Variation in prevalence and intensity of macroparasites in moose and their interactions with winter tick load in eastern Canada

Wild animals are infected with a large diversity and abundance of parasites that can affect their behavior, growth, body condition, and ultimately their survival. Although the adverse effects of parasites and the mechanisms involved in the interactions between a host and its parasites are generally well studied, much less is known about the additive or synergistic effects of multiple parasite species on a host. Moose populations in eastern Canada are infected by several species of endoparasites. In the last decades, the intensity of infestations by winter ticks, an ectoparasite, on moose have increased as a result of increased moose densities and favorable weather conditions that benefit winter tick survival. We aimed to document the diversity, intensity, prevalence, and distribution of different parasite species of moose in southern Quebec, Canada. We then evaluated the potential interaction between winter tick and endoparasites of moose, and we evaluated the effect of the simultaneous..., We conducted winter tick counts on the carcasses of moose harvested during the sport hunting season between 5 September and 19 November 2019 (n = 174) among 8 regions in Quebec (Canada). We estimated the number of winter tick per moose by counting tick larvae just after harvesting on three body parts (shoulder, wither, and buttock on one side of the animal) along four 10 cm vertical transects spaced 2 cm apart on each body part (total of 12 transects) (Sine et al. 2009). We used the total number of D. albipictus counted along the 12 transects as an indicator of moose winter tick load for statistical analyses.
We collected the heart (n = 99), lungs (n = 126), brain (n = 95), liver (n = 114), and distal intestine (n = 97) of hunted moose whenever possible and kept them frozen until laboratory analyses. We cut all the organs collected into one-centimeter-thick slices. Each slice was observed in the laboratory to identify and count all macroparasites present in each organ. We isolated piece..., , # Variation in prevalence and intensity of macroparasites in moose and their interactions with winter tick load in eastern Canada

[https://doi.org/10.5061/dryad.08kprr58f](https://doi.org/10.5061/dryad.08kprr58f)

We aimed to document the diversity, intensity, prevalence, and distribution of different parasite species of moose in southern Quebec, Canada. We then evaluated the potential interaction between winter tick and endoparasites of moose, and we evaluated the effect of the simultaneous presence of ticks and endoparasites on moose body condition. To do so, we collected organs to identify and count endoparasite species, estimate winter tick abundance, and measure subcutaneous fat thickness from 174 hunted moose in fall 2019 in 8 regions of Quebec. Our results showed that the prevalence and intensity of winter tick and gastrointestinal parasites differed among regions, as well as the prevalence of the heart parasite Taenia krabbei and the intensity of lung parasite Echinoccocus gran...