Host and geographic differences in prevalence and diversity of gastrointestinal helminths of foxes (), coyotes () and wolves () in Québec, Canada.

Wild canids are hosts to a wide range of parasites and can play a role in transmission of zoonoses. As many parasites are transmitted through food webs, and wild canids are at high trophic levels, parasite prevalence and diversity in wild canids can serve as excellent indicators of ecosystem health. Our main objectives were to update knowledge on the composition of gastrointestinal helminths in wild canids from Québec, Canada, and to describe differences in parasite prevalence and diversity among canid species and regions. Hunters and trappers provided whole carcasses of red foxes () (N = 176), and intestinal tracts of coyotes () (N = 77) and gray wolves () (N = 23) harvested for non-research purposes over the winter of 2016-2017. A modified Stoll's centrifugation sucrose flotation on feces of 250 wild canids was used, and eggs of one family and eight genera of parasitic helminths were recovered: diphyllobothriids, spp., spp sp., sp., sp., sp., and sp. Adult spp. cestodes were recovered from 61 of 276 (22%) canids. Six different species (, , , , and -"like") were differentiated based on DNA sequenced from 65 individual adult cestodes using primers for the nicotinamide adenosine dinucleotide dehydrogenase subunit 1 (ND1) and cytochrome oxidase subunit 1 (CO1) mitochondrial DNA loci. sp. trematodes infected 89 of 276 canids (32%). A subset were identified as at the CO1 locus. The marine trematode was reported for the first time in foxes in the province of Québec. These results help us understand more fully the predator-prey relationships within this group of canids. This baseline data in regional parasite prevalence and intensity is critical in order to detect future changes following ecological disturbances due to climate and landscape alterations.