MILK BORNE IMMUNITY
A striking new example of mammary transmission of acquired specific immunity is reported by Berry and Slavin1 of the University of Rochester School of Medicine. The transfer of humoral antibodies from mother to young by the mammary route was first demonstrated by Ehrlich.2 Mice born of mothers immune to certain toxic proteins are highly resistant to the same toxins if nursed by their own mothers but are almost wholly nonresistant if foster nursed by nonimmune mothers. Vaillard3 confirmed these observations. He found that tetanus antitoxin administered after parturition to lactating mothers would confer an effective antitetanus immunity on breast fed young. Practical interest in milk borne immunity was increased by the later demonstration4 that in domestic cattle the apparently hereditary transmission of natural immunity to environmental saprophytes is dependent on an initial colostrum feeding, the subsequent milk being deficient in the necessary antibodies.