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Prompt and reliable diagnostic tests for taeniid infection in canids are important due to the risk of zoonoses like Echinococcus spp. Current diagnostic methods relying on fecal flotation lack sensitivity and specificity, but this has rarely been quantified due to the challenges in performing adult cestode recovery (the gold standard) in domestic dogs (Canis familiaris). Therefore, we recovered adult Taenia and Echinococcus spp. from intestines, as well as fecal/intestinal material from 484 wild canids trapped for fur in two Canadian provinces (276 foxes – primarily Vulpes vulpes, coyotes – Canis latrans, and wolves – Canis lupus in Quebec and 208 coyotes in Saskatchewan). The performances of a newly developed coproPCR for tapeworm DNA detection in dogs, and centrifugal fecal flotation using Sheather’s solution, were evaluated against adult cestode recovery. Overall, adult taeniid cestode prevalence (Taenia and/or Echinococcus) was 28 % (95 % CI: 23–33 %) in Quebec (62 % (CI: 51−73%) of 74 coyotes, 65 % (CI: 44−82) of 23 wolves, and 11 % (CI: 7−16%) of 179 foxes) and 79 % (CI: 73−84%) of 208 coyotes in Saskatchewan. In Quebec, E. canadensis and Taenia spp. were detected in coyotes and wolves, and foxes were only infected with Taenia spp., whereas Saskatchewan coyotes were predominantly infected with E. multilocularis (at significantly higher prevalence, but not intensity, than coyotes in Quebec). Compared with centrifugal fecal flotation, the new coproPCR had at least double the sensitivity (58 % vs 23 % in QC coyotes, 57 % vs 23 % in QC wolves, 24 % vs 0% in QC foxes, and 80 % vs 25 % in SK coyotes). Notably, no taeniid eggs were detected on flotations from foxes infected with Taenia spp., and the new coproPCR had highest sensitivity in Saskatchewan coyotes, which were predominantly infected with E. multilocularis. CoproPCR has promising prospects for use in Veterinary clinics and diagnostic laboratories to detect taeniid cestode infections because of its higher sensitivity than faecal flotation methods. This is particularly important for zoonotic Echinococcus spp. where, from a public health perspective, false negatives are a much greater concern than false positives.

Discretionary food choices (snacks) contribute up to a third of the daily energy intake and potentially contribute to energy imbalance and weight gain. Individual snack intake behaviour is guided by internal and external cues, with social cues (seeing others eat, being alone) consistently showing large effects. A wide body of (mainly laboratory-based) research suggests marked differences in people's response to eating cues based on BMI. Here, we show that these BMI differences in cue responsiveness also pertain to everyday snacking behaviour. In two combined ecological momentary assessment studies, 122 participants with BMIs ranging from 18.34 to 45.71 kg/m2 logged their everyday snacking behaviour in real-time over two weeks along with the presence or absence of social cues. Random-effects modelling showed that people with higher BMI were more likely to consume high-energy snacks when alone, and were more likely to consume low-energy snacks in the presence of others eating. This suggests BMI differences in cue responsiveness that are in line with impression management theory and underlines the importance of social cues for snacking behaviour and provides avenues for both theory and intervention development.

Zoonotic Echinococcus spp. cestodes (E. canadensis and E. multilocularis) infect domestic animals, wildlife, and people in regions of Canada and the USA. We recovered and quantified Echinococcus spp. cestodes from 22 of 307 intestinal tracts of wild canids (23 wolves, 100 coyotes, 184 red and arctic foxes) in the state of Maine and the province of Québec. We identified the species and genotypes of three Echinococcus spp. cestodes per infected animal by sequencing mitochondrial DNA at two loci. We further confirmed the absence of E. multilocularis by extracting DNA from pools of all cestodes from each animal and running a duplex PCR capable of distinguishing the two species. We detected E. canadensis (G8 and G10), but not E. multilocularis, which is emerging as an important human and animal health concern in adjacent regions. Prevalence and median intensity of E. canadensis was higher in wolves (35%, 460) than coyotes (14%, 358). This parasite has historically been absent in Atlantic regions of North America, where suitable intermediate hosts, but not wolves, are present. Our study suggests that coyotes are serving as sylvatic definitive hosts for E. canadensis in Atlantic regions, and this may facilitate eastward range expansion of E. canadensis in the USA and Canada. As well, compared to wolves, coyotes are more likely to contaminate urban green spaces and peri-urban environments with zoonotic parasites., Author summary Echinococcosis is a zoonosis caused by ingestion of tapeworm eggs in feces of wild or domestic canids (e.g. foxes, wolves, coyotes, and dogs). In North America, the number of new human echinococcosis cases reported annually is low; however, recent reports of these parasites in unusual presentations, in new locations, and in wildlife near urban areas have caused renewed interest by veterinary and human health professionals. In a cross-border collaboration, we examined the intestines of wolves (Canis lupus), coyotes (C. latrans) and foxes (Vulpes vulpes, V. lagopus) trapped in Québec (Canada) and neighboring Maine (USA), using genetic tools to identify Echinococcus tapeworms. We did not detect E. multilocularis, a serious threat to human health that has recently emerged in southern Ontario. We did identify E. canadensis in wolves and coyotes, in both Quebec and Maine. The presence of this parasite in coyotes is especially concerning because coyotes are more likely to come into close proximity with human communities. This information is relevant to veterinarians who should promote regular fecal examination and/or deworming of high risk dogs (dogs that scavenge or hunt cervids, such as moose), to physicians who might encounter this relatively rare disease, and to public health agencies who should promote surveillance and develop precautions for high risk people.