Biomedical subjects

C S Eidson

Publications and source records attributed to C S Eidson.

At least 19 recordsLinked to original sources

PubMed1985

Simultaneous application of live turkey herpesvirus and infectious bursal disease vaccines against Marek's disease and infectious bursal disease.

The efficacy of cell-associated (CA) and cell-free (CF) infectious bursal disease (IBD) vaccines in maternal antibody (MAb)-bearing broiler chickens was compared. Compatibility and potency of a mixed vaccine combining live CA turkey herpesvirus (HVT) and CA IBD vaccine viruses were also tested against gross lesions induced by Marek's disease (MD) or IBD in specific-pathogen-free chickens. Both CA and CF IBD vaccines provided significant protection against gross bursal lesions of IBD in the presence of MAb. Although chickens receiving the CA vaccine showed a slightly higher (60 to 86.7%) protective index (PX) than CF vaccine recipients (40 to 66.7%), there was no statistical difference in their PX between comparable CA and CF IBD vaccines. The HVT and IBD virus (IBDV) were compatible when they were combined as a live bivalent mixed HVT-IBDV vaccine. Based on the incidence of gross lesions induced by challenge exposure to MD or IBD, potency of the mixed vaccine was similar to that of the monovalent HVT or IBD vaccine. Antagonism did not occur between the two component vaccines when they were applied simultaneously.

Animals↗

PubMed1985

Vaccination against Marek's disease and infectious bursal disease III. Growth rate of both turkey herpesvirus and infectious bursal disease virus in coinfected cell cultures.

Titers of the turkey herpesvirus (HVT) and infectious bursal disease virus (IBDV) in coinfected cell cultures, used to produce a live bivalent HVT/IBDV vaccine, were determined daily. Based on the daily titers, cells harvested either 2 or 3 days after inoculating the second virus (IBDV) into HVT infected cell cultures yielded the maximum titers for both viruses. Harvesting coinfected cell cultures on either day provided the most suitable source of the live HVT/IBDV vaccine against Marek's disease and infectious bursal disease.

Animals↗

PubMed1985

Performance of broiler progeny of breeder flocks vaccinated with inactivated oil emulsion malabsorption syndrome virus vaccine.

Broiler breeder pullets were vaccinated at 20 to 24 weeks of age with an inactivated, oil emulsion vaccine containing the CO8 strain of avian reovirus. The vaccination induced a high and uniform antibody response that peaked 4 to 5 months postvaccination and persisted up to 11 months postvaccination. Broiler production parameters in progeny of vaccinated breeders were compared weekly with parameters of the total broiler production. There was a consistent improvement in body weight at processing time and a reduction in total production cost in progeny of vaccinated parents. There was also a reduction of percent of parts condemned during the first part of the trial. There were no consistent differences in feed conversion or condemnation of whole carcasses. Progeny of vaccinated parents had reduced livability. This effect was interpreted to be due to the smaller egg size of young breeder flocks.

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PubMed1984

Vaccination against Marek's disease and infectious bursal disease. II. Titration and in vivo efficacy of the coinfection-derived bivalent live vaccine for turkey herpesvirus and infectious bursal disease virus.

The bivalent HVT/IBDV live vaccine, developed by cocultivation of the turkey herpesvirus (HVT) and infectious bursal disease virus (IBDV) vaccine in cell cultures, was quantitated. The titer of each constituent virus could be successfully determined in vitro by pretreatment of the vaccine with anti-IBDV serum or chloroform (CHCl3). Studies in vivo further demonstrated that the anti-IBDV serum-treated HVT/IBDV vaccine lost its immunogenicity by failing to induce IBDV-neutralizing antibody or to protect vaccinates from bursal atrophy after challenge exposure to infectious bursal disease. The CHCl3 treatment significantly reduced the efficacy of the vaccine to protect vaccinates against Marek's disease challenge.

Animals↗

PubMed1983

Simultaneous vaccination of one-day-old broiler chickens with tenosynovitis virus and turkey herpesvirus.

An attenuated tenosynovitis virus vaccine and turkey herpesvirus (HVT) vaccine mixed prior to vaccination were injected subcutaneously into one-day-old chicks. In laboratory and field trials there did not appear to be any interference, because chickens vaccinated with both vaccines were effectively immunized against challenge with virulent Marek's disease virus or tenosynovitis virus when compared with unvaccinated chickens or chickens vaccinated with either HVT or tenosynovitis virus. The combined tenosynovitis and HVT vaccine had essentially the same virus titers when compared to the titers of each vaccine prior to mixing. Also, the HVT viremia levels and the serum neutralization titers of chickens vaccinated with both vaccines were essentially the same as those in chickens vaccinated with a single vaccine. In field trials, chickens vaccinated with the combined vaccines had fewer condemnations for parts and septicemia-toxemia and total condemnations when compared to chickens not vaccinated with tenosynovitis virus. There was less mortality in the majority of the flocks vaccinated with tenosynovitis virus vaccine and HVT when compared to flocks receiving only HVT vaccine.

Animals↗

PubMed1983

Multivalent inactivated virus oil emulsion vaccines in broiler breeder chickens. I. Newcastle disease virus and infectious bursal disease virus bivalent vaccines.

Inactivated Newcastle disease virus (NDV) and infectious bursal disease virus (IBDV) were incorporated into water-in-oil emulsion vaccines alone or as a bivalent vaccine. Twenty-week-old broiler breeder chickens that had received previous live virus vaccination with NDV and IBDV were injected intramuscularly with the monovalent or bivalent vaccine. The antibody titers to either the monovalent vaccine or bivalent vaccine increased rapidly and then remained at high levels for the duration of the 40-week trial. There were no practical differences in amplitude or duration of the antibody response to either antigen used alone compared to that of the bivalent combination. Progeny hatched from the vaccinated breeders possessed maternal antibody levels at one day of age comparable to those of the hens at the time the eggs were laid. The maternal antibody titers declined at a steady rate until they reached negligibly detectable levels at approximately 3 weeks of age. This trend held true without regard to the initial antibody titer.

Animals↗

PubMed1983

Multivalent inactivated virus oil emulsion vaccines in broiler breeder chickens. II. Trivalent vaccines in breeders not previously vaccinated with live Newcastle disease, infectious bursal disease, and tenosynovitis vaccines.

Inactivated Newcastle disease (NDV), infectious bursal disease (IBDV), and viral arthritis/tenosynovitis (VA) viruses were incorporated into water-in-oil emulsion vaccines either alone, in bivalent combinations, or in a trivalent vaccine. Twenty-week-old broiler breeder chickens with no previous exposure to NDV, IBDV, or VA live virus vaccines were injected intramuscularly with the monovalent, bivalent, or trivalent vaccines. The antibody responses to NDV in all three vaccines were poor, and NDV-hemagglutination-inhibition (HI) geometric mean titers (GMTs) never rose above 20 during the 40-week trial. The antibody response to IBDV showed a strong primary response 4 weeks after vaccination, but IBD-VN geometric mean titers declined steadily to less than 100 by 4 months after vaccination. The antibody GMTs to IBDV continued to decline for the remainder of the trial. The antibody response to VA virus was biphasic, with peak VA-virus neutralization (VN) geometric mean titers occurring at 3 months and 6 months postvaccination. The amplitude of the response to the monovalent, bivalent, and trivalent vaccines was inversely proportional to the number of antigens incorporated into each vaccine. Maternal antibody titers in the progeny against each of the three antigens reflected those of the parents. In no case were maternal antibody titers detectable beyond 14 days of age.

Animals↗

PubMed1983

Multivalent inactivated virus oil emulsion vaccines in broiler breeder chickens. III. Trivalent Newcastle disease, infectious bursal disease, and arthritis/tenosynovitis viruses vaccine in primed breeders.

Animals↗

PubMed1983

Vaccination against Marek's disease and infectious bursal disease. I. Development of a bivalent live vaccine by co-cultivating turkey herpesvirus and infectious bursal disease vaccine viruses in chicken embryo fibroblast monolayers.

Vaccine viruses of Marek's disease (MD), the FC-126 strain of the herpesvirus of turkeys (HVT), and infectious bursal disease (IBD), the Bursa-Vac-M strain of IBD virus (IBDV), were propagated in the same chicken embryo fibroblast (CEF) monolayers by superinfection. Co-infection of the two viruses in the same CEF culture or in a single cell can be demonstrated by staining with acridine orange and by electron microscopy.l This study was conducted with a superinfected live bivalent vaccine (HVT/IBDV) in one-day-old specific pathogen-free (SPF) and conventional White Leghorn (CWL) chicks. Chickens vaccinated with HVT/IBDV produced persistent HVT viremia for at least 6 weeks postvaccination; significantly higher IBD virus neutralizing antibody levels were observed for the entire 8-week experimental period when compared to unvaccinated controls. Differences between virus neutralizing antibody titers stimulated by HVT/IBDV and IBDV alone were not statistically significant in SPF chickens; however, due to maternal antibody there were some significant differences in CWL chickens. Both the HVT/IBDV bivalent vaccine and the monovalent IBDV vaccine protected the chickens against challenge with virulent IBDV. Based on microscopic lesions and bursa: body weight indexes, challenge of vaccinated chickens with virulent IBDV caused no atrophy in the bursa of Fabricius, but severe tissue destruction was observed in unvaccinated challenged controls. Chickens vaccinated with HVT/IBDV vaccine or with HVT alone were effectively protected against MD when compared to the controls.

Animals↗

PubMed1982

Further studies with an inactivated oil emulsion Newcastle disease vaccine in broiler breeders.

Chickens vaccinated with a live Newcastle disease (ND) vaccine and subsequently revaccinated with an inactivated oil emulsion ND vaccine had higher and more persistent hemagglutination-inhibition (HI) antibody titers than birds vaccinated with live ND vaccine. The geometric mean HI antibody titers of flocks vaccinated with the inactivated ND vaccine ranged from 121 to 172, whereas the titers of flocks vaccinated every 90 days with a live ND vaccine ranged from 18 to 54. Breeder flocks revaccinated with live LaSota ND vaccine had lower egg production than the flocks vaccinated with inactivated vaccine. The average egg production per hen for the 40-week laying cycle was 174 and 170 eggs per hen for hens in the two houses vaccinated with the inactivated vaccine. Hens vaccinated with the live virus vaccine averaged 167 and 164 eggs per hen. The increase in egg production would more than offset the additional cost of the oil emulsion ND vaccine as well as the cost of injecting each individual bird at 18 weeks of age. Between 8 and 32 weeks after onset of egg production, geometric mean maternal antibody titers in 1-day-old chickens derived from breeders vaccinated with live ND vaccine ranged from 7 to 24, whereas, chicks from breeders vaccinated with the inactivated oil emulsion vaccine had maternal antibody titers that ranged from 64 to 89.

Animals↗

PubMed1982

Vaccination of broiler chicks from breeder flocks immunized with a live or inactivated oil emulsion Newcastle disease vaccine.

One-day-old chicks used in this study were from breeder flocks vaccinated with live (B1 and LaSota) or inactivated oil emulsion Newcastle disease (ND) vaccine. Chicks were vaccinated against ND by various procedures. The vaccination response was evaluated by hemagglutination-inhibition antibody titers and by challenge. Chicks from breeder flocks vaccinated with live virus vaccine had a geometric mean hemagglutination-inhibition antibody titer (GMT) for Newcastle of 7 (low maternal antibody titer) at 1 day of age, whereas those chickens derived from breeder flocks vaccinated with inactivated oil emulsion ND vaccine had a GMT of 84 (high maternal antibody titer). One-day-old chicks injected with live B1 vaccine were not immunized against ND regardless of breeder flock source. However, chickens with low maternal antibody titers were effectively immunized against ND when injected at 1 day of age with an inactivated or inactivated plus live ND vaccine. Chicks with high maternal antibody titers were not effectively protected when vaccinated with inactivated vaccine at 1 day of age; however, these chicks were protected when injected with a combined live and inactivated ND vaccine. Chicks from both breeder flocks were effectively immunized against ND when injected at 1 day of age with a live or inactivated ND vaccine and revaccinated by aerosol at 21 days of age with live B1 ND vaccine. Even though they were protected against ND, there appears to have been an interference phenomenon in chicks derived from breeder flocks vaccinated with the live ND vaccine. Beak-O-Vac vaccinated chickens were not effectively protected against ND when compared with chicks vaccinated by aerosol at 1 day of age. Water vaccination at 7, 14, or 21 days of age was as effective as aerosol vaccination when administered to chicks with low maternal antibody titers. However, water vaccination was not as effective as aerosol vaccination when administered to chicks with high maternal antibody titers.

Administration, Oral↗

PubMed1982

Marek's disease tumors in chickens vaccinated with turkey herpesvirus vaccine.

This study evaluated the protective ability of cell-free and cell-associated turkey herpesvirus (HVT) vaccine against Marek's disease (MD). Four variables were evaluated: cell-free versus cell-associated HVT; dose of HVT; time of exposure to MD virus (MDV), and comparison of MD challenge virus types. It was determined that gross lesions of MD were more prevalent in chickens placed in an environment at one day of age with three-week-old chickens shedding the CPF-1 isolate of MD, as in chickens given the same doses of the cell-free and cell-associated HVT vaccine but challenged subcutaneously at 2 weeks of age. The results were not significantly influenced by administering larger doses of the HVT vaccine. The CPF-1 isolate of MD was compared with the GA isolate of MD in chickens vaccinated with graded doses of HVT. Challenge with MDV strains was also with graded doses. Both isolates of MD were similar in virulence. However, protection afforded against MD lesions by HVT was significantly lower in chickens challenged with CPF-1 than with the GA isolate.

Animals↗

PubMed1981

Reduced vaccinal protection of turkey herpesvirus against field strains of Marek's disease herpesvirus.

Four isolates of Marek's disease herpesvirus (MDV) were obtained from 21-week-old broiler breeders with lesions and mortality from Marek's disease (MD). They had been properly vaccinated with turkey herpesvirus (HVT). The isolates were designated Ala-7, 8, 9, and 10. These 4 MDV strains were compared with the GA isolate of MDV in chickens vaccinated with graded doses of HVT. Challenge with the MDV strains was also with graded doses. All 5 isolates of MDV were similar in virulence. However, protection afforded against MD lesions by HVT was significantly lower in the Ala-7, 8, and 9 isolates than with the Ala-10 or GA isolates. The Ala-7, 8 and 9 isolates of MDV induced small-cell plaques in chick embryo fibroblasts, the Ala-10 isolate induced both large and small cell per plaque types, and the GA isolate produced predominantly small cell plaques with a few plaques of the large cell type.

Animals↗

PubMed1981

Serological responses to Mycoplasma synoviae in chickens infected with virulent or avirulent strains of Marek's disease virus.

The pathogenicity and immunosuppressive capability of five strains of Marek's disease herpesvirus (MDHV) was examined. Three of the strains (ALA, MISS, NCS) were isolated from flocks experiencing vaccine breaks while the other two strains (GA, HN) represented prototype virulent and avirulent viruses. Pathogenicity of MDHV strains was evaluated on their ability to cause mortality, their ability to cause gross or microscopic lesions, and the median latent period to death (MLPD) for each strain. Antibody responses to Mycoplasma synoviae (MS) were tested by the serum plate agglutination and hemagglutination inhibition tests. Chicks infected with the virulent strains of MDHV had greater mortality, greater lesion incidence, and shorter MLPD that did chicks infected with the avirulent HN strain. Infection with virulent strains reduced the antibody response to MS and caused severe bursal lesions. Chicks infected with the avirulent HN strain exhibited a slight immunosuppression, but they had no evidence of bursal destruction.

Animals↗

PubMed1980

Field trials with an oil emulsion Newcastle disease vaccine in broiler breeders.

Chickens vaccinated with live Newcastle disease (ND) vaccine and subsequently revaccinated with an inactivated oil emulsion vaccine had high and persistent hemagglutination-inhibition (HI) antibody titers for at least 40 weeks. The geometric mean HI antibody titers of flocks vaccinated with the inactivated ND vaccine ranged from 48.8 to 91.9, whereas the titers of flocks vaccinated every 90 days with a live ND vaccine ranged from 8.6 to 43.5. Breeder flocks revaccinated with a liver LaSota ND vaccine had lower egg production than the flocks vaccinated with the inactivated vaccine. The average egg production per hen for the 40 week laying cycle was 177.8 and 174.8 eggs per hen for hens vaccinated with the inactivated vaccine, whereas those hens vaccinated with the live virus vaccine averaged 163.0 and 155.6 eggs per hen. The increase in egg production would more than offset the additional cost of the oil emulsion NDV vaccine as well as the cost of injecting each individual bird at point of lay. Maternal antibody titers in one-day-old chicks were related to the titers in the dams. Maternal antibody titers in chicks originating from breeder flocks vaccinated with the oil emulsion vaccine were higher than the maternal antibody titers of chickens from breeders vaccinated with the live NDV vaccine.

Animals↗

PubMed1980

Vaccination of chickens with a clone-selected Lastoa strain of Newcastle disease virus.

A cone-selected Lasota strain of Newcastle disease (ND) was found to be more immunogenic than the B1 strain but less immunogenic than the regular Lasota strain while having the same pathogenic index as the B1 strain. The geometric mean hemagglutination-inhibition (HI) titers induced in chickens vaccinated with the cloned Lasota strain were higher than those induced in chickens vaccinated with the B1 strain but were found to be slightly less than the titers obtained in chickens vaccinated with the regular Lasota strain. The clone-selected Lasota strain had essentially the same spreading potential as the regular Lasota strain, as indicated by geometric mean titers and challenge mortality of nonvaccinated chickens which were placed in contact with the vaccinated chickens. Oral, ocular, or aerosol vaccination of maternally immune chickens with the clone-selected Lasota strain gave essentially the same protection as those vaccinated with the regular Lasota strain.

Animals↗

PubMed1980

Comparison of inactivated and live infectious bursal disease virus vaccines in White Leghorn breeder flock.

Leghorn breeder chickens, which had received live infectious bursal disease (IBDV) virus vaccine at 12 weeks of age and had been injected subcutaneously at 20 weeks of age with an inactivated IBDV oil emulsion vaccine, produced very high antibody titers which persisted for at least 9 months and were more uniform than those obtained from breeders receiving only the live IBDV vaccine. Breeders vaccinated with the inactivated IBDV oil emulsion vaccine at 12 and 20 weeks of age had antibody titers higher than breeders which received only the live IBDV vaccine at 12 weeks of age; titers were lower than in the group which received both the live and inactivated oil emulsion IBDV vaccines. Maternal antibody levels in chickens derived from parent flocks vaccinated with the inactivated oil emulsion IBDV vaccine were higher and more uniform than in chickens derived from parent flocks vaccinated with the live IBDV vaccine. Maternal antibody persisted longer in chickens derived from parent flocks vaccinated at 20 weeks of age with the inactivated oil emulsion IBDV vaccine than in chickens vaccinated by the other procedures. The titers remained quite high up to 16 days of age.

Animals↗

PubMed1979

Local antibody response in chickens: analysis of antibody synthesis to Newcastle disease virus by solid-phase radioimmunoassay and immunofluorescence with class-specific antibody for chicken immunoglobulins.

The antibody response to Newcastle disease virus was monitored in the sera and salivas of adult chickens immunized by two methods: (i) combined intratracheal-intranasal vaccination followed by intratracheal revaccination or (ii) intramuscular vaccination followed by intratracheal revaccination. By solid-phase radioimmunoassay, only immunoglobulin G (IgG) and IgA antibodies to Newcastle disease virus were detected in the salivas, whereas IgA and IgM antibodies were present in egg whites. The first method produced the highest antibody levels in both serum and saliva and, in addition, prevented detectable virus multiplication in the respiratory tracts upon revaccination 4 weeks later. Plasma cells of all three classes were distributed throughout the tissues lining the oral cavities. The highest densities of plasma cells were in the Harderian glands; IgG was the predominant class, whereas IgA and IgM plasma cells were present in almost equal but lower numbers. The Harderian plasma cells were the most likely source of the antibody found in saliva.

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