Heartworm, Acanthocheilonema spirocauda (Leidy, 1858), infections in Canadian phocid seals

• Published in: Canadian Journal of Fisheries and Aquatic Sciences
• Main Authors: Measures, L N, Gosselin, J -F, Bergeron, E
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1997
• Subjects: Aquatic Science; Ecology, Evolution, Behavior and Systematics; Arctic; Cystophora cristata; Erignathus barbatus; Harp Seal; hooded seal; Phoca groenlandica; Phoca hispida; Phoca vitulina; ringed seal
• Online Access: http://dx.doi.org/10.1139/f96-342; http://www.nrcresearchpress.com/doi/pdf/10.1139/f96-342

Heartworm, Acanthocheilonema spirocauda, was observed in four of six species of seals (19 seals of 701) examined from the Atlantic coast of Canada including the Canadian Arctic. Fourteen of 221 ringed seals (Phoca hispida), 2 of 18 harbour seals (Phoca vitulina), 2 of 186 harp seals (Phoca groenlandica) (new host record), and the only hooded seal examined (Cystophora cristata) were infected with A. spirocauda. Intensity of infection ranged from 1 to 31. Infected seals were age 0 to 14, but 8 of the 14 infected ringed seals were age 0. All worms were found in the right ventricle except in three cases. In one ringed seal and one harp seal, worms were found in the pulmonary artery, and in another ringed seal, worms were found deep within the lungs. No infections were found in grey seals (Halichoerus grypus) (N = 271) or bearded seals (Erignathus barbatus) (N = 4). Heartworm is primarily a parasite of young seals. Its apparent absence in grey seals examined to date suggests either that a much larger sample of young seals from a broad geographic area is needed or that grey seals are refractory to infection or do not survive infections.