title: Efficacy of isolated colostral IgA, IgG, and IgM(A) to protect neonatal pigs against the coronavirus of transmissible gastroenteritis.
abstract: To ascertain what class of immunoglobulin (Ig; IgA, IgG, or IgM) is most efficacious in protection, a large quantity of colostrum from sows immunized with virulent transmissible gastroenteritis (TGE) virus was fractionated by chromatographic and gel filtration methods. The isolated IgG, IgA, and IgM(A) had specific virus-neutralizing activities of 1:7.6, 1:342, and 1:302 per milligram of protein, respectively. Each Ig was fed to groups of hysterectomy-derived colostrum-deprived neonatal pigs before and after exposure (challenge) with virulent TGE virus. The 7 pigs fed IgG survived the challenge exposure, but 2 of 7 fed IgA and 1 of 7 fed IgM(A) died of TGE. Three of the survivor pigs that had been fed IgG and 2 of the survivor pigs that had been fed IgA had increased serum antibody titers between 8 and 19 days after challenge exposure, but none of the survivor pigs fed IgM(A) had TGE antibody. In contrast, 12 of 14 virus-control pigs died of TGE and the 2 survivors had antibody conversion. The data show that all 3 Ig classes in immune colostrum will protect neonatal pigs against exposure with virulent TGE virus.
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D000917:Antibody Formation; D003126:Colostrum / Q000276:immunology*; D005260:Female; D005761:Gastroenteritis, Transmissible, of Swine / Q000276:immunology / Q000517:prevention & control*; D007116:Immunization, Passive; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D011247:Pregnancy; D013552:Swine; D014611:Vaccination / Q000662:veterinary
chemical_list: D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M