Presumptive neonatal isoerythrolysis in cats.

Entire or partial litters of 4 queens died due to hemolytic anemia within 1 to 2 days of birth. Necropsy and histologic examination of tissues from 6 dead kittens were indicative of neonatal isoerythrolysis. Blood samples from affected kittens were not available for study. Nevertheless, hemolysins and agglutinins in each queen's serum reacted with RBC from 2 sires of the affected litters. These antibodies, identified as anti-A, also reacted with the RBC from 64 random-source cats.