Erythrocyte Antibodies as a Cause of Abortion in Cattle

Abstract

IT is well established that bacterial antibody does not cross the bovine placenta, and that although bacterial antigens can leave the non-pregnant uterus and enter the blood stream¹, it is unlikely that they would normally leave the pregnant uterus. The barrier to antibody and antigen transfer is generally ascribed to the effect of the multi-layered epithelio-chorial placenta of the bovine and the large size of the molecules concerned. Because of this it has been generally thought that haemolytic disease of the foetus was unlikely to occur in cattle; but hsemolytic disease of the new-born might follow sensitization of red blood corpuscles, by colostral antibody as it does in the mare^2,3. Although in cattle hæemolytic disease has not been recognized, there are a number of conditions of the fœtus such as some forms of early abortion, macerated foetus, hydrops foetalis, and premature still-birth, which have not been explained on other pathological grounds and which show certain features not altogether dissimilar to human hæmolytic disease. Normal agglutinogens comparable to the ABO groups of humans are believed to occur only rarely in cattle⁴; but a very large number of erythrocyte antigens have been defined by the production of immune sera in cattle and rabbits⁵.