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PCR Based Evidence of Reticuloendotheliosis Virus Infection in Chickens from Turkey  [PDF]
Hasan Ongor and Hakan Bulut1*
Pakistan Veterinary Journal , 2011,
Abstract: In this study, presence of avian leukosis virus (ALV) and reticuloendotheliosis virus (REV) was investigated in neoplastic cases observed in breeder hens older than 20 weeks in commercial broiler breeders. Tumor samples were examined by PCR combined with primer sets specific for ALV and REV. It was found that the tumors were REV-originated. This is the first report showing the presence of REV infection in Turkey.
Detection of fowl poxvirus integrated with reticuloendotheliosis virus sequences from an outbreak in backyard chickens in India  [PDF]
Sanchay K. Biswas,Chandrakanta Jana,Karam Chand,Waseem Rehman
Veterinaria Italiana , 2011,
Abstract: Fowl poxvirus (FPV) infection was observed in unvaccinated backyard chickens. A total of 15 birds were affected in a flock of 37. Pock lesions were observed on the comb, eyelids, beak and wattles. The birds appeared sick with roughened feathers and stunted growth. No mortality was recorded. DNA was isolated from scabs and polymerase chain reaction (PCR) was performed to amplify the 4b core protein gene of FPV, the envelope (env) gene of reticuloendotheliosis virus (REV) and the region of FPV flanking REV 5 ′ long terminal repeat (LTR). Correct-size PCR products of 578 bp, 807 bp and 370 bp, respectively, were observed in agarose gel electrophoresis. Sequence analysis of these products suggests that the virus was an FPV with a genome containing an integrated near full-length REV provirus. Given the fact that REV has been associated with immunosuppression, its presence in the genome of FPV appears to play an important role in the pathogenesis of fowl pox and presumably prolongs persistence of FPV in bird populations. In the present case, fowl pox has been observed to have persisted for about three years in fowl that were reared in backyard systems in villages.
Immunogenicity of envelope glycoprotein gene of reticuloendotheliosis virus expressed in insect cell

WANG Xi-le,ZHANG Zhi,JIANG Shi-jin,CUI Zhi-zhong,

微生物学报 , 2005,
Abstract: A recombinant baculovirus expressing reticuloendotheliosis virus env gene was constructed with Bac-to-Bac Baculovirus Expression Systems. After transfecting the recombinant virus into Sf9 cells for 3 days, REV env can be detected by indirect immunofluorescence antibody assay (IFA) and Western blot with specific monoclonal antibodies of REV. The oil-water emulsion vaccine was then produced using this infected Sf9 cells lycates and inoculated SPF chickens to validate the immunogenicity for REV. The results show that special anti-REV antibody can maintain more than 45 days and resist the infection of REV viruses. This is the first success to induce anti-REV antibody in chickens by none-live viruses.
Infectious bursal disease virus: case report and experimental studies in vaccinated and unvaccinated SPF chickens and commercial broiler chicks
Scanavini Neto, H;Ito, NMK;Miyaji, CI;Lima, E de A;Okabayashi, S;Corrêa, ARA;Eleutério, GC;Zuanaze, MA;
Revista Brasileira de Ciência Avícola , 2004, DOI: 10.1590/S1516-635X2004000100006
Abstract: ibdv gm 11 (simbios eleven-molecular group) has been detected since 1997 in many farms of commercial broilers and layers causing high mortality (2 to 15%) and severe macro and microscopic damage in cloacal bursae, spleen, thymus, kidney and liver. five serial passages of 2050/97-gm 11 ibdv sample by cam route in spf chicken's embryonated eggs did not elicit increased embryo mortality. high mortality (100%) of 21 day-old spf leghorn chickens and severe bursal and splenic lesions were seen from 24 up to 48 hours after eye-drop inoculation of 2050/97 strain (50 ml of 10-2 dilution of 10% bursae homogenate). mortality was not detected when vaccinated spf and broiler chickens were inoculated. one dead bird was found among ten challenged unvaccinated broilers. variations in the intensity of cloacal bursae injury and spleen response were found between unvaccinated and vaccinated broiler chickens. ibdv antibodies were detected by elisa test in almost all vaccinated spf chickens before challenge while low number of commercial vaccinated and unvaccinated broilers were serologically positive (0 to 3 birds in 18). increasing ibdv antibody titers were detected after challenge with 2050/97 strain and highest gmts were found in broilers. it was concluded that 2050/97 strain is a highly virulent ibdv and spf leghorn chickens immunized with bv8 intermediate vaccine strain were resistant to the challenge. increasing susceptibility was found from experimental groups of unvaccinated broilers to vaccinated broilers and to unvaccinated spf birds. it is discussed that passive immunity was involved in the rate of protection of challenged unvaccinated broiler and in the immune response impairment after vaccination of broilers chicks. the use of a constant virus suspension with known potency to challenge the experimental birds was suitable to evaluate vaccination efficacy. evaluation of bursal and splenic responses at early and delayed time after challenge were useful to estimate vaccination
Detection of Infectious Laryngotracheitis Virus by Real-Time PCR in Naturally and Experimentally Infected Chickens  [PDF]
Yan Zhao, Congcong Kong, Xianlan Cui, Hongyu Cui, Xingming Shi, Xiaomin Zhang, Shunlei Hu, Lianwei Hao, Yunfeng Wang
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0067598
Abstract: Infectious laryngotracheitis (ILT) is an acute, highly contagious upper-respiratory infectious disease of chickens. In this study, a real-time PCR method was developed for fast and accurate detection and quantitation of ILTV DNA of chickens experimentally infected with ILTV strain LJS09 and naturally infected chickens. The detection lower limit of the assay was 10 copies of DNA. There were no cross reactions with the DNA and RNA of infectious bursal disease virus, chicken anemia virus, reticuloendotheliosis virus, avian reovirus, Newcastle disease virus, and Marek's disease virus. The real-time PCR was reproducible as the coefficients of variation of reproducibility of the intra-assay and the inter-assay were less than 2%. The real-time PCR was used to detect the levels of the ILTV DNA in the tissues of specific pathogen free (SPF) chickens infected with ILTV at different times post infection. ILTV DNA was detected by real-time PCR in the heart, liver, spleen, lung, kidney, larynx, tongue, thymus, glandular stomach, duodenum, pancreatic gland, small intestine, large intestine, cecum, cecal tonsil, bursa of Fabricius, and brain of chickens in the infection group and the contact-exposure group. The sensitivity, specificity, and reproducibility of the ILTV real-time PCR assay revealed its suitability for detection and quantitation of ILTV in the samples from clinically and experimentally ILTV infected chickens.
Experimental Study of Renal Tubular Cells Apoptosis Subsequent to Infectious by Influenza Virus (H9N2) in SPF Chickens
Yousef Doustar,Daryoush Mohajeri,Younes Anzabi,Mehrdad Nazeri
International Journal of Poultry Science , 2011,
Abstract: Influenza virus produces cell death in animals and human. Since cell death can be caused by either necrosis or apoptosis. We investigated the types of cell death that occur in chickens infected with avian influenza virus, A/chicken/Iran/772/2000(H9N2). In experimental study 60 SPF chickens at 3 weeks old were divided to two groups. The first group was infected with 107.5 EID50 titer of the virus intranasaly and the second group was treated with saline normal. Following 72 hrs, renal tissues were collected and fixed in 10% formalin solution. The prepared microscopic sections with the thickness of 5-6 micron were stained using TUNEL method. In comparison to the control group, there were significant mean difference of apoptotic cells in renal tubular cells of the infected group (p<0.005). We demonstrated that A/chicken/Iran/772/2000 (H9N2) is able to induce apoptosis in renal tubular cells.
Serological Survey of the Reticuloendotheliosis Virus Infection in China Native Chicken Flocks  [PDF]
Peng Zhao*, Cheng-Tai Ma, Yan Du, Zhuan-Chang Wu and Zhi-Zhong Cui
Pakistan Veterinary Journal , 2012,
Abstract: To investigate the reticuloendotheliosis virus (REV) infection status in China, 2531 sera samples from 26 farms of native chickens were collected and tested for antibodies against reticuloendotheliosis virus. Serum samples analysis revealed 32.16% samples positive for REV-antibody. All 26 kinds of China native chicken strains have REV infection. REV-antibody positive rates of different flocks ranged from 1.01 to 67.68%. This study suggests that REV infection is very common in China native chickens flocks and more emphasis be given on its prevention.
Effects of Vaccination with Lentogenic Vaccine and Challenge with Virulent Newcastle Disease Virus (NDV) on Egg Production in Commercial and SPF Chickens  [PDF]
D.G. Bwala,F.O. Fasina,A. Van Wyk,N.M. Duncan
International Journal of Poultry Science , 2011,
Abstract: Since 2002, control of Newcastle Disease (ND) in South Africa has become complicated following the introduction of lineage 5d/VIId Newcastle Disease Virus (NDV) strain (locally known as goose paramyxovirus - GPMV). Commercially available ND vaccines appeared less effective. In this study, commercial and SPF hens in lay were vaccinated with La Sota vaccine and challenged with GPMV isolate to assess the effect of both vaccination and challenge on egg production. This study also compared the efficacy of cloacal and ocular routes of vaccination against challenge, following reports that cloacal vaccination offered a better protection against egg production losses than the oro-nasal route of vaccination. Vaccinated birds were fully protected (100%) against challenge by La Sota vaccine, but not against infection and replication of the virus, as birds showed varying degrees of macropathology and confirms the ability of virulent ND strains to infect and replicate even in vaccinated birds. Results also showed no clear difference in the protection of the birds against challenge with GPMV by either the cloacal and ocular routes of vaccination. Mmarginal to severe egg production drop was observed in both commercial and SPF birds after vaccination and challenge experiments.
Yeast-Derived Avian Influenza Virus Hemagglutinin Protein Induced Immune Response in SPF Chicken
Hongzhuan Wu,Karyn Scissum-Gunn,Narendra K. Singh,Shan-Chia Ou,Joseph J. Giambrone
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2011.999.1002
Abstract: Influenza pandemic virus appears to have originated from reassortment of inherited genes (HA, NA and PB1) from the avian influenza pool and genes from the human influenza virus. Specifically, regarding the low pathogenic Avian Influenza Virus (AIV), there is no commercial vaccine yet available. Hence, it is a priority to develop alow pathogenic avian influenza vaccine to help reduce morbidity and mortality outcomes during the next pandemic flu outbreak. In this study, the HA gene of an AIV A/Northern shoreler/AL/26/2006 isolate, AIV subtype H10N7 was expressed in the yeast Saccharomyces pombe and the recombinant protein was used to immunize Specific Pathogen Free (SPF) leghorn chickens held in Horsfall isolation units via the upper respiratory route at 1, 7 and 14 days of age. Serum and spleens of immunized chickens were analyzed and the results demonstrate that the yeast-derived recombinant HA protein is as effective as inactivated vaccine in inducing Hemagglutination Inhibition (HI) antibody, neutralization antibody and a Th1 like cytokine immune response. The results suggest that the recombinant HA protein could be a promising new subunit vaccine agent against low pathogenic AIV in chicken.
Analysis of the Effect of Virulent Marek s Disease Virus SORF2 Gene on its Horizontal Transmission Capacity Using Real-Time PCR
Shuai Su,Ning Cui,Yixin Wang,Aijun Sun,Pengfei Qi,Zimeng Chen,Peng Zhao,Zhizhong Cui
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2012.4648.4654
Abstract: Marek s Disease Virus (MDV) Chinese strain GX0101 was the first reported recombinant MDV field strain with one Reticuloendotheliosis Virus (REV) Long Terminal Repeat (LTR) insert. REV LTR in the GX0101 genome increased the potential for horizontal transmission. REV LTR fragment has the biggest impact on SORF2 gene. Researchers detected the influence of SORF2 gene deletion on its horizontal transmission ability by real time PCR. The result shows that GX0101ΔSorf2 possesses similar replication ability with bac-GX0101 no mater on the level of lymphocyte or feather follicle. Although, researchers can detect MDV positive in feather follicles of sentinel in contact chickens at age 10 in both groups respectively, the number of SPF chickens infected with bac-GX0101 by contact is higher than the number of GX0101ΔSorf2 infection group. Therefore, SORF2 gene has certain effect on the horizontal transmission ability of the virus.
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