ABSTRACT: Western blot analysis of the yolk extract of coho salmon eggs revealed the presence of an immunoglobulin-like protein molecule that reacted with antibodies specific for coho serum immunoglobulin (IgM). Sucrose gradient ultracentrifugation analysis of the yolk extract showed that the molecule 'sedimented' in a manner similar to bovine serum immunoglobulin IgG. This indicates that coho salmon eggs contain a low molecular weight form of serum IgM, perhaps a breakdown product, or a precursor of IgM. The precise function of the reported intra-ovum IgM-like protein is unknown.

KEY WORDS: IgM . Immunoglobulin . Salmonids . Eggs

Published in DAO Vol. 23, No. 2 (1995) on October 26
ISSN: 0177-5103. Copyright © Inter-Research, Oldendorf/Luhe, 1995