The transfer of immunity to the new-born calf from colostrum.

Some years ago, Theobald Smith and his associates (1) showed that passive immunity acquired by the new-born calf from colostrum is of prime importance in protection against infectious disease. At about the same time, Orcutt and Howe (2) observed that, after the ingestion of colostrum, agglutinins appear in the calf serum associated with a globulin which is precipitable at low concentrations of sodium sulfate. Jameson, AlvarezTostado, and Sortor (3) later found by electrophoretic analysis that the serum of the new-born calf does not contain -y-globulin, and that the appearance of slow moving globulin follows the feeding of colostrum. Similar observations have been made by San Clemente and Huddleson (4) for the calf, and by Polson (5) for the new-born foal. Since it has already been demonstrated that the immune lactoglobulin of the colostrum differs from the y-globulin of cow serum in electrophoretic mobility and ot,her properties (6-ll), it was of interest to ascertain whether the new protein which appears in calf serum after it receives colostrum possesses the same electrophoretic properties as the colostrum globulin, or whether this immune lactoglobulin is modified during its passage from the intestine of the calf to the blood stream. Hyperimmunization was performed with a mixture of antigens: diphtheria toxin (or toxoid), vaccinia virus, and a killed culture of Hemophilus pertussis.l It was, therefore, possible to follow changes in the acquired immunity of the calf parallel with electrophoretic studies of the serum, and to determine the duration of’the passively acquired immunity. A few observations have also been made on the electrophoretic patterns of the serum of the new-born lamb before and after the ingestion of colostrum, and these have been compared with the pattern obtained with maternal sheep serum.