Frequencies of feline blood groups in the United States

A survey of AB blood group frequencies among cats in the United States was undertaken, using feline blood typing reagents from Australia. We typed blood of 280 cats of both genders and various breeds within the Philadelphia area and 205 cats at 27 veterinary medical teaching hospitals (most cats had been used as blood donors in 1987) throughout the United States. All but 2 cats had type-A blood. A Himalayan cat in Philadelphia and a domestic shorthair cat from Florida, neither of which had been used as a blood donor, had type-B blood. Plasma of the 2 blood-group-Bcats contained strong isoagglutinins (greater than 1:8 titer) against type-A cells, thereby allowing their detection in a major cross-match test. Approximately 30% of tested plasma samples from blood-group-A cats had weak isoagglutinins (1:2 titer) against type-B cells. This limited survey suggests that cats in the United States, including blood donors, predominantly have type-A blood, and that blood-group-B cats are rare.