Prevalence of Trichinella infection in three sympatric large carnivores: effects of the host's sex and age

• Published in: Journal of Zoology
• Main Authors: Kojola, I., Holmala, K., Huhta, E., Oksanen, A., Kokko, S.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2016
• Subjects: Animal Science and Zoology; Ecology, Evolution, Behavior and Systematics; Canis lupus; Ursus arctos; Lynx; Lynx lynx lynx
• Online Access: http://dx.doi.org/10.1111/jzo.12394; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fjzo.12394; https://onlinelibrary.wiley.com/doi/pdf/10.1111/jzo.12394; https://onlinelibrary.wiley.com/doi/full-xml/10.1111/jzo.12394; https://zslpublications.onlinelibrary.wiley.com/doi/pdf/10.1111/jzo.12394

Abstract It has been suggested that the higher parasite prevalence for mammalian males might be due to differences in diet between the sexes or a lower immunocompetence of males. We examined how the prevalence of a large intracellular parasite, Trichinella spp., varies by sex and age in the brown bear Ursus arctos , grey wolf Canis lupus and Eurasian lynx Lynx lynx in Finland. Data were obtained from 801 bears, 312 wolves and 1958 lynxes killed during licensed hunting in autumn and winter. In all species, the prevalence was higher in males than females and was highest in adults. In bears and lynxes, the difference between the two sexes increased with age. In the brown bear, almost exclusively adults were infected by Trichinella , and prevalence was three times more frequent in adult males than females. In the wolf, prevalence in males was higher in all age classes, but in lynxes <1‐year‐old the prevalence did not differ with sex. According to our macroscopic stomach analysis, raccoon dog Nyctereutes procyonoides and red fox Vulpes vulpes , major reservoirs for Trichinella , were uncommon winter prey for lynx and wolves, but raccoon dogs were more frequently consumed by male than female lynxes. We suggest that differences in feeding habits between sexes might explain higher prevalence in males (at least in lynx and brown bear), though we could not exclude lower the immunocompetence.