in vitro cultivation of cells from the chorioallantoic membrane of chick treatment of chorioallantoic membranes from embryonated eggs with collagenase and hyaluronidase before the conventional application of trypsin cells could be grown in culture which supported growth of a large variety of myxoviruses, herpesviruses, avian reoviruses and the infectious bronchitis virus of chickens. the cultures could be used for sensitive plaque assays and neutralization tests.1975165393
use of the indirect fluorescent antibody method for detecting antibodies to infectious bronchitis virus in chickens serum. 1975167061
two new isolants of infectious bronchitis virus with polyvalent immunogenicity.the immunizing capacity of two new field isolants of avian infectious bronchitis virus (ibv) was tested in vivo. chickens vaccinated with either isolant resisted challenge with 6 serotypes of ibv, including some of the types most commonly isolated from chickens. the two new isolants, identified herein as california "g" and california "s," appear to be immunologically different from each other and from the other 6 types tested. the polyvalent immunogenicity of both g and s is noteworthy, and pote ...1975168851
identification of infectious bronchitis virus by interference with the b-1 isolant of newcastle disease virus. waxing and waning of interference.the massachusetts and the connecticut types of infectious bronchitis virus (ibv) were identified by interference in embryonating chicken eggs (ece) with the production of hemagglutinin by the b-1 isolant of newcastle disease virus (ndv). this interference test appears to be specific because the above interference was eliminated by adding type-specific anti-ibv serum to the ibv-ndv system; however, interference was not detectable when fowlpox virus (fpv) and infectious laryngotracheitis virus (lt ...1975168852
the isolation and some biological properties of a variant avian infectious bronchitis virus.a virus isolated from a respiratory disease in chickens was identified as infectious bronchitis virus (ibv). by serum neutralisation tests the virus was shown to be serologically distinct from the massachusetts type but to possess a one-way relationship with the connecticut type. experimentally, it caused a relatively mild respiratory disease in baby chicks. vaccination of young chicks with h-120 massachusetts ibv vaccine afforded a high degree of protection against challenge with the isolate. s ...1976179183
local immunity in newcastle disease: some recent experiments.following primary exposure by the ocular route to lentogenic newcastle disease virus (ndv) the lacrymal fluid, saliva and tracheal washes of three-week old specific pathogen free chickens acquired specific virus-neutralizing activity which considerably exceeded transudation of circulating antibody. all three secretions contain iga which, at least in saliva, accounted for 85% of its activity, the remanider being due to igg. antibody in secretions limited, but did not prevent, reinfection of the ...1976182586
the proposed international standard for infectious bronchitis vaccine (live).an h-120 strain of infectious bronchitis virus was prepared in a form suitable to serve as an international standard for infectious bronchitis vaccine (live). accelerated degradation studies carried out on this vaccine showed it to be of suitable stability to serve as a standard. results from a collaborative assay involving ten laboratories demonstrated that the proposed standard reduced the variation in virus titrations both within and between laboratories. this assay also showed that firstly ...1976182587
comparative tests on safety and potency of iba vaccines.during a comparative test on the pathogenicity and immunogenicity of a non-adapted and an embryo-adapted ida virus, following observations were made: 1) the non-adapted virus remained pathogenic as determined by weight loss and bursal lesions. clinical signs and mortality did not occur. a change in the virulence did not occur during back passages; 2) the immunosuppressive effect of the non-adapted virus was diminished by maternal antibodies; 3) the embryo-adapted virus produced little pathogenic ...1976182590
isolation of infectious bronchitis virus from broiler chickens in infectious-bronchitis-like virus was isolated from 6-week-old broiler chickens unvaccinated with infectious bronchitis virus (ibv). the isolate produced lesions in embryonating chicken eggs (ece) and clinical signs in birds characteristic of ibv. serum-neutralization and agar-gel diffusion tests demonstrated the serological relationship of this isolate to ibv.1976183652
morphogenesis of avian infectious bronchitis virus in primary chick kidney cells.primary chick kidney cells were infected with avian infectious bronchitis virus (ibv) and examined by electron microscopy. virus particles entered the cells by viropexis and distinction could be made between engulfment by cell processes (phagocytosis) and entry by micropinocytosis in coated transport vesicles. virus maturation occurred by budding into either the cisternae of the endoplasmic reticulum or cytoplasmic vacuoles, and evidence was obtained to suggest that the viral surface projections ...1976187144
electron microscope observations on the entry of avian infectious bronchitis virus into susceptible cells.infectious bronchitis virus was observed to enter cells of chicken chorioallantoic membrane by viropexis. there was no support for the suggestion that entry took place by fusion of viral and plasma membranes. the results of electron microscopy showed that virus attachment occurred both at 4 degrees and at 37 degrees c. viropexis was not observed until the preparations were warmed. similar results were obtained using chicken kidney cells. quantitative data obtained from a plaque counting system e ...1976187152
effect of infectious bursal disease on the response of chickens to mycoplasma synoviae, newcastle disease virus, and infectious bronchitis 35 days of age, chickens which as 1-day-old chicks were inoculated with the infectious bursal disease virus (ibdv) had significantly lower antibody titers against mycoplasma synoviae, newcastle disease virus, and infectious bronchitis virus than did those never inoculated with ibdv. the ibdv also had a marked effect on the development of air-sac lesions. birds infected with ibdv that were later inoculated with m synoviae (day 14), newcastle disease virus (days 14 and 28) experienced an increa ...1977190926
typing field isolates of infectious bronchitis by the plaque-reduction test.a technique is described for typing field isolates of infectious bronchitis virus by plaque-reduction assay of the serum antibody response of chickens experimentally infected with such isolates. also reported are use of the technique with field isolates and a comparison of results obtained in plaque-reduction assay and in tracheal-ring organ-culture assay.1978206255
response to several avian respiratory viruses as affected by infectious bursal disease virus.after being inoculated with the infectious bursal disease virus (ibdv) at one day of age, specific-pathogen-free chickens were inoculated with either newcastle disease virus (ndv), infectious bronchitis virus (ibv), or infectious laryngotracheitis virus (iltv). their immunity was challenged 2-3 weeks later with homologous virus, and antibody titers were determined for iltv and ibv. several studies were made to determine the effects of ibdv on the development of persistent or chronic virus infect ...1978206256
vaccination immunity to selected diseases in chickens fed the androgen analog mibolerone.chickens fed the androgen analog mibolerone during the first 7 weeks of life regress their bursa of fabricius but can be properly immunized by vaccination against avian pathogens of major economic importance such as newcastle disease virus, infectious laryngotracheitis virus, avian encephalomyelitis virus, infectious bronchitis virus, fowl pox virus, marek's disease virus, and pasteurella multocida, the pathogen causing fowl cholera. these findings on immunocompetence to infectious agents are im ...1978209430
vaccination against infectious bronchitis and the immunosuppressive effects of infectious bursal immunosuppressive effect was demonstrated in chickens which were infected with infectious bursal disease virus (ibdv) early in life and prior to or shortly after vaccination with infectious bronchitis virus (ibv). this effect was evident by an increased susceptibility to respiratory tract infection with ibv and reduced virus-serum neutralizing antibody levels. chickens which were hatched from dams susceptible to infectious bursal disease (ibd) were less responsive to ibv immunization attempts ...1978209433
[measures against infectious bronchitis in chickens]. 1978211704
studies on avian infectious bronchitis virus in new zealand. i. serotypes. 1977208028
a long-term study of the pathogenesis of infection of fowls with three strains of avian infectious bronchitis virus. 1978206936
[the influence of temperature and incubation time on the propagation rate of the chicken infectious bronchitis virus in egg culture]. 1978205206
isolation of avian infectious bronchitis virus from experimentally infected chickens.virus was recovered from the faeces of chickens infected at three or four weeks of age for more than 20 weeks after infection with commercial vaccines or with the t strain of avian infectious bronchitis virus (ibv). virus was not recovered from the trachea, liver, spleen, bursa or kidneys of t strain infected birds longer than 29 days after infection at which point ibv was recovered from the bursa of a single infected bird. in a subsequent experiment ibv was recovered from the caecal lymph nodes ...1977203987
comparative ultrastructural studies on endemic (balkan) nephropathy and chicken embryo nephritis caused by infectious bronchitis virus. ii. chick embryo nephritis. 1977196486
comparative ultrastructural studies on endemic (balkan) nephropathy and chicken embryo nephritis caused by infectious bronchitis virus. i. endemic (balkan) nephropathy. 1977196485
airsacculitis induced in broilers with a combination of mycoplasma gallinarum and respiratory viruses.mycoplasma gallinarum was isolated from tracheas and air-sac lesions from broilers in flocks having higher than normal condemnations due to airsacculitis. a representative m. gallinarum isolant, given by aerosol or by air-sac inoculation, produced air-sac lesions in young chickens when given in combination with a vaccine combining newcastle disease and infectious bronchitis or with a field strain of infectious bronchitis virus.1978219834
[infectious bronchitis and pullorum disease in chickens]. 1979222043
influence of environment on airsacculitis: effects of relative humidity and air temperature on broilers infected with mycoplasma synoviae and infectious bronchitis.mycoplasma synoviae (ms) obtained from broiler chickens condemned for airsacculitis was used to determine the influence of air temperature and relative humidity on the severity of airsacculitis produced experimentally. infectious bronchitis virus was administered to 3-week-old broilers 5 days before aerosol exposure to ms broth cultures, producing extensive airsacculitis within 21-day study periods. high (31-32 c), medium (19-24 c), and low (7-10 c) air temperatures were studied in conjection wi ...1977194567
growth kinetics of embryo- and organ-culture adapted beaudette strain of infectious bronchitis virus in embryonated chicken eggs.three beaudette strains of infectious bronchitis virus (ibv) [two chicken-embryo trachea-culture-adapted (e71cet10 and e71cek10cet30) and one embryo-adapted (e72)] were propagated in 10-day-old embryonated chicken eggs (ce) to investigate growth and lethality patterns. the e72 and e71cek10cet30 viruses were similar in growth pattern as to logarithmic phase and maximum virus production, but 95% of the ce mortality with e72 virus occurred between 20 and 32 hours whereas with e71cek10cet30 60% mort ...1979226050
organ culture studies on the efficiency of infection of chicken tissues with avian infectious bronchitis virus.long-term organ cultures of a range of tissues collected from specific pathogen-free chickens were employed to determine their susceptibility, and their capacity for subsequent virus production, following inoculation with avian infectious bronchitis (aib) virus. when inoculated with approximately 2-0 log10 median ciliostatic doses (cd50) of a classical highly egg-adapted vaccine strain (h120) of aib virus, 9 of 23 tissues were shown to be susceptible, namely the nasal turbinates, trachea, air sa ...1976183805
[the influence of infectious bronchitis virus on egg production, fertility, hatchability and mortality rate in chickens (author's transl)].in 35 flocks comprising almost 100,000 white plymouth rock birds producing hatching eggs, infectious bronchitis (ib) caused a decline in production which appeared to be connected with the age of the birds, when the outbreak started (table i). in outbreaks of ib in pullets 3-4 weeks before they are ready to lay there is a considerable risk of delay of production and a generally too low yield (fig 1). egg laying birds, 25-34 weeks of age, suffered a drop in production from 20-80% (on an average 40 ...1976183182
variant infectious bronchitis virus isolated from indiana chickens.infectious bronchitis virus (ibv) associated with a catarrhal tracheitis, sudden decline in egg production, and reduced shell quality was isolated from an indiana white leghorn breeder flock. it was found to be serologically different from massachusetts, connecticut, iowa 97, iowa 609, florida, arkansas 99, jmk, holte, gray and se 17 ibv serotypes. two different massachusetts vaccine strains protected chickens from respiratory signs but not against virus infection using the isolant for challenge ...1976181740
the isolation of lentogenic strains of newcastle disease virus in australia.twelve isolations of newcastle disease virus were made from 77 clinical samples from chickens from conjunctivitis, respiratory disease, proventriculitis and bursal atrophy. nine of the isolations were made from chickens with conjunctivitis. the viruses were identified as newcastle disease virus by inhibition of their haemagglutinins with specific antiserum to newcastle disease virus. the viruses failed to kill chicken embryos after inoculation into the allantoic cavity and they were judged to be ...1978687276
immunity to avian infectious bronchitis.avian infectious bronchitis is recognized clinically as a respiratory disease in its only natural host,the chicken, but the virus is disseminated throughout other systems by a viraemia with localization especially in the kidney and oviduct. the sensitivity or instability of the antigenic and immunogenic properties of the virus under laboratory stress or natural influences complicates the selection of seed virus for vaccines. modified or attenuated active virus vaccines induce greater protection ...1975805074
strains of infectious bronchitis virus on the delmarva peninsula and in arkansas.the constant-virus variable-serum neutralization test in chicken tracheal cultures was used to serotype infectious bronchitis virus (ibv) isolants from the delmarva peninsula and arkansas. of 106 isolants obtained from delmarva in 1971-1974, 93 were found to be the jmk strain, 5 massachusetts (mass), 5 connecticut (conn), 2 a new strain designated maryland (md) 27, and 1 a new strain designated md 31. of 26 isolants obtained from arkansas between october, 1971, and february, 1973, 17 were arkans ...1976180960
vaccination and revaccination with a holland (h) strain of infectious bronchitis chickens possessing maternally derived immunity to massachusetts-type infectious bronchitis virus (ibv) were vaccinated by the eyedrop route with a holland (h) ibv strain of the massachusetts type. vaccination was done with the 72nd and 92nd passages in chicken embryos. attenuation of the virus was done in the authors' laboratory. four weeks postvaccination the immunity was challenged with 8 different ibv serotypes. a broad spectrum of protection from respiratory signs was obtained i ...1976180959
vaccination of young chickens with live vaccine against some new zealand isolates of infectious bronchitis virus. 1975170569
single and mixed infections of avian infectious bronchitis virus and mycoplasma gallisepticum.comparative studies of the clinical signs, pathological changes, multiplication of the pathogens and serological responses were made of groups of chickens infected with either or both avian infectious bronchitis virus and mycoplasma gallisepticum. electron microscopic examination of thin sections of infected tracheas showed that the multiplication of m. gallisepticum was greatly enhanced in the tracheas of chickens which had been previously or simultaneously infected with avian infectious bronch ...19751126565
serotyping of avian infectious bronchitis viruses by the virus-neutralization test.the 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%). in general, serologic groupings were not distinct but re ...1975169804
morphological changes of chicken tracheas and tracheal organ cultures infected with avian infectious bronchitis virus studied in scanning electron microscope.chicken tracheas infected in vitro in organ culture and in vivo with avian infectious bronchitis virus (ibv) were studied by scanning electron microscopy. in in vitro infection in organ culture the columnar epithelial cells lining the tracheal ring lost their cilia and rounded up in 48 hr. there were numerous elevations and holes on the infected cell surface. subsequently the cells sloughed off. in in vivo infection the tracheal epithelial cells lost their cilia in 4 days. these cells without ci ...1975169800
induction of anti-viral immune responses by immunization with recombinant-dna encoded avian coronavirus nucleocapsid protein.immune responses to the infectious bronchitis virus (ibv) nucleocapsid protein were studied using a recombinant-dna expression product. in mice, a lymphocyte proliferative response and a delayed-type hypersensitivity reaction to ibv were induced upon immunization with this nucleocapsid protein. next, we studied the role of the expressed nucleocapsid protein in induction of a protective immune response to ibv in chickens. chickens were primed with nucleocapsid protein and subsequently boosted wit ...19921311490
relationship of common avian pathogen antibody titers in so-called chicken anemia agent (caa)-antibody-positive chicks to titers in caa-antibody-negative chicks.antibody titers for infectious bursal disease virus (ibdv), infectious bronchitis virus, newcastle disease virus, and reovirus from chicks with chicken anemia agent (caa) antibodies were compared with antibody titers from their caa-antibody-negative counterparts. these comparisons were made in 396 chickens that were 1 day, 2 weeks, 8-9 weeks, 10 weeks, 17 weeks, or 29-32 weeks old. only one serum sample was collected from any given chick or chicken. there were no significant differences between ...19921320864
serological responses of broiler-type chickens, with and without newcastle disease and infectious bronchitis vaccine, to experimental infection with mycoplasma synoviae by foot pad, air sac and aerosol.serum plate (sp) and tube agglutination (ta) reactions and geometric mean mycoplasma synoviae (ms.) hemagglutination-inhibition (hi) titers were determined on chickens infected at 21 days of age with ms. by foot pad, air sac and aerosol. one-half had been given newcastle disease (nd) and infectious bronchitis (ib) vaccine in the water at 20 days of age, and the other half had not been vaccinated with nd and ib vaccine. blood was taken at 3, 4, 6 and 8 weeks after ms. infection. geometric mean hi ...1975168564
some immunological aspects of a recent australian isolate of infectious bronchitis infectious bronchitis virus, designated g48, isolated from birds during an outbreak of nephritis in a previously vaccinated broiler flock, overcame the resistance induced in birds vaccinated with 2 commercially available vaccines. birds vaccinated with the a isolate of infectious bronchitis resisted challenge with this new virus. cross neutralisation studies revealed that the new virus was serologically distinct from the 4 viruses tested. homologous antiserum to g48 did not neutralise the oth ...197662570
avian infectious bronchitis vaccine: primordial or derived virus?vaccine formulations of virulent, modified/attenuated, or inactivated mono- or multivalent types of chicken embryo-propagated avian infectious bronchitis virus (ibv) at different passage levels and administered by non-parenteral routes have been used for immunization of chickens against the disease. two doses of vaccines are generally used: 1) high level virus of lessened virulence, antigenicity and immunogenicity as "derived" from its parental virus via serial passage in and selective adaptatio ...197660263
growth comparisons of avian infectious bronchitis virus strains in organ cultures of chicken tissues.six strains of avian infectious bronchitis virus (ibv) were used to inoculate explants of a range of 15 chicken tissues and virus growth kinetics observed over a period of 96 hours thereafter. similar patterns of virus production were given by all 6 strains from explants of any particular tissue such as the nasal turbinates, trachea, lung, air sacs and oviduct. nevertheless, significant differences in behaviour between strains were noted for different tissues and in the efficiency with which cer ...1978206229
escherichia coli multiplication and lesions in the respiratory tract of chickens inoculated with infectious bronchitis virus and/or e. coli.escherichia coli numbers and histopathological changes were studied in the respiratory tract of line 151 chickens intranasally inoculated with infectious bronchitis virus (ibv) and/or virulent e. coli; this line is highly susceptible to ibv. chickens inoculated with ibv alone showed increased numbers of e. coli in the trachea and had tracheitis, airsacculitis, and bronchiolitis. one of 17 chickens inoculated with ibv alone died with fibrinopurulent serositis. chickens inoculated with ibv and e. ...19921336661
[vaccination of chicks against infectious bronchitis and newcastle disease]. 1978216138
induction of chicken interferon by avian infectious bronchitis virus.the ability of nine strains of avian infectious bronchitis virus (ibv) to induce chicken interferon has been investigated using semliki forest virus for the tests. the beaudette, h120 and connecticut 46 strains induced interferon in the allantoic fluids of embryonated hens' eggs, the highest titre (1 : 30) being associated with beaudette; but these as well as the massachusetts m-41 and h52 strains failed to yield interferon in primary monolayer cultures of chick kidney cells as did all nine stra ...1978214833
effect of in ovo bursectomy on the course of an infectious bronchitis virus infection in line c white leghorn chickens.white leghorn line c chicks were surgically bursectomised (bx) in ovo to eliminate antibody production. after inoculation with infectious bronchitis virus (ibv) at 14 days after hatching, bx chicks experienced a more severe and longer lasting infection than intact chicks. the severity and duration of clinical infection in the bx chicks resembled that previously observed in the highly susceptible line 15i chicks, however no increase in mortality was observed, in contrast to the high levels of mor ...19911648896
viral pathogenesis of a nephrotropic infectious bronchitis virus isolated from commercial pullets.infectious bronchitis was diagnosed in 3-to-4-week-old pullets from an outbreak in a commercial flock in california. the disease was characterized by head swelling, watery discharge from the eyes and nostrils, and urates in kidneys. mortality ranged from 1.8% to 12.5% per week. the isolation of a coronavirus from a suspension of pooled kidneys from clinically ill chickens at the fifth passage in 10-day-old chicken embryos, gross and histologic renal lesions, and seroconversion by enzyme-linked i ...19911649594
a comparative evaluation of chicken embryo tracheal organ cultures for the assay of avian infectious bronchitis virus. 1978214447
igm responses in chicken serum to live and inactivated infectious bronchitis virus vaccines.intramuscular (i.m.) administration of infectious bronchitis virus (ibv) oil-emulsion vaccine (oev) to ibv-primed or unprimed chickens resulted in the production of zero or minimal concentrations of ibv-specific igm in the serum, as measured by enzyme-linked immunosorbent assay of gel chromatography fractions. live-attenuated infectious bronchitis (ib) vaccine given i.m. or by eyedrop stimulated the production of ibv-specific igm in similar amounts following inoculation by both routes. these lev ...19911659365
plastic multiwell plates to assay avian infectious bronchitis virus in organ cultures of chicken embryo trachea.simple assay systems for infectivity titrations of avian infectious bronchitis virus (ibv) in chicken embryo trachea organ cultures (oc) were developed using plastic multiplate wells with one tracheal ring per well; these assays appeared to be much more satisfactory than the conventional rolled-tube method. the medium, 0.05 m hepes (n-2-hydroxyethylpiperazine-n'-2-ethanesulfonic acid)-buffered eagle minimal essential medium was not changed during observation. a medium containing 0.4% bovine seru ...1978214456
comparison of duration of immunity in chickens infected with a live infectious bronchitis vaccine by three different routes.three groups of chicks were vaccinated by aerosol, intra-ocular and drinking water routes with a live infectious bronchitis (ib) vaccine. at one, two, six, 15 and 32 weeks after vaccination five birds from each group were sampled for testing for ib haemagglutination-inhibiting (hi) antibodies and challenged. assessment of susceptibility to infection was measured by recovery of virus from individual tracheas and from kidney and gonad pools four days after challenge. virus was isolated from all ki ...1979229532
studies on avian infectious bronchitis virus (ibv). iii. interferon induction by and sensitivity to interferon of ibv.the induction of interferon by avian infectious bronchitis virus (ibv) and the sensitivity of ibv to interferon were studied. the results of experiments with ten ibv strains are summarized as follows. 1. all the ibv strains tested induced interferon in chick embryo (ce) cells, chicken kidney (ck) cells and embryonated eggs. the iowa-609 strain induced about 1000 units of interferon in ce cells while the beaudette-42 strain induced about 200 units of interferon in embryonated eggs; the interferon ...1979228636
characterization of a new infectious bronchitis virus isolate. iii. cell-culture adaptation of clark 333.the 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. adaptation was not accomplished by alternating serial passages in embryo and cell-cultured systems. a careful monitoring of cell-culture fluid infectivity by e ...19751120038
the neutralizing characteristics of strains of infectious bronchitis virus as measured by the constant-virus variable-serum method in chicken tracheal cultures.the constant-virus variable-serum neutralization test in chicken tracheal organ cultures was employed in cross-neutralization tests with the following infectious bronchitis viruses: massachusetts 41, connecticut, iowa 97, iowa 609, holte, jmk, clark 333, se 17, florida, and arkansas 99. these viruses all proved serologically distinct by this method. chickens immunized with the connecticut strain and later challenged with arkansas 99 were not protected against it.19751120040
pathobiology of cryptosporidiosis (c. baileyi) in broiler chickens.pathologic and clinicopathologic changes were examined in broiler chickens inoculated with cryptosporidium baileyi (cb) alone or in combination with infectious bronchitis virus (ibv), infectious bursal disease virus (ibdv) or escherichia coli (ec). concurrent infections with cb and either ibv or ec resulted in a greater respiratory inflammatory response than either agent given alone. concurrent cb, ibv or ec infections resulted in a decreased density of respiratory cryptosporidial stages. no int ...19911667932
the resistance to reinfection of tracheal organ cultures from chickens previously infected with avian infections bronchitis virus.lower titres of avian infectious bronchitis (aib) virus were found following the infection of tracheal organ cultures prepared from chickens that had been given aib virus intranasally six weeks previously than were found following the infection of organ cultures prepared from untreated or from passively-immune chickens. no infectious virus was found in the tracheal organ cultures at the time they were prepared.1978212798
ph stability studies with avian infectious bronchitis virus (coronavirus) strains.a 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.1975234539
identification of two new polypeptides encoded by mrna5 of the coronavirus infectious bronchitis virus.the second smallest subgenomic messenger rna, mrna5, of the coronavirus infectious bronchitis virus includes in its "5' unique region" two separate open reading frames (5a and 5b), whose coding function has not so far been established, and thus it may represent a dicistronic messenger rna. we report here that two polypeptides with the sizes expected for the 5a and 5b products can be synthesised by in vitro translation of a single artificial mrna containing both the 5a and 5b orfs. to establish w ...19921309280
variant serotypes of infectious bronchitis virus isolated from commercial layer and broiler chickens.twenty infectious bronchitis virus (ibv) field isolates obtained from commercial layer and broiler chickens in 1987 and 1988 were serotyped using the virus-neutralization (vn) test. six different previously unrecognized variant serotypes were identified from a total of seven isolates from layer chickens. only two isolates, both from maine, were the same variant serotype. variant serotypes also were recovered from layer flocks in illinois and washington and the province of ontario, canada. two di ...19911851422
health survey of backyard poultry and other avian species located within one mile of commercial california meat-turkey flocks.a survey was conducted to characterize domestic and exotic bird populations, estimate seroprevalence to selected disease agents, and describe health management practices on 62 premises containing "backyard" flocks located within one mile of 22 commercial california meat-turkey flocks participating in national animal health monitoring system (nahms). chickens were present on 56 backyard premises and turkeys on seven. antibodies were identified against mycoplasma gallisepticum, m. synoviae, m. mel ...19911854324
epithelia-damaging virus infections affect vitamin a status in chickens.the effect of infection with infectious bronchitis virus (ibv) and reovirus (rv) on vitamin a status was investigated in chickens with a normal or marginal intake of vitamin a. at the age of 4 wk, chickens were infected with either ibv or rv, primarily affecting the respiratory or intestinal tract, respectively. both viruses lowered plasma retinol levels significantly. the effect was more pronounced in chickens fed a diet marginally deficient in vitamin a than in those fed a diet adequate in vit ...19921310111
products of the polymerase-encoding region of the coronavirus ibv. 19901966413
local immunity in the respiratory tract of the chicken. i. transudation of circulating antibody in normal and virus-infected birds.three-week-old chickens were given sheep erythrocytes or bovine serum albumin intravenously. seven days later their tears and saliva possessed low levels of antibody to those antigens. concurrent infection with lentogenic newcastle disease virus (ndv) caused a significant increase in transuded antibody in those fluids. in chickens with circulating antibody to ndv, induced by parenterally administered inactivated vaccine, respiratory infection with heterologous infectious bronchitis virus resulte ...19761027720
differentiation of avian infectious bronchitis virus isolates by thermal sensitivity.six isolates of avian infectious bronchitis virus (ibv) at different passage levels in the chicken embryo were tested for sensitivity at 56 c, with the following results: 1) isolates differed in thermal sensitivity; 2) virus was inactivated in a first-order exponential-kinetics 2-component fashion indicative of a heterogeneous population with a preponderance, 98% or more, of thermal-sensitive (s) virions over thermal-resistant (r) virons; 3) r virions 2-component populations were inactivated; 4) ...1978212002
safety of temperature sensitive mutant mycoplasma gallisepticum vaccine.a temperature sensitive (ts) vaccine strain designated ts-11 was selected after exposure of a low passage culture of the immunogenic australian field isolate (strain 80083) of mycoplasma gallisepticum to 100 mg/ml of n-methyl-n-nitro-n-nitrosoguanidine. viable counts (assayed as colour changing units (ccu)/25 microliters) of a thawed stock culture of ts-11 were typically log10 3 to log10 5 higher when incubated at 33 degrees c (the permissive temperature) than duplicate viable counts incubated a ...19902143067
immunity to infectious bronchitis virus from spray vaccination with derivatives of a holland was made of the protection of chickens from spray vaccination with different modifications of a holland (h) strain of infectious bronchitis virus (ibv). noted in each trial were the virus-serum-neutralizing antibody titers induced and the virulence of the vaccine virus at different passage levels. protection against respiratory signs was good from challenge with a homologous virus serotype as well as with 5 heterologous ibv isolates. this occurred from vaccinating day-old chicks possessing ...1976176991
cross-protection studies with a holland strain (noblis h-52) of infectious bronchitis virus. 1976176990
new strains of infectious bronchitis virus isolated in maine.twelve ibv isolants from diseased chickens in maine were studied by serum-neutralization tests in chicken tracheal culture. six isolants were neutralized by mass-type antisera. the serum-neutralizing characteristics of six other isolants from vaccine breaks differed from any of the standard ibv viruses and appear to comprise three new strains, maine 209, 212,and 246. the data provide additional evidence that strains of ibv responsible for disease probably vary from region to region and that the ...1976176989
identification of seven isolants of infectious bronchitis virus by interference with the b-1 isolant of newcastle disease isolants of infectious bronchitis virus (ibv) interfered with the development of hemagglutinins (ha) by the b-1 isolant of newcaslte disease virus (ndv) in eggs previously inoculated with these ibv isolants. the i50 [defined as the minimum amount of ibv needed to produce, upon inoculation in embryonating chicken eggs (ece), ha interference in 50% of these ece reioculated 10 hr later with 10(2,41 eid50 (ha) of the b-1 strain of ndv] was less than 1 eid50. the interference was considered spe ...1976176988
the use of chicken tracheal organ cultures for the isolation and assay of avian infectious bronchitis virus.a study has been made of the use of chicken tracheal organ cultures for the isolation and assay of avian infectious bronchitis (aib) virus from both naturally and experimentally infected chickens. six strains of aib virus were investigated, 3 of which had been isolated from natural outbreaks of disease. two of the virus isolations from the outbreaks of aib were made directly into tracheal organ cultures without passage in embryonated eggs. organ cultures prepared from 20-day-old embryos were use ...1976176965
the effect of mixed live vaccines of newcastle disease and infectious bronchitis on the chicken respiratory tract.the effect of mixed live vaccines of newcastle disease (nd) and infectious bronchitis (ib) on specific pathogen-free chickens aged 7 days was investigated. the chickens were inoculated intranasally with mixed live vaccines with and without escherichia coli, or with e. coli alone. "vaccine 1" consisted of nd virus strain b1 and ib virus strain on; "vaccine 2" consisted of nd virus strain b1 and ib virus strain h120. the tracheas of chickens inoculated with the vaccines and e. coli and with the va ...19921322945
comparison of different computational methods for measuring antibodies to avian infectious bronchitis virus in single serum dilution.twenty-eight one-day-old chickens with infectious bronchitis virus (ibv) maternal antibodies were immunized with strain h120 (bronchovac-i, phylaxia) in spray form. the chickens were kept in an isolator. on day 42 and 56 the chickens were immunized with ibv strain m41 (10(3.0)eid50/0.1 ml). serum antibody titres were measured by both serial dilution and single dilution elisa on day 42, 56 and 76. "twice negative average" (tna), "sample to positive" (sp) and "subtraction method" (sm) titres were ...19921339061
the effects of oestrogen and progesterone on re-excretion of infectious bronchitis virus strain g (correction of straing) in spf chickens.the effects of oestrogen and progesterone on the re-excretion of ib virus strain g in chickens infected at day-old was evaluated in this study. following infection of the chickens at day-old, the birds were swabbed regularly from the trachea and cloaca until no more virus was isolated from either site. between 10 and 14 weeks of age oestrogen and progesterone were administered by intramuscular injection to infected or control chickens. an infected but non-hormone injected group was maintained. a ...19911666637
infectious bronchitis virus detection in allantoic fluid using the polymerase chain reaction and a dna probe.a rapid extraction procedure was developed to purify infectious bronchitis virus (ibv) rna from the allantoic fluid of inoculated embryonating eggs. reverse transcription of viral rna and the polymerase chain reaction (pcr) were used to amplify the viral genome from eight different strains of ibv comprising five different serotypes. a biotinylated dna probe, prepared to a sequence within the pcr amplification product of the beaudette strain of ibv, was used in a dot-hybridization assay; it detec ...19921320869
neuraminidase treatment of avian infectious bronchitis coronavirus reveals a hemagglutinating activity that is dependent on sialic acid-containing receptors on erythrocytes.the interaction of infectious bronchitis virus (ibv) with erythrocytes was analyzed. the binding activity of ibv was not sufficient to agglutinate chicken erythrocytes. however, it acquired hemagglutinating activity after treatment with neuraminidase to remove alpha 2,3-linked n-acetylneuraminic acid from the surface of the virion. pretreatment of erythrocytes with neuraminidase rendered the cells resistant to agglutination by ibv. susceptibility to agglutination was restored by resialylation of ...19921322604
recent studies on the enterotropic strain of avian infectious bronchitis virus.avian infectious bronchitis (aib) is an economically important disease of chickens. recent studies have revealed enterotropism by at least one strain of aib virus with pathological lesions in parts of the gut. this review highlights the findings of the studies so far made on this enterotropic strain of aib virus.19921323167
immune response to oil-emulsion vaccines with single or mixed antigens of newcastle disease, avian influenza, and infectious bronchitis.inactivated newcastle disease virus (ndv), avian influenza virus (aiv), and infectious bronchitis virus (ibv) antigens were evaluated for immunological efficacy in monovalent and polyvalent vaccines. vaccinated broilers were bled for hemagglutination-inhibition (hi) tests at 1- or 2-week intervals. half of the chickens were challenged with the largo isolate of velogenic viscerotropic (vv) ndv at 8 weeks post-vaccination, and the remainder were challenged with the massachusetts 41 strain ibv at 9 ...19902157390
antigenic domains on the peplomer protein of avian infectious bronchitis virus: correlation with biological functions.monoclonal antibodies (mabs) directed against structural proteins of infectious bronchitis virus (ibv) were produced to analyse the antigenic structure of this virus. competitive binding of enzyme-labelled and unlabelled mabs to ibv peplomer protein was analysed in an antibody binding assay to test the relatedness of the epitopes defined by the mabs. based on the competition groups, eight epitope clusters were defined (s-a to s-h); six of these clusters (s1-a to s1-f) were located on the s1 subu ...19901698920
immunization of day-old chicks having maternally derived antibodies against infectious bronchitis: degree of protection as monitored by ciliary activity after intratracheal chicks with maternally derived antibodies were vaccinated against infectious bronchitis (ib) with 3000 eid50 of the ib vaccine virus designated h120. the degree of protection induced by intranasal-eye drop (ie) vaccination was compared to that achieved by spray (s) vaccination. the protection afforded by vaccination was monitored by intratracheal challenge with ibv strain m-41 (clinical signs, ciliary activity in tracheal explants, virus isolation) and by serological tests (ovoneutra ...19911661062
comparative infectivity for axenic and specific-pathogen-free chickens of o2 escherichia coli strains with or without virulence factors.adhesion to epithelial respiratory cells, iron acquisition, and production of k1 polysaccharide capsules have been proposed as potential virulence factors of avian escherichia coli. these factors were studied by inoculating groups of axenic or specific-pathogen-free (spf) chickens intratracheally with o2 e. coli strains after previous challenge with a wild strain of infectious bronchitis virus (ibv). in all experiments, the association between ibv and an e. coli strain endowed with the three vir ...19892522766
cross-protection studies with vaccine strain h-120 of infectious bronchitis virus using ciliary activity.forty 3-day-old chickens were immunized intratracheally and another 40 intranasally-intraocularly with vaccine strain h-120 of infectious bronchitis virus (ibv). the chickens were divided into groups of five and each group was challenged intratracheally or intranasally-intraocularly with one of 8 different heterologous strains of ibv 4 weeks after vaccination. the vaccinated chickens were protected against challenge with three heterologous strains (massachusetts m41, b and aeg), showing 89, 86 a ...19911661063
efficacy of australian vaccines against recent isolates of avian infectious bronchitis viruses. 19911653564
avian infectious bronchitis: cross-protection studies using different australian subtypes.the cross-immunity of vaccinated chickens after challenge with some australian infectious bronchitis viruses was assessed by humoral antibody responses and by ciliary activity in tracheal rings of vaccinated chickens following challenge. four viruses were used for vaccination: vac 3, vac 4, both current infectious bronchitis vaccine viruses, and q1/76 and n2/62. ibv n1/62 (synonym t0 and infectious bronchitis virus n9/74 (synonym appin) were used to challenge the vaccinated chickens. results sho ...19892559688
pathogenicity of escherichia coli in aerosols for young chickens.the relative pathogenicity of esherichia coli isolates from poultry was determined by aerosol exposure of young chickens. evidence of colisepticemia with airsacculitis and/or pericarditis and perihepatitis was evaluated. a system was devised that included the intratracheal (it) inoculation of strain se-17 infectious bronchitis virus (ibv) of chicks at 7 days of age followed by their aerosol exposure to e. coli culture suspensions 2 days later. each experiment was terminated 6 days later. for com ...19892559703
x-ray microanalytical investigation of the response of chicken proximal tubule cells to infection with avian infectious bronchitis virus.the technique for x-ray microanalysis of frozen-hydrated bulk specimens was used to determine the intracellular and luminal fluid electrolyte concentrations in the proximal tubules of kidneys from chickens infected with infectious bronchitis virus. eight days post-infection with this virus there were significant changes in the electrolyte composition when compared with values from normal control chickens. the intracellular sodium decreased from 43 to 36 mmol/l, the chloride fell from 41 to 31 mm ...19911645225
virulence and transmissibility of mycoplasma gallisepticum.the virulence of 4 low passage strains of mycoplasma gallisepticum obtained from different sources within australia was studied by experimental infection of chickens. strain ap3as, originally isolated from the air sac of a broiler chicken, produced severe air sac lesions following injection into the abdominal air sacs of 2-week or 3-week-old chickens, and adult hens. strain 80083 which was isolated from a clinically normal broiler breeder hen was also capable of producing gross air sac lesions f ...19892712773
the susceptibility of chicken kidney and oviduct organ cultures to a vaccine strain of avian infectious bronchitis virus.the minimal infectious dose of the h52 strain of infectious bronchitis virus for organ cultures of oviduct and kidney was compared in chickens of different ages. organ cultures of oviduct were found to be highly susceptible to infection regardless of the age of chicken and no difference in susceptibility could be demonstrated between cultures of the magnum and uterus regions of the mature oviduct. kidney organ cultures were less susceptible and resistance to infection increased significantly (p ...1979224435
attenuation of avian infectious bronchitis virus by cold-adaptation.avian infectious bronchitis virus (ibv) arkansas-type dpi strain was passaged 10 times in specific-pathogen-free (spf) chicken embryos incubated at 28 c and 37 c. virus grown at 28 c acquired cold-adapted (ca) and temperature-sensitive (ts) characteristics based on more-rapid growth at 28 c and a reduced ability to grown at 41 c, respectively, compared with non-cold-adapted (non-ca) virus grown at 37 c. the pathogenicity and immunogenicity were determined for ca and non-ca ibv in 1-day-old spf c ...19911664720
action spectrum of antiviral factor from chicken sera.rous sarcoma virus infections of regressor line chickens stimulate the transient production of antiviral factors in the serum. earlier the present authors reported that a viral neutralization factor (vnf) inactivated rous sarcoma virus during a 3-h incubation. the vnf is likely to have a broad antiviral and antimicrobial spectrum because it is active against several unrelated pathogenic poultry viruses. the present study measured the activity of vnf against newcastle disease virus, infectious bu ...19911664518
determination of the antigenic relationships among six serotypes of infectious bronchitis virus using the enzyme-linked immunosorbent assay and serum-neutralization test.the indirect enzyme-linked immunosorbent assay (elisa) was applied to detect antibody to infectious bronchitis (ib) virus in chickens. a cross-reactivity study was performed to determine the antigenic relationships among six strains: massachusetts, connecticut, beaudette, and three ontario field isolates. for comparison, the cross-reactivity study was performed in eggs using the serum-neutralization (sn) test for ib. the elisa proved to be more broadly cross-reactive than the ib-sn test. this su ...19872823768
serum antibody responses of chickens following sequential inoculations with different infectious bronchitis virus serotypes.sequential inoculations of chickens with different live infectious bronchitis virus (ibv) antigenic types had major effects on virus-neutralization (vn) and hemagglutination-inhibition (hi) serum antibody responses. antibody production in ibv-inoculated chickens that were reinoculated 8 weeks later with heterologous virus was largely directed against the virus used for initial inoculation rather than the virus used for reinoculation. in addition, chickens inoculated sequentially with ibv produce ...19872823771
studies of avian urolithiasis associated with an infectious bronchitis virus.avian urolithiasis syndrome was diagnosed in 14-to-25-week-old chickens from a multiple-age caged-layer complex housing more than 2.5 million chickens. losses from this syndrome ranged from 0.5 to 1.0% per week. seven-to-14-week-old pullets from this facility had multifocal renal tubular necrosis leading to interstitial fibrosis, tophus formation, and tubular dilation. a coronavirus was isolated in embryos inoculated with pooled samples of trachea, kidney, and cecal tonsil of 4-week-old pullets. ...19872823778
localization of a t-cell epitope within the nucleocapsid protein of avian a previous study, two murine t-cell hybridomas generated after immunization with infectious bronchitis virus (ibv) were shown to be responsive to the internally localized viral nucleocapsid protein. in the present study, the antigenic determinants were mapped using recombinant expression products and synthetic peptides. both hybridomas recognized the region spanning amino acid residues 71 to 78 of the nucleocapsid protein. the experimentally determined epitope corresponded with predicted moti ...19911718856
investigations into resistance of chicken lines to infection with infectious bronchitis virus.although nine inbred and partially inbred lines of chickens were equally susceptible initially to infection with infectious bronchitis virus (ibv), the outcome of that infection varied considerably between the lines. a more detailed study of a line which was resistant (line c) and one which was highly susceptible (line 15i) confirmed that both lines could be infected initially with ibv but showed that the respiratory tract epithelium of line c chicks recovered more rapidly than that of line 15i ...19901966442
typing of recent infectious bronchitis virus isolates causing nephritis in chicken. 19911681795
a model for determining immunogenic relationships between avian infectious bronchitis viruses.a model for determining immunogenic relationships between strains of infectious bronchitis virus is described that is based upon the vaccinating dose required to induce prevention of multiplication of a standard challenge dose of an homologous strain in the lungs of specific-pathogen-free chickens. the model has been used to demonstrate that: (1) approximately 100 times the vaccinating dose must be used to produce immunity from one compared with two doses; (2) differences of immunogenicity of gr ...19902162161
a monoclonal antibody-based immunoperoxidase procedure for rapid detection of infectious bronchitis virus in infected tissues.a monoclonal antibody (mab)-based indirect immunoperoxidase (ip) procedure was applied to detect infectious bronchitis virus (ibv) antigen in frozen tissue sections. with this procedure, ibv antigen could be detected in chorioallantoic membranes (cams) within 15 hr postinoculation and in the respiratory tissues of chickens within 96 hr postinoculation. endogenous peroxidases in chicken tissues were removed by treatment with periodic acid. the ip technique was highly sensitive, convenient, and ec ...19902177975
avian infectious bronchitis diagnosis using an enzyme immunoassay on nitrocellulose. 19882844040
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