EFFICACY OF ISOLATED COLOSTRAL IGA, IGG, AND IGM(A) TO PROTECT NEONATAL PIGS AGAINST CORONAVIRUS OF TRANSMISSIBLE GASTROENTERITIS

  • 1 January 1977
    • journal article
    • research article
    • Vol. 38 (9), 1285-1288
Abstract
To ascertain what class of immunoglobulin (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/mg 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 were fed IgG and 2 of the survivor pigs that were 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. Of 14 virus-control pigs, 12 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.