A live-virus embryo-propagated canary pox vaccine was developed that can be safely and effectively applied by a single needle wing-web stab. Reactions to vaccination with passages lower than the 72nd passage were sometimes excessive in proliferative response. The 72nd and 100th embryo passages produced a more restricted lesion at the site of inoculation.
View Article and Find Full Text PDFFour tests of an inactivated emulsified vaccine against a herpesvirus infection (Pacheco's disease) in bodgerigars demonstrated that an effective vaccine could be produced with concentrated virus. Virus was propagated in chicken kidney cells, and cells and fluid were harvested 3 to 5 days after inoculation and sonicated. The virus was concentrated 100 x by centrifugation to produce a multiple emulsion vaccine that was protective against IM challenge exposure with live virus.
View Article and Find Full Text PDFThe response of mibolerone-treated chickens to infectious bursal disease virus (IBDV) was studied. Chickens fed a ration containing mibolerone at 1.5 parts per million (ppm) developed bursal atrophy by 4 weeks of age.
View Article and Find Full Text PDFModified infectious bursal disease virus (IBDV) administered ocularly to either susceptible or passively immune chicks did not induce protection against bursal atrophy by wild IBDV, while intramuscular (IM) or intrabursal (IB) injection protected susceptible chickens. No protection was obtained in passively immune chickens vaccinated IM or IB. Susceptible and passively immune chickens vaccinated with a single dose of killed-virus suspension (KVS) did not become resistant to wild IBDV challenge.
View Article and Find Full Text PDFIsolates of paramyxo-, herpes-, and orbiviruses from psittacine birds were characterized in the course of studies in cell cultures. The LBD-1 isolate, from a lovebird, was grown in chick kidney (CK) cells. It had the properties of a paramyxovirus but was found tobe serologically distinct from known avian paramyxoviruses.
View Article and Find Full Text PDFAvian Dis
November 1979
Eight viruses were isolated in embryonating eggs, from psittacine birds comprising a cockatiel, a budgerigar, 3 parrots, a love bird, and 2 rosellas. Initial attempts at isolation used 3 routes of embryo inoculation: yolk sac, allantoic sac, and chorioallantoic membrane (CAM). The most sensitive route was determined for 6 of the isolates by making comparative titrations by yolk sac, allantoic sac, and CAM routes of inoculation.
View Article and Find Full Text PDFAttempts failed to infect Coturnix quail with infectious bursal disease (IBD) virus by exposure at 7, 14, 21, and 31 days old. There were no clinical signs or gross and microscopic changes in the bursa of Fabricius, and serologic tests and virus isolation attempts from cloacal swabs were negative. Turkeys of two breeds exposed to IBD virus at 6 or 8 weeks old showed no clinical signs or lesions in the bursa of Fabricius, and the virus could not be isolated from cloacal swabs.
View Article and Find Full Text PDFThe virus-neutralization (VN) test was found much more sensitive than the agar-gel precipitin (AGP) test for detecting prior exposure to infectious bursal disease (IBD). Many sera that were negative in the AGP test were found to have VN antibodies, and virtually all sera in a commercial flock were free of precipitin but had VN titers. VN titers varied widely on a flock basis, and revaccination of an 8-month-old flock through the drinking water did not alter the antibody titers.
View Article and Find Full Text PDFDifferences in antibody response to three Newcastle disease virus (NDV) strains--B-1, LaSota, and Ulster--were investigated using the hemagglutination-inhibition (HI) micro-titer test in chickens hatched from ND-immune and unimmune flocks. When used singly as primary vaccines, the Ulster strain stimulated the lowest antibody response of the three in both immune and unimmune (susceptible) chickens. Subgroups of each of the primary-vaccinated groups were revaccinated with each of the three strains.
View Article and Find Full Text PDFTen of 16 isolates of avian adenovirus could be readily classified as members of serotypes 2, 5, or 7. However, 6 exhibited broad neutralization reactions which created typing problems. Detailed studies of these interactions revealed that our prototype for serotype 5 (i.
View Article and Find Full Text PDFA study of the pathogenesis of infectious laryngotracheitis (ILT) by the fluorescent-antibody (FA) technique in birds inoculated ocularly, intratracheally, by vent brush, and by aerosol revealed that the epithelium of the conjunctiva and respiratory tract are the tissues actively infected by natural routes of infection. The virus propagated at the sites of initial exposure but there was no evidence of spread by viremia. Viral antigen was detected 2-7 days postexposure and rarely thereafter.
View Article and Find Full Text PDFThe antigenic relationships of 12 strains of infectious bronchitis virus (IBV) were evaluated by a virus-neutralization procedure similar to that used in typing human rhinoviruses. Such a procedure consists of reciprocal neutralization tests performed by reacting 32-320 EID50 or plaque-forming units of virus with 20 antibody units of antiserum. Eight serologic groups were identified by chicken embryo assay, and 4 by plaque-reduction (90%).
View Article and Find Full Text PDFA comparison of 17 infectious bronchitis virus strains, using the same test procedure and assay system, demonstrated that stability at an acid pH is a variable characteristic of the avian coronaviruses.
View Article and Find Full Text PDFThe Clark 333 strain of infectious bronchitis virus (IBV) was substantially resistant to primary chicken cell-culture adaptation. More than 40 serial embryo passages were required before the virus would produce cytopathic alterations upon cell-culture inoculation. The cytopathic effect was characteristic of the effect of reported for IBV.
View Article and Find Full Text PDFA virus neutralization screening test using a 1:5 serum dilution of known antisera against approximately 100 embryo infective doses50 of an unknown virus was used to classify field isolates of infectious bronchitis virus. Such a test will detect the major antigen and antibody relationships. The Weakness of a screening test is that it does not quantitatively measure the minor antigen-antibody relationships between strains which would be essential to develop a classification scheme for infectious bronchitis isolates.
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