ABSTRACT
Twenty-day-old susceptible chickens were divided into three groups; two were vaccinated with inactivated, water in oil emulsified La Sota strain of Newcastle disease virus (NDV) obtained from a bovine embryo kidney (BS/BEK) cell line and from chicken embryos, respectively. The third unvaccinated group represented the control. At 30-day intervals subgroups were exposed to the Herts 33 virulent NDV strain. Serological and clinical findings showed no appreciable difference in the immunogenicity of the antigen from either culture systems and no significant differences could be observed in its ability to protect against ND challenge.
ABSTRACT
The detection of foot-and-mouth disease virus (FMDV)-persistent carriers among convalescent ruminants is of paramount importance in the aftermath of a field outbreak. To this purpose, FMDV-specific antibody should be investigated first, since virus isolation procedures from such carriers are seriously constrained. The complexity of the overall picture may be compounded by possible emergency vaccinations in the affected areas at the beginning of the outbreak. In this case, it is suggested that mucosal rather than serum antibody be investigated. In fact, we showed that FMDV-infected cattle regularly mount an antibody response in oropharyngeal fluids, in contrast to vaccinated cattle. Antibody could be revealed by neutralization assays and/or an immunoglobulin A (IgA)-specific kinetic enzyme-linked immunosorbent assay (ELISA). Cattle vaccinated once seldom showed a mucosal antibody response, which could be only detected by a total immunoglobulin-specific kinetic ELISA. Very few, if any, cattle showed a mucosal IgA response after repeated vaccinations. Our kinetic, IgA-specific ELISA generally allowed an early detection of FMDV-infected cattle; in particular, it proved to be more sensitive than the usual indirect, antigen-trapping ELISA in experiments on saliva samples.
Subject(s)
Antibodies, Viral/isolation & purification , Carrier State/veterinary , Enzyme-Linked Immunosorbent Assay/methods , Foot-and-Mouth Disease/diagnosis , Oropharynx/immunology , Animals , Carrier State/diagnosis , Carrier State/immunology , Cattle , Cattle Diseases/diagnosis , Cattle Diseases/immunology , Cattle Diseases/prevention & control , Convalescence , Foot-and-Mouth Disease/immunology , Foot-and-Mouth Disease/prevention & control , Immunoglobulin A/isolation & purification , Mouth Mucosa/immunology , Saliva/immunology , VaccinationABSTRACT
Human lymphoblastoid interferon from Namalwa cells was purified for clinical use by ethanol fractionation, and used as adjuvant of an inactivated Bovid Herpesvirus 1 vaccine in calves. In agreement with other in vitro and in vivo models, low and high interferon doses were shown to increase and depress the specific antibody response, respectively. The low, effective interferon dose (100 International Units/kg) also reduced the variability of antibody titres after the first vaccine injection. This latter dose had apparently no influence on the regulatory T cell circuits, as opposed to the other doses under study.
Subject(s)
Adjuvants, Immunologic/administration & dosage , Herpesvirus 1, Bovine/immunology , Interferon-alpha/administration & dosage , Viral Vaccines/administration & dosage , Animals , Antibodies, Viral/biosynthesis , Antigens, Viral , Cattle , Cattle Diseases/prevention & control , Dose-Response Relationship, Immunologic , Herpesviridae Infections/prevention & control , Herpesviridae Infections/veterinary , Humans , In Vitro Techniques , Interferon-gamma/metabolism , Lymphocyte Activation , Vaccines, Inactivated/administration & dosageABSTRACT
Ultramicroscopic structure of a strain (Mn-73) of BPSV grown on calf kidney primary cultures was investigated. Beside young and mature virions, virus particles with intermediate structural characteristics are described. Size of mature particles on electron microscopic photographs resulted of 270-280 X 140-150 nm, that is a little smaller in comparison with Nagington's et al. (1962) and Büttner's et al. (1964) estimations. Such discrepancy seems to arise from technical artifacts.
Subject(s)
Viruses, Unclassified/ultrastructure , Animals , Cattle , Cattle Diseases/microbiology , Kidney , Microscopy, Electron , Stomatitis, Aphthous/veterinary , Virus CultivationABSTRACT
Three of several virus isolates made from different groups of chickens affected with arthritis were serially passaged in chicken embryos, and then cultured on chicken kidney cells with the production of cytopathic effects and development of syncytia. Resistance to inactivating agents and electron microscopic features showed their relationship to reoviruses. By the agar gel diffusion test the isolates were shown to be serologically related to each other and to 2 American strains. A tissue suspension from infected embryos when inoculated into the footpad of one to 15 day-old chicks reproduced arthritis.
Subject(s)
Cattle Diseases/epidemiology , Stomatitis/veterinary , Animals , Cattle , Disease Reservoirs , Stomatitis/epidemiologyABSTRACT
Adaptation to the chicken embryo of a virus strain of infectious bursal disease resulted in a reduction in virulence. After 60 passages the strain was attenuated enough to be used as a vaccine. The attenuation proved adequately stable. If given orally in the drinking water, the strain induced the development of neutralising and precipiting antibodies and a strong resistance against the disease. Promising results have also been obtained in the field.
