Ontogeny of Mink IgG,IgA,and IgM

Abstract

Summary

Serum levels and [¹⁴C] tissue culture synthesis of IgG, IgA and IgM were determined in pre- and postnatal normal mink. Small amounts of IgG were found in serum from fetal and neonatal mink prior to suckling. This could represent maternal Ig (transplacental) or could be autologous Ig as IgG synthesis was found in day old kit spleen and lymph node tissues. The suckling kit achieved adult levels of IgG (7-10 mg/ ml) 8 days after birth although IgG then decreased (before weaning) to 1-2 mg/ml during the fifth week of life. Generous amounts (mean 2.9 mg/ml) of IgG were found in mink milk throughout the nursing period. Small amounts of IgA (mean 0.17 mg/ml) were also found in mink milk, although IgA was not detectable in kit serum until 39 days of age and IgA synthesis in [¹⁴C] tissue culture was not found in tissues from kits less than 75 days of age. IgM was not detected in milk, although [¹⁴C] tissue culture synthesis of IgM was consistently found 1-2 days postpartum and serum levels gradually increased during neonatal development.