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Biomedical subjects

R W Winterfield

Publications and source records attributed to R W Winterfield.

At least 19 recordsLinked to original sources
PubMed1985

Avian pox: infection and immunity with quail, psittacine, fowl, and pigeon pox viruses.

Quail, chickens, and turkeys vaccinated with pigeon and fowl pox viruses were not protected against challenge of their immunity with quail pox virus and they developed severe cutaneous lesions of pox. When quail and chickens were vaccinated with quail pox virus and given pigeon and fowl pox challenge viruses, no protection was present. Thus, quail pox virus had no immunologic relationship to pigeon and fowl pox viruses. Psittacine pox virus applied as a vaccine in quail and chickens also failed to protect against quail pox virus challenge. However, quail, chickens, and turkeys vaccinated with quail pox virus were protected against quail pox virus challenge. An isolate of psittacine pox virus, applied as a vaccine, protected chickens against challenge with the same virus isolate and also against challenge with two other psittacine pox virus isolates, confirming a close or identical antigenic relationship with each other. When combined in a multivalent vaccine, quail, psittacine, and fowl pox viruses induced excellent protection in chickens against challenge with the three respective viruses. The presence or absence of "takes" or reactions following vaccination by the wing web route did not necessarily correlate with the presence or absence of immunity noted from challenge by feather follicle virus application. The role of quail and psittacine pox viruses as potential pathogens for poultry was discussed briefly.

Animals↗
PubMed1985

Infection and immunity with a virus isolate from turkeys.

Avian pox virus was isolated from cutaneous pox lesions removed from turkey breeders that had been vaccinated three times with a commercial fowl pox vaccine. In three cross-immunization experiments with turkeys and two with chickens, the turkey pox isolate, designated NC5271, proved immunologically different from fowl, pigeon, and quail pox viruses. Significant protection against NC5271 virus infection and inducement of pox lesions was only attained when the homologous isolate was used as a vaccine. The potential need in the field for such a vaccine was discussed.

Animals↗
PubMed1978

Vaccination against infectious bronchitis and the immunosuppressive effects of infectious bursal disease.

An 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, if exposed to IBDV, than were those individuals hatched from IBD immune dams. However, in some cases, chickens from IBD immune dams were also more susceptible to IBV challenge when they had been exposed to IBDV and when compared to birds unexposed to IBDV but vaccinated against IB. An effect of cyclophosphamide on the bursa of Fabricius also had an immunosuppressive action on IBV immunity which was similar to the results from IBDV exposure. The data engendered from these trials may explain the unsatisfactory immunity sometimes observed under field conditions when broilers and replacement pullets are vaccinated at an early age.

Animals↗
PubMed1977

Immunization of chickens against adenovirus infection.

Chickens were vaccinated with monovalent and polyvalent adenovirus vaccines using three different serotypes, types 1, 2, and 3. No cross-protection was elicited by the heterologous serotypes but satisfactory protection from lesions and the shedding of challenge virus was induced by the homologous serotypes in the monovalent and polyvalent vaccines. The virus neutralizing (VN) titers were occasionally lower where the polyvalent vaccines were used when compared to those from chickens given the monovalent vaccines. This suggested possible interference though protection did exist against the appearance of lesions. Where chickens were vaccinated at an early age and in the presence of congenital homologous VN antibodies, protection against the effects of infection was satisfactory whereas the VN antibody titers were low or insignificant by the assay methods employed. The vaccine virus was not shed beyond 28 days after vaccination. No physical effects of vaccination were noted in any of the chickens during the post-vaccination period.

Adenoviridae Infections↗
PubMed1976

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 in laboratory trials. The isolant was passed through a 0.22 mu. filter. It was heat (56 C), acid pH (3.0), ether and chloroform labile. In embryos it produced deaths or lesions of infectious bronchitis in one to five days after inoculation. It is suggested that this IBV isolant be designated Indiana-type.

Animals↗
PubMed1975

Potential for polyvalent infectious bronchitis vaccines.

Numerous antigenic types and subtypes of infectious bronchitis virus (IBV) have been isolated and characterized from field epornitics of infectious bronchitis (IB). Thus obvious failures in obtaining the necessary protection from vaccination have been documented and they underscore the urgent need for vaccines which stimulate a broader spectrum of protection from heterologous IBV challenge than is presently obtained. If polyvalent IB vaccines are to be employed, assurance must be provided that variant IBV serotypes are not indiscriminately spread throughout the country or globe. Furthermore, possible interference, alteration, and reduction in immune response with the component antigens should be critically evaluated. Differences and comparative levels of postvaccinal respiratory signs with the different antigens, used singly and in combination, should be determined. As an alternative to polyvalent IB vaccines, certain Massachusetts-type strains, e.g., a Holland isolate IBV, at different passage levels in the authors' laboratory, have induced heterologous and homologous protection to some serotypes causing vexing field problems. Advantages are present in using a single antigenic type IB vaccine, if it is safe and effective, when compared to polyvalent vaccines. The absence of a serologic relationship to the results of immunity challenge is frequent with IBV isolates, which emphasizes that challenge results are considerably more important. In some IB problems, on a local or regional basis, autogenous vaccines may be indicated. Because of the multiplicity of IBV serotypes, however, it is doubtful that completely effective and safe IB vaccines will be forthcoming in the near future to satisfy the diverse needs of a dynamic poultry industry.

Animals↗
PubMed1975

Antigenic characterization of the inclusion body hepatitis virus.

Proof that inclusion body hepatitis of chickens (IBHC) is caused by a virus (IBHV) was established in 1973. Characterization of IBHV has been conducted by employing the standard criteria for virus classification. The results have indicated that IBHV is a member of the avian adenovirus group. However, no antigenic relationship was found between IBHV and two other avian adenovirus isolates (CELO and Indiana C) as observed by hemagglutination (HA) and virus-serum neutralization tests. Another adenovirus isolate was found to be serologically different from IBHV (Tipton strain) but it incited typical IBHC in susceptible chicks. A novel antigen, detectable by the agar gel immunodiffusion test, was demonstrated in livers from chicks infected experimentally with IBHV. This antigen was able to give a specific precipitin reaction with serums from chickens previously exposed to IBHV. Repeated embryo passage of IBHV lowered its pathogenicity for susceptible chickens. Protection of chickens against IBHV challenge was obtained by vaccination with high embryo passage IBHV (Tipton strain). It was also found that subcutaneous administration of the vaccine virus induced a better immune response than the eye-drop route as observed by the virus-serum neutralization index obtained.

Adenoviridae↗
PubMedDate not supplied

Acute copper toxicosis in the Canada goose.

Acute copper toxicosis resulted in Canada geese, Branta canadensis, following ingestion of copper sulfate at about 600mg/kg from a small man-made pond on a game farm. The lesions were those associated with copper toxicosis in other avian species. The primary pathologic change was necrosis and sloughing of the proventriculus and gizzard. A greenish discoloration of the lungs also occurred.

Animals↗
PubMedDate not supplied

The oncogenic potential of some avian adenoviruses causing diseases in chickens.

The oncogenic potentials of three different strains of avian adenoviruses (the Tipton strain of the inclusion body hepatitis virus, the DPI-2, and the Indiana C viruses) were investigated in newborn hamsters. Animal inoculations were via two routes, subcutaneous and intracerebral. All three viruses proved nononcogenic for the hamsters observed over a period of 225 days. However, lesions of hepatitis similar to those of inclusion body hepatitis of chickens were seen in three hamsters inoculated with the DPI-2 virus.

Adenoviridae↗
PubMedDate not supplied

Immunity to infectious bronchitis virus from spray vaccination with derivatives of a Holland strain.

Study 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 homologous IBV antibodies as well as vaccinating susceptible 4-week-old chickens. The tracheal virus shed-rate following challenge was considered low (20% or less) with 4 of the challenge viruses. The challenge virus shed-rate was somewhat higher from vaccination at one day old than from vaccination at 4 weeks; the virus-serum-neutralization titers were lower, or even insignificant, with early-age vaccination. The immunogenicity and virulence of the vaccine virus was apparently reduced in the higher embryo passages employed. None of the vaccine derivatives was considered virulent under these conditions.

Aerosols↗
PubMedDate not supplied

Vaccination and revaccination with a Holland (H) strain of infectious bronchitis virus.

One-day-old 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 in each of the challenged groups (compared with unvaccinated controls). With 5 of the challenge viruses, protection against tracheal virus shed was good (70% or greater). Revaccination at 4 weeks old by the aerosol route with the 53rd and 72nd passages did not greatly enhance protection. However, the virus-serum-neutralizing (VN) titers with Massachusetts-type IBV as an indicator were high, and an anamnestic response was demonstrated at 8 weeks of age. The VN titers observed at 4 weeks old were generally low and did not correlate necessarily with the protection engendered.

Aerosols↗
PubMedDate not supplied

Role of the bursa of Fabricius in the pathogenicity of inclusion body hepatitis and infectious bursal disease viruses.

Chickens were chemically bursectomized with cyclophosphamide at 3 days old, and studies made of the effects of infection by inclusion body hepatitis virus (IBHV) and infectious bursal disease virus. In another experiment, 3-week-old chickens were infected with infectious bursal disease virus before inoculation with IBHV. Interference with the bursa of Fabricius by cyclophosphamide or by infectious bursal disease virus enhanced the pathogenicity of IBHV. In contrast, cyclophosphamide effects on the bursa protected chickens against infectious bursal disease.

Animals↗
PubMedDate not supplied

Pathogenesis of H13 nephropathogenic infectious bronchitis virus.

A nephropathogenic Massachusetts strain of infectious bronchitis virus (IBV) designated H13-IBV was isolated from the kidneys of commercial broilers. H13-IBV caused respiratory distress, depression, and diarrhea in specific-pathogen-free chickens. Gross renal lesions included pale coloration, swelling, and urate deposition. Histologic renal changes were interstitial mononuclear cell infiltration and degeneration and necrosis of tubular epithelial cells. Lesions in respiratory tissues included thickening and edema of the air sacs, congestion of the tracheal mucosa, and frothy serous exudate. Histologic tracheal lesions were deciliation, mucous gland distortion, inflammatory cell infiltration, and squamous metaplasia. Clinically, H13-IBV was highly pathogenic in birds infected at 1 day of age and mildly pathogenic in birds infected at 4 weeks of age. Kidney lesions were of marked severity only in birds infected at 1 day of age. Tracheal lesions were similar in severity in both age groups.

Animals↗
PubMedDate not supplied

Immune response and pathogenicity of different strains of infectious bursal disease virus applied as vaccines.

Eight strains of infectious bursal disease virus (IBDV) were characterized by the criteria of immunity and pathogenicity engendered in young chickens. Some strains have been used commercially, and the others are potential candidates for vaccines. They were administered by drinking water, eyedrop, vent drop, and subcutaneous and aerosol routes. The viruses varied widely in pathogenicity in terms of bursal damage, morbidity, and mortality. Immunity induced with different routes of administration also differed markedly when measured by challenge, virus serum-neutralizing antibody titers, and the agargel precipitin test. Maternally derived immunity interfered with stimulation of active immunity by some of the less pathogenic strains. The more virulent strains, however, were able to provide protection under similar circumstances, although bursal damage was frequently severe. Two strains proved relatively virulent by the criteria employed. Characteristics desirable for IBDV strains to be given as vaccines under field conditions to young chickens are discussed briefly.

Aerosols↗
PubMedDate not supplied

Mycobacterium infection in a gray-cheeked parakeet.

A gray-cheeked parakeet, approximately 3 years of age, was submitted for necropsy. Clinical signs included diarrhea, decreased feed consumption, fluffing of feathers, shivering, weight loss, and limping. Necropsy revealed enlargement and pale discoloration of the spleen and intestines. The liver contained multifocal pale foci. Granulomas, some of which had necrotic centers, were present along the subserosa of the intestinal tract. Microscopic examination revealed diffuse granulomatous splenitis, enteritis, and multifocal granulomatous hepatitis. Numerous acid-fast bacteria were demonstrated in the spleen, liver, and intestine.

Animals↗
PubMedDate not supplied

An outbreak of nephropathogenic H13 infectious bronchitis in commercial broilers.

A nephropathogenic Massachusetts strain of infectious bronchitis virus, designated H13-IB virus, was isolated from the kidneys of broilers in a commercial flock. Respiratory distress, diarrhea, depression, and high mortality were present. Gross renal lesions consisted of pale coloration, mottling, urate deposition, and swelling. The trachea contained a serous to catarrhal exudate. Microscopically, renal changes were primarily associated with the medullary region. Lesions included an interstitial mononuclear cell infiltration, urate deposition, edema, and degenerative and necrotic tubular changes. Tracheal changes included marked thickening of the mucosa, desquamation of ciliated and glandular epithelia and replacement with a stratified undifferentiated epithelium, and inflammatory cell infiltration.

Animals↗
PubMedDate not supplied

Relationship between delayed onset of egg production and involution of the bursa of Fabricius in White Leghorn chickens.

The relationship between delayed onset of oviposition and involution of the bursa of Fabricius is described. Chickens studied were 26 weeks of age and had not come into production. The bursae of nonlaying chickens were compared with those of age-matched chickens that had laid the first egg 1, 9 to 11, or 24 days before. The bursae from the nonlaying chickens were similar in weight and morphology to the functional bursae of immature pullets. Bursae of laying chickens, even on the day of the first egg, were markedly involuted. Age of the chicken was not a factor in determining bursal involution. The onset of egg production was directly related to bursal involution.

Animals↗