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Trials for isolation of reticuloendotheliosis virus from commercial chicken flocks for using the isolates in the detection of extraneous virus contamination in live vaccines
2011
Badawi A. A. | Salama S. S. | Elham A. Elibiary
In an attempt to isolate reticuloendotheliosis virus (REV) from field cases, plasma ofcommercial broiler chickens-suspect to have virus infection-were examined. Samples were inoculated in chicken embryo fibroblasts and after proper incubation infected cultures were assayed for REV-antigen by ELISA, immuno-peroxidase (IP) plaque assay, and PCR.Specificity of ELISA and IP was evaluated by comparing their results with that obtained by PCR. REV could be isolated and virus antigen was detected in cell cultures by all three techniques. Results showed that PCR and ELISA are more specific than IP in detection of REV-antigen. However, the sensitivity of ELISA was affected by the criterion used for determination of the cut-off point. Further studies are needed for full characterization of the isolated virus by using reference antiserum or strain specific primers for PCR.
Mostrar más [+] Menos [-]Antiviral activity of Curcuma longa against Newcastle disease virus (in vitro and in vivo studies)
2010
S. M. Tamam | H. M. Madbouly | Fadwa Amin
The antiviral activity of Curcuma longa against NDV on vero cell culture and in infected chicken was observed. The obtained results showed that low concentration of Curcuma longa 0.25% did not produce cytotoxicity on the vero cell. The effect of Curcuma longa on NDV titre was studied and the results revealed clearly that chickens treated with 1% Curcuma longa as Prophylactic also showed higher protection rate (90%), the chickens that treated with 0.5 % Curcuma longa showed protection rate (80%).Chicks that infected with NDV without treatment with Curcuma longa showed lower protection rate (8%). The chickens infected then treated with 1% Curcuma longa showed protection (65%) and the chickens infected then treated with 0.5% Curcuma longa showed protection (40%).
Mostrar más [+] Menos [-]Isolation of Lumpy skin disease virus form naturally infected cattle previously vaccinated with live attenuated sheep poxvirus vaccine
2007
S. M. Tamam
Lumpy skin disease virus (LSDV) was isolated, from naturally infected cattle that have a history of previous vaccination with live attenuated sheep pox virus (SPV) vaccine. The virus was isolated on chorio-allantoic membrane (CAM) of specific pathogen free (SPF) embryonated chicken eggs (ECE) and identified by agar gel precipitation test (AGPT) and neutralization test using specific hyperimmune serum against LSDV and SPV. Characteristic intracytoplasmic inclusion bodies was detected in trypsenized cell of infected CAM stained with H&E. Laboratory studies for characterization of isolated LSDV revealed that it was stable at a wide range of pH, but it was inactivated by exposure to 56 0C for 15 minutes. Treatment of isolated LSDV with lipid solvents (20% ethyle ether and chloroform) reduced the virus titer 3.2 and 4.4 log respectively after 24 hrs at 4 0C .On cross neutralization testcomplete neutralization of isolated LSDV was obtained with both reference LSDV and SPV antisera. Cattle vaccinated with live attenuated SPV vaccine under experimental condition found to be protected against natural field infection with LSDV.
Mostrar más [+] Menos [-]Characterization of Variant Strain of Newcastle Disease Virus in Egypt
2007
A. S. Abdel-Moneim | Azza A. El-Sawah | M. A. Kandil
During 2005, velogenic Newcastle disease virus (NDV) caused a major outbreak among commercial broiler chicken in Egypt. The outbreak raised concerns regarding the protective immunity of commercially available vaccines for prevention and control of this virus in poultry. The virus was isolated from broiler farm suffered from more than 95% mortalities. The isolate was confirmed not to be avian influenza virus (AIV) by rapid chromatographic strip test, and characterized as NDV using reverse transcription-polymerase chain reaction (RT-PCR) which amplified a portion of the fusion gene of NDV and haemagglutination inhibition (HI) test. This isolate confirmed to be velogenic viscerotropic NDV by mean death time (MDT) test and pathogenicity to 7-week old chickens. We tried to determine whether the existing commercial live NDV La Sota vaccine could provide protection against the isolated virus or not. Birds received a single dose of live La Sota type vaccine at 3 weeks of age and were challenged 2 weeks postvaccination with a lethal dose of NDV. Results indicated that the live vaccine did not protect against morbidity but reduced mortality in comparison to controls. All unvaccinated control chickens challenged with NDV died within 5 days post-challenge (pc). Protection from disease did not correlate with the presence of antibody titers (determined by HI) at day of challenge. These results underscore the need to develop new NDV vaccines and vaccine strategies for use during outbreak situations to protect birds from both disease and infection and to reduce virus shedding.
Mostrar más [+] Menos [-]Outbreaks of pneumonia in beef calves associated with bovine viral diarrhea virus seroconversion and other respiratory pathogens
2005
A. M. Khadr
The present study describes the clinical, serological and bacteriolological findingsin calves from two beef herds experiencing outbreaks of pneumonia. The clinical signs were nasal discharge, cough, pyrexia and increased respiratory rates. The morbidity and mortality rates over a month period were 40.72% and 15.63% respectively. Laboratory investigations revealed that bovine viral diarrhea virus (BVDV) was involved in and probably initiated both outbreaks as indicated by a significant increase in antibody titers against BVDV in sera of convalescent calves (paired serum samples). No antibodies bovine herpesvirus-1 (BHV-1), bovine respiratory syncytial virus (BRSV) and parainfluenza-3 (BPIV-3) viruses were detected in both acute and convalescent sera. Mycoplasma bovis was concurrently demonstrated in lungs of affected calves as it was isolated from 13 (81.25%) of examined lungs suggesting that there may be a synergism between bovine viral diarrhea virus and Mycoplasma bovis in the pathogenesis of pneumonia. A total of 15 (68.18%) isolates of Mannheimia haemolytica, 5 (22.73%) Pasteurella multocida, 1 (4.54%) Pseudomonase aerugenosa, 3 (13.64%) Staphylococcus aureus, 3 (13.64%) Actinomycis pyogenes, 1 (4.54%) Klebsiella pneumonae, 1 (4.54%) Streptococcus pneumonae, 2 (9.09%) E. coli and 2 (9.09%) Aspergellus fumigatus were recovered from lungs of calves suffering from pneumonia.
Mostrar más [+] Menos [-]Study on a New Isolate of Rabbit Haemorrhagic Disease Virus
2005
A. Y. Metwally | H. M Madbouly
Fifteen outbreaks with clinical picture and post- mortem lesions similar to that of rabbit haemorrhagic viral disease (RHVD) were investigated in vaccinated flocks during the period between February and July 2005 at Kafr El-Sheikh Governorate. Twelve representative liver homogenate were positive in haemagglutination test (HA) using human type (O) washed RBCs, with titer more than 1/160. Detection of virus particles by electron microscopy, histopathological findings as well as pathogenicity test , confirmed that the outbreaks were RHVD. The possible role of field rats for the transmission and spread of RHVD among rabbitaries was studied. Cross reactivity and cross protection tests were conducted. These tests proved that the newly emerged RHVD isolates were not closely related to classical local vaccinal strain of RHVD and may be a variant strain.
Mostrar más [+] Menos [-]Detection of bovine herpesvirus type 1 and bovine ephemeral fever virus antigens in cattle lymph nodes using three immunological assays
2005
S. M. Tamam | A. S. Abdel-Moneim
Lymph nodes (Ln) are the preferred samples for virus isolation and detection. Inthe present study, carcass and visceral Ln of apparently healthy cattle were screened for the presence of bovine herpes virus type 1 (BHV-1) and bovine ephemeral fever virus (BEFV) antigens. A total of 198 Ln (114 carcasses Ln and 84 visceral Ln) were collected. Lymph node homogenates were assayed by agar gel precipitation test (AGPT), rapid Staphyloccocal protein A (SPA) agglutination test and Dot-ELISA. The overall results revealed that BHV-1 antigens were detected in 43.9%, 56.1% and in 68.4% of carcass Ln, and in 29.8%, 47.6% and 57.1% of visceral Ln collected from slaughtered cattle by AGPT, SPA agglutination test and Dot-ELISA respectively. On the other hand, BEFV antigens were detected in 5.3%, 38.6% and 52.6% of carcass Ln, and in 6%, 41.7% and 54.8 % of visceral Ln collected from slaughtered animals by AGPT, rapid SPA agglutination test and Dot-ELISA respectively. The results showed high percentage of positive samples with SPA agglutination test and Dot- ELISA in comparison to AGPT for both BHV-1 and BEF.
Mostrar más [+] Menos [-]Studies on susceptibility of native and white Lohmann layer chickens breeds to infectious bursal disease virus isolate FY.97
2018
M. F. El-Kady | A. M. Dahshan | M. M. Ghanem | H. M. Madbouly
This study was done to evaluate susceptibility, protective titer level of maternal derived antibodies(MDAbs) of different chicken breed against virulent Infectious bursal disease virus (IBDV) local isolate Fy97 and prediction the optimal time for vacction. All breeds were experimentally infected orally with IBDV isolate Fy97 every 5 days following detection of MDAbs by ELISA. Clinical signs, mortality, lesions and Bursal Histopathology and lesion score were taken as criteria for comparison. Morbidity rates were observed as ≥ 30% in Fayoumi and Dandrawi infected at 15 days of age and in Senawi and Baladi and Lohmann at 20 days of age All breeds showed clinical sings of infection at 30-35 days of age where Senawi breed showed the highest values (65and 70%) followed by Fayoumi (55 and 55%), Dandrawi (50%), Baladi (55-45%) and Lohmann (50-45%). Mortality rates due to IBD infection varied from 0 to 35% in respective to age, in Fayoumi and Lohmann breeds where maximum 35 and 40% occurred at 30 day of age; respectively .Mortality in Dandrawi and Senawi varied from 5 to 40% and pass in close manner at all intervals with the highest value at 30 days of age while Baladi chicks showed same values but lower only at 20 and 25 days. Mean lesion scores in Fayoumi were the lowest at all intervals followed by Lohmann, Senawi, Baladi and Dandrawi. Results of ELISA titers at time of infection showed that Senawi chicks having the highest titers followed by Lohmann, Baladi, Dandrawi and Fayoumi at most intervals. So it necessitates more clarification of the causes of these phenomena and the role of genetics in protection against IBDV infection.
Mostrar más [+] Menos [-]Preparation of a trivalent oil-emulsion vaccine of inactivated Newcastle disease virus, infectious bronchitis virus and Haemophilus paragallinarum
2018
M. A. Abd El-Khalick | O. E. Kamal
Monvalent inactivated oil-emulsion, Newcastle disease virus (NDV), infectious bronchitis virus (IBV) and Haemophilus paragallinarum vaccines as well as a trivalent one (NDV + IBV + HP) were prepared. The cellular and humoral immune responses of chicken to these vaccines were evaluated by using lymphocytes blastogenesis assay, haemagglutination-inhibition, serum neutralization, tube agglutination and challenge tests. The results showed that the trivalent vaccine was safe, efficient as monovalent vaccines and protected chicken against Newcastle, Infectious bronchitis and infectious coryza
Mostrar más [+] Menos [-]Infectious diseases in aquarium ornamental pet fish
2019
Pedro Henrique Magalhães Cardoso | Andrea Micke Moreno | Luisa Zanolli Moreno | Carolina Helena de Oliveira | Francisco de Assis Baroni | Samara Rita de Lucca Maganha | Ricardo Luis Moro de Souza | Simone de Carvalho Balian
Aquarium ornamental pet fish constitute a major segment in the pet industry, with the United States, Europe, and Japan dominating the market. There are approximately 1,500 marine fish species and over 4,500 freshwater fish species commercialized as aquarium ornamental pet fish. Fish are the fourth most common pet present in Brazilian homes. In Brazil, aquarium ornamental pet fish can be marketed and distributed from different parts of the Brazilian territory and the world. Commercialization and circulation of living animals without the use of adequate prophylactic management procedures enables dissemination of a number of agents responsible for infectious diseases. Aquarium pet fish can also carry pathogenic agents, of bacterial, viral, fungal, or parasitic etiology, that may have a zoonotic feature endangering the persons handling the animals. This review presents the main pathogenic infectious agents of bacterial, viral, andfungal etiology that affect aquarium pet fish, as well as the prevention and control measures to ensure sanitary excellence in this segment.
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