SEROLOGICAL SURVEY OF SELECTED CANINE VIRAL PATHOGENS AND ZOONOSES INGRIZZLY BEARS (URSUS-ARCTOS HORRIBILIS) AND BLACK BEARS (URSUS-AMERICANUS) FROM ALASKA

Between 1988 and 1991, 644 serum samples were collected from 480 grizz ly bears (Ursus arctos horribilis) and 40 black bears (Ursus americanu s) from Alaska, United States of America, and were tested for selected canine viral infections and zoonoses. Antibody prevalence in grizzly bears was 0% for parvovirus, 8.3% (40/480) for distemper, 14% (68/480) for infectious hepatitis, 16.5% (79/480) for brucellosis, 19% (93/480 ) for tularaemia and 47% (225/478) for trichinellosis. In black bears, prevalence ranged from 0% for distemper and parvovirus to 27.5% for t richinellosis and 32% for tularaemia. Antibody prevalence for brucello sis (2.5%) and tularaemia (32%) were identical for grizzly bears and b lack bears from the geographical area of interior Alaska. Links betwee n differences in prevalence and the origin of the grizzly bears were o bserved. Antibodies to canine distemper virus and infectious hepatitis virus were mainly detected in grizzly bears from Kodiak Island and th e Alaskan Peninsula. Brucellosis antibodies were prevalent in grizzly bears from western and northern Alaska, whereas tularaemia antibodies were detected in grizzly bears from interior Alaska and the Arctic. Th ere was a strong gradient for antibodies to Trichinella spp. from sout hern to northern Alaska. For most diseases, antibody prevalence increa sed with age. However, for several infections, no antibodies were dete cted in grizzly bears aged from 0 to 2 years, in contrast to the prese nce of those infections in black bears. Grizzly bears served as excell ent sentinels for surveillance of zoonotic infections in wildlife in A laska.