were similar to those seen in turkeys naturally infected with hemorrhagic enteritis, and the lung lesions resembled those seen in pheasants naturally infected with marble spleen disease.     

Haemagglutination Inhibition Antibodies,Rectal Temperature and Total Protein of Chickens Infected with a Local Nigerian Isolate of Velogenic Newcastle Disease Virus

Changes in values of haemagglutination inhibition (HI) antibody titre, rectal temperature (RT) and total protein (TP) were determined for Shaver Brown chickens infected with Newcastle disease virus (NDV) Kudu 113. The infected chickens came down with Newcastle disease by day 3 post infection (PI). The major clinical signs were depression, greenish diarrhoea, paralysis of legs and wings, opisthotonus and torticolis. Mortality and morbidity were 52% and 1000%, respectively. There were haemorrhagic lesions in the wall of the intestine, proventricular mucosa and caecal tonsils. There were necrosis and mononuclear cell infiltration of the liver, kidney and spleen. There was a significant increase in daily mean HI antibody titres from days 3 to 9 PI. Similarly, significant rise in daily mean RTs were noticed in the infected chickens from days 1 to 13 PI. On the other hand, there was a decrease in daily mean TP concentrations of infected chickens, beginning from day 3 PI, and the lowest concentration of 2.60 +/- 0.15 g/dl was obtained by days 7 and 11 PI. The values of HI, RT and TP for the control chickens were relatively constant during the experiment. The correlation coefficient (r) between HI and RT was positive and highly significant (r = 0.725, p<0.001), while the relationship between HI and TP was negative but highly significant (r = -0.712, p<0.001). It was concluded that NDV Kudu 113 induced increases in values of HI and RT, which occurred concurrently with a decrease in TP concentrations of infected chickens.     

Hepatic lesions caused by migrating larvae of Ascaris suum in chickens

Group A consisted of chickens infected with a single dose of Ascaris suum and group B of chickens infected with two successive doses. At days 1, 3, 7, 14 and 21 after the first or second infection dose, six chickens from each group were sacrificed. In both groups, larvae were recovered from the livers on days 1, 3, and 7 and lungs on days 3 and 7. No larvae were detected in chickens on day 14. Clear white lesions were noticed only on the livers from chickens of group B at day 7 but had disappeared at day 14. A comparison with group B showed mild histological changes that developed relative to the livers from group A.     

Correlation of hematological changes and serum and monocyte inhibition with the early suppression of phytohemagglutinin stimulation of lymphocytes in experimental infectious bursal disease.

Several experiments were conducted to study the mechanism of infectious bursal disease virus induced suppression of phytohemagglutinin stimulation of peripheral blood lymphocytes. Infectious bursal disease virus inoculation of one week old chicks resulted in significant suppression of phytohemagglutinin stimulation during the first three days after inoculation as demonstrated by a whole blood assay. Mild thymic necrosis was seen on day 3. Hematological changes during this time consisted of increased numbers of circulating lymphocytes and monocytes in infected chickens. Absolute monocyte counts remained elevated even after phytohemagglutinin stimulation had returned to normal. Furthermore, even after a 72.3% reduction in the monocyte population in leukocyte preparations, there was still marked viral induced suppression of phytohemagglutinin stimulation. An elevation in the absolute number of circulating large immature lymphocytes correlated with suppression of phytohemagglutinin stimulation. Sera from infected and control chickens depressed phytohemagglutinin stimulation of lymphocytes from control chickens at the 5 and 10% concentration. At the 1% concentration, inhibiton by control sera was considerably less than the inhibition by infected sera. The relationship between these findings and the mechanism of viral induced suppression of T-lymphocyte function is discussed.     

Detection of antibodies to the nonstructural protein (NS1) of avian influenza viruses allows distinction between vaccinated and infected chickens

To differentiate avian influenza virus (AIV)-infected chickens vs. chickens immunized with inactivated avian influenza virus, an enzyme-linked immunosorbent assay (ELISA) was developed using a recombinant nonstructural protein (NS1) as the diagnostic antigen, which was cloned from an AIV H9N2 subtype strain isolated during the avian influenza outbreak of 2003-04 and expressed in Escherichia coli. Antibodies to the AIV NS1 protein was only detected in the sera of chickens experimentally infected with AIV but not in the sera of chickens immunized with inactivated vaccine. This ELISA is useful for serological diagnosis to distinguish chickens infected with influenza viruses from those immunized with inactivated vaccine.     

Blood cells and plasma proteins of chickens fed a diet supplemented with (1-->3),(1-->6)-beta-D-glucan and enrofloxacin.

The effects of (1-->3),(1-->6)-beta-D-glucan from Saccharomyces cerevisiae and of the fluochinolone enrofloxacin were studied on red and white blood cells and plasma proteins of growing chickens up to the 35th day of life. The prominent findings within the leukocyte population on a per cent scale are: (i) increase of leukocyte count; increase of neutrophils and decrease of lymphocytes in the control and in the antibiotic group from day 17 to day 35; (ii) a minor decrease of neutrophils and no change of lymphocytes in the glucan group; (iii) the monocytes increase from 2.5 +/- 1.8% to 6.5 +/- 7.6% in the glucan group; (iv) the basophils increase in the control group and scale down in the other groups from day 17 to day 35. The total count of leukocytes increases in the controls and in the glucan group. The total protein content of blood plasma, beta-globulin and gamma-globulin increase and the albumin-globulin-ratio and alpha-globulin decline during chickens growth. These changes are most prominent in the glucan group. The haemoglobin concentration shows in all three dietary groups a highly significant increase from day 17 to day 35 by about 17 to 27 per cent; no changes are seen in packed cell volume and number of erythrocytes per litre blood.     

The humoral immune response of chickens to Mycoplasma gallisepticum and Mycoplasma synoviae studied by immunoblotting

The humoral immune response over time of White Leghorn chickens experimentally infected with Mycoplasma gallisepticum or M. synoviae by an aerosol inoculation or a contact exposure were compared by immunoblotting. The response of chickens infected with M. gallisepticum were similar with respect to proteins recognized and intensity of response, regardless of mode of infection. On the other hand, chickens infected by aerosolization of M. synoviae responded to more proteins and with greater intensity than did M. synoviae contact-exposed birds. Chickens infected with M. gallisepticum responded with antibodies to over 20 proteins, while chickens infected with M. synoviae responded with antibodies to 12 proteins. Field sera from chickens naturally infected on commercial poultry farms with M. gallisepticum or M. synoviae were analyzed by immunoblotting and were found to react with a number of mycoplasma proteins. However, no correlation was seen when comparing intensity of immunoblot staining and hemagglutination-inhibition titer of the field sera. The experimental antisera were used to identify species-specific proteins of M. gallisepticum and M. synoviae. Six immunogenic species-specific proteins of M. gallisepticum with relative molecular masses of 82 (p82), 65-63 (p64), 56 (p56), 35 (p35), 26 (p26), and 24 (p24) kilodaltons (kDa) were identified. Two species-specific proteins of M. synoviae with relative molecular masses of 53 (p53) and 22 (p22) kDa were identified. Additionally, a highly immunogenic 41 (p41) kDa protein of M. synoviae was identified. Species-specific proteins identified in these mycoplasmas and the 41 kDa protein of M. synoviae were purified by preparative SDS-PAGE in amounts sufficient for further characterization and for use in serodiagnostic tests.     

SIMULATED NATURAL INFECTION OF CHICKENS WITH AUSTRALIAN LENTOGENIC NEWCASTLE DISEASE VIRUS AND SUBSEQUENT CHALLENGE WITH VIRULENT VIRUS

A total of 291 eight-week-old chickens were exposed to chickens infected with either of two Australian lentogenic strains (V4 and AVL NDV-1) of Newcastle disease virus (NDV). At 3 weeks after exposure, all chickens exposed to V4 infected chickens had developed haemagglutination-inhibition (HI) antibody. All chickens exposed to AVL NDV-1 virus infected chickens had developed HI antibody 5 weeks later. This sudden late appearance of HI antibody, to titres higher than those observed with V4 chickens, was explained by V4 virus being introduced to the AVL NDV-1 group of chickens. When groups of these chickens were challenged with Roakin virus (mesogenic NDV) at 3 weeks and Fontana 1083 virus (viscerotropic velogenic NDV) and Texas GB virus (neutrotropic NDV) at 3, 5, 10 and 21 weeks only three chickens developed clinical illness one of which died. These chickens were one AVL NDV-1 chicken contact challenged with Fontana 1083 virus at 3 weeks, one V4 chicken oronasally challenged with Texas GB virus at 5 weeks and one V4 chicken challenged oronasally with Fontana 1083 virus at 10 weeks. Susceptible non-vaccinated chickens died soon after challenge. Challenge by oronasal infection with 10(7.0) ELD50 of virus or contact with susceptible infected chickens enabled virulent virus to be isolated from most chickens and was accompanied by a large anamnestic increase in serum HI antibody.     

感染CAA雏鸡ND免疫后三种体液中HI抗体变化

对１日龄感染ＣＡＡ雏鸡接种Ｌａｓｏｔａ弱毒疫苗后，其血清、泪液、胆汁中ＨＩ抗体滴度的变化进行了研究。结果发现，感染ＣＡＡ雏鸡Ｌａｓｏｔａ疫苗免疫后，三种体液中ＨＩ抗体滴度明显低于未感染ＣＡＡ的照雏鸡。     

Different routes of inoculation impact infectivity and pathogenesis of H5N1 high pathogenicity avian influenza virus infection in chickens and domestic ducks

The H5N1 type A influenza viruses classified as Qinghai-like virus (clade 2.2) are a unique lineage of type A influenza viruses with the capacity to produce significant disease and mortality in gallinaceous and anseriform birds, including domestic and wild ducks. The objective of this study was to determine the susceptibility and pathogenesis of chickens and domestic ducks to A/Whooper Swan/Mongolia/224/05 (H5N1) high pathogenicity avian influenza (HPAI) virus when administered through respiratory or alimentary routes of exposure. The chickens and ducks were more susceptible to the H5N1 HPAI virus, as evidenced by low infectious and lethal viral doses, when exposed by intranasal as compared to alimentary routes of inoculation (intragastric or oral-fed infected chicken meat). In the alimentary exposure pathogenesis study, pathologic changes included hemorrhage, necrosis, and inflammation in association with virus detection. These changes were generally observed in most of the visceral organs of chickens, between 2 and 4 days postinoculation (DPI), and are similar to lesions and virus localization seen in birds in natural cases or in experimental studies using the intranasal route. Alimentary exposure to the virus caused systemic infection in the ducks, characterized by moderate lymphocytic encephalitis, necrotized hepatitis, and pancreatitis with a corresponding demonstration of virus within the lesions. In both chickens and ducks with alimentary exposure, lesions, virus, or both were first demonstrated in the upper alimentary tract on 1 DPI, suggesting that the alimentary tract was the initial site affected upon consumption of infected meat or on gavage of virus in liquid medium. However, as demonstrated in the infectivity study in chickens, alimentary infection required higher exposure doses to produce infection as compared to intranasal exposure in chickens. These data suggest that upper respiratory exposure to H5N1 HPAI virus in birds is more likely to result in virus infection and transmission than will consumption of infected meat, unless the latter contains high doses of virus, as found in cannibalized infected carcasses.     

H9亚型禽流感病毒感染鸡生理指标的分析

通过测定H9亚型禽流感发病鸡群及健康鸡群的某些生化指标,发现H9亚型禽流感疾病状态下皮质醇激素、甲状腺激素和血清钙的水平均与健康鸡群差异显著,而生长激素和血清磷无明显差异.这些变化是由于机体对疾病的抵抗或代谢紊乱产生的,可以作为疾病诊断的依据.     

Nephropathogenesis of chickens experimentally infected with various strains of infectious bronchitis virus

Four-day-old specific-pathogen-free chickens were inoculated by eyedrop with four different strains (Gray, JMK, CV56b, and Wolgemuth) of infectious bronchitis virus (IBV). Birds were monitored clinically and euthanatized at 1, 4, 7, and 14 days postinfection and tissues were collected for virus isolation, histopathologic examination, in situ hybridization (ISH), and immunohistochemistry (IHC). Clinical disease was severe in chickens infected with Wolgemuth, but no overt disease was observed with the other strains. Virus was isolated from the kidneys of chickens infected with the Gray-, CV56b-, and Wolgemuth-strains of IBV. Histologically, interstitial nephritis was evident in chickens infected with these same 3 strains. However, viral nucleic acid and antigen were detected only with Wolgemuth-infected kidneys by ISH and IHC. These results indicate that the pathological changes in kidneys from chickens infected with Gray and CV56b may not have resulted from the cytolytic action of the virus.     

Experimental induction of the cutaneous form of Marek's disease in broilers

Straight-run chickens of the Ross broiler hybrid were experimentally infected with the skin homogenates of sound broilers, broilers conditionally edible, and broilers confiscated for alternations in skin. The chickens infected with the homogenates of healthy skin were negative in the Marek's disease test. In 17% of the chickens infected with the skin from the conditionally edible broilers, macroscopically observable cutaneous lesions were induced and 60% of the infected chickens had microscopic changes in the skin; visceral organs were always affected by the infection. In the chickens infected with the skin of a confiscated bird, the long storage exerted its unfavourable effect and the infected birds were negative in the Marek's disease test. Our results indicate that the active form of Marek's disease was induced.     

ChMDA5通路参与传染性法氏囊病病毒致雏鸡法氏囊损伤的研究

传染性法氏囊病病毒（IBDV）为dsRNA病毒,可造成雏鸡法氏囊损伤进而发生免疫抑制;MDA5是能够特异性识别dsRNA病毒的模式识别受体。为研究鸡MDA5（chMDA5）信号通路在IBDV致雏鸡法氏囊病理损伤中的作用,试验选取50只14日龄SPF雏鸡随机分为IBDV感染组和空白对照组,每组25只,IBDV感染组雏鸡通过点眼、滴鼻感染IBDV JIC7株病毒液,0.6 mL·只^-1,空白对照组雏鸡经相同途径给予相同剂量无菌PBS,感染IBDV后第1、4、7、21及35天采集雏鸡法氏囊。采用qRT-PCR方法检测法氏囊中IBDV载量,chMDA5及chMDA5信号通路衔接蛋白（chIPS-1）、转录因子（chIRF3和chNF-κB）、下游产物细胞因子（chIFN-β、chTNF-α、chIL-1β、chIL-6） mRNA水平变化;间接免疫荧光法检测chMDA5蛋白表达变化,传统病理学方法检查法氏囊病理组织学变化。结果发现,雏鸡感染IBDV后,其法氏囊中chMDA5、chIPS-1、chIRF3、chNF-κB、chIFN-β、chTNF-α、chIL-1β、chIL-6的表达量均显著高于对照组,且法氏囊组织发生形态损伤,上述变化趋势与IBDV载量变化基本一致。结果表明,雏鸡法氏囊chMDA5及其信号转导通路可被IBDV激活,参与到IBDV感染雏鸡法氏囊损伤与抗损伤过程中。     

Detection of the meq gene in the T cell subsets from chickens infected with Marek's disease virus serotype 1

The meq gene was thought to be only detected in Marek's disease virus serotype 1 (MDV 1) including a very virulent strain, Md5, while L-meq, in which a 180-bp sequence is inserted into the meq open reading frame, is found in other strains of MDV 1, such as CVI 988/R6. However, both meq and L-meq were previously detected by PCR in chickens infected with MDV 1, suggesting that MDV 1 may consists of at least two subpopulations, one with meq, the other with L-meq. To further analyze these subpopulations, we analyzed the time course changes in distribution of these subpopulations among T cell subsets from chickens infected with MDV 1. Both meq and L-meq were detected in CD4+ and CD8+ T cells infected with strain Md5 or CVI 988/R6. The shift in MDV subpopulations from one displaying meq to the other displaying L-meq and/or the conversion from meq to L-meq occurred mainly in the CD8+ T cell subset from Md5-infected chickens. PCR products corresponding to L-meq rather than meq were frequently amplified from the CD8+ T cell subset from CVI 988/R 6 -infected chickens. These results suggest that a dominant subpopulation of MDV 1 changes depending on the T cell subsets, and that L-meq is dominantly present in the CD8+ T cells which play a role in the clearance of pathogenic agents.     

Reduced serologic response to Newcastle disease virus in broiler chickens exposed to a Chinese field strain of subgroup J avian leukosis virus

In this study, a Chinese field strain of subgroup J avian leukosis virus (ALV-J), NX0101, was studied for its immunosuppressive effects in both commercial broilers and SPF white Leghorn chickens infected at 1 day of age. Our data demonstrated that NX0101 induced much more significant body and immune organ weight loss in the infected commercial broiler chickens in an earlier age than that in the SPF white Leghorn chickens. At the same time antibody responses to vaccinations of Newcastle disease virus (NDV) and infectious bursa disease virus (IBDV) in the NX0101-infected chickens were also evaluated and compared between the commercial broiler chickens and the SPF white Leghorn chickens. Compared with the control group of chickens, the hemagglutination inhibition (HI) antibody response to NDV vaccines was significantly reduced in the NX0101-infected commercial broiler chickens from as early as 20 days after vaccination. However, no significant difference in HI antibody response was seen when HI titers reached their peaks in the NX0101-inoculated and control SPF white Leghorn chickens, except it declined significantly faster in infected birds. Neither of these two types of chickens showed significant decrease of antibody response to IBDV vaccination. Herein, we conclude that this NX0101 strain of ALV-J could selectively suppress humoral immune reactions to NDV, especially in broilers. But challenge experiments were not conducted and, therefore, it cannot be known if decreased antibody levels correlated with decreased protection against NDV in this case.     

鸡腺胃病变型传染性支气管炎病毒感染试验

本文采用腺胃病变型传染性支气管炎患病鸡的腺胃病料和H95株分离株尿囊液毒,对不同品种、不同日龄的易感鸡,采用不同的感染途径进行感染,对其增重、死亡等数据进行统计分析,结果表明:供试不同品种的鸡在不同的感染途径下,采用腺胃病料和鸡胚尿囊液毒分别感染,均可引起不同程度的感染发病,并出现和自然病例相同的症状和典型的病理变化。随日龄的增长,其易感率和死亡率呈下降趋势。从感染死亡鸡中可重新回收到相应的病毒,发病耐过的鸡可产生特异性抗体。     

Proteins and antigens of Pasteurella multocida serotype 1 from fowl cholera.

The protein profiles of Pasteurella multocida serotype 1 isolates and the response of chickens to serotype 1 antigens were investigated using SDS-PAGE. Patterns obtained with Coomassie blue staining of soluble protein extracts were similar. The major difference between isolates was the position of one of the major proteins in the 34-38 kDa region. When chickens were experimentally infected with a clinical isolate of P. multocida serotype 1 various proteins were recognised by immunoblotting, including one with a relative molecular weight of 34 kDa; however, no reactions were observed in the region where LPS is known to migrate. When these infection sera were used in an EIA with purified LPS obtained from Heddleston serotype 1 type strain (X-73) they reacted strongly. Serum used for serotyping isolates in the gel diffusion precipitin test recognised many antigens in common with sera from infected birds, but some antigens were specific to typing sera.