NEONATAL ISOERYTHROLYSIS IN MULE FUELS

Four mule foals received anti-RBC antibody from their dam's colostrum. Two foals developed anemia, 1 developed severe thrombocytopenia, and 1 did not develop any clinical or laboratory abnormalities. All foals had the same donkey sire. Seven mares, including the dams of foals 1 t o 4, bred to the donkey sire produced anti-RBC antibody. Two mares pro duced anti-RBC antibody to the donkey RBC on the first mating. The don key sire and 18 of its offspring were found to have an RBC antigen uni que to mules and donkeys. Thus, all matings of this donkey to horse ma res were incompatible. The reason for the high rate of sensitization o f mares bred to this donkey is unknown.-J. L. Traub-Dargatz et al (J A m Vet Med Assoc 1995;206:67-70).