title: Avian infectious bronchitis in specific-pathogen-free chickens: quantitation of serum immunoglobulins by electroimmunoassay.
abstract: Immunoglobulin (Ig) levels in serums of individual 6-week-old specific-pathogen-free (SPF) chickens differed markedly. Quantitation by electroimmunoassay showed that the IgG level was quite low at 6 weeks of age (1.3 +/- 0.67 mg/ml), increased gradually with maturity, and by 16-18 weeks of age was 2.6 +/- 1.5 mg/ml. IgM levels were less variable during the same observation period (6-18 weeks, 2.4 +/- 0.50 to 2.2 +/- 0.86 mg/ml). IgA was high initially and decreased with age (6-18 weeks, 0.74 +/- 0.78 to 0.26 +/- 0.06 mg/ml). Single intratracheal vaccination with a moderate dose of live avian infectious bronchitis virus (IBV) and subsequent challenge-exposure with live virus via the respiratory tract did not markedly affect Ig levels. Birds vaccinated parenterally 2 or 3 times with live or killed IBV vaccines had a marked increase in serum IgG after similar challenge-exposure. IgA and IgM levels in vaccinated SPF birds approximated those in control SPF birds throughout the experimental period.
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis; D002645:Chickens / Q000276:immunology*; D003332:Coronaviridae / Q000276:immunology*; D003333:Coronaviridae Infections / Q000276:immunology / Q000662:veterinary*; D007122:Immunoelectrophoresis; D007070:Immunoglobulin A / Q000032:analysis; D007074:Immunoglobulin G / Q000032:analysis; D007075:Immunoglobulin M / Q000032:analysis; D007136:Immunoglobulins / Q000032:analysis*; D001351:Infectious bronchitis virus / Q000276:immunology*; D011201:Poultry Diseases / Q000276:immunology*; D013047:Specific Pathogen-Free Organisms; D014611:Vaccination / Q000662:veterinary
chemical_list: D000914:Antibodies, Viral; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007136:Immunoglobulins