CANINE ANTISERUMS ANALOGOUS TO HUMAN ALLERGIC AND "BLOCKING" ANTISERUMS.

The serums of dogs that are allergic to ragweeed can passively sensitize normal dogs. Cutaneous reactions or systemic anaphylaxis may be produced by appropriate challenge with ragweed extract. Canine antiserum produced by immunization of normal dogs with ragweed extract is shown to inhibit these reactions of the passively sensitized dogs.