Parasites of wolves, Canis lypus L., in northeastern Minnesota, as indicated by analysis of fecal samples

A walk on the wild side: A review of the epidemiology of Toxocara canis and Toxocara cati in wild hosts

Toxocara species are cosmopolitan nematode parasites of companion, domestic and wild hosts. Of the 26 known species of Toxocara, only Toxocara canis and Toxocara cati are definitively zoonotic. The significance of wild carnivores as definitive hosts of T. canis and T. cati respectively, has received far less attention compared to domestic dogs and cats. Complex environmental changes have promoted increasing contact between wildlife, domestic animals and humans that can enhance the risk of pathogen spillover. This review lists a total of 19 species of wild canid host that have been shown to act as definitive hosts for T. canis and a total of 21 species of wild felid host. In general, the number of publications focusing on felid host species is fewer in number, reflecting the general paucity of data on T. cati. The wild canids that have received the most attention in the published literature include the red fox (Vulpes vulpes), the wolf (Canis lupus), and the golden jackal (Canis aureus). The wild felid species that has received the most attention in the published literature is the Eurasian lynx (Lynx lynx). Some non-canid and non-felid hosts also act as definitive hosts of Toxocara species. Certainly, red foxes would appear to be the most significant wild species in terms of their potential to transmit Toxocara to domestic dogs and humans via environmental contamination. This can be explained by their increasing population densities, encroachment into urban areas and their dietary preferences for a wide range of potential paratenic hosts. However, a major challenge remains to assess the relative importance of wild hosts as contributors to environmental contamination with Toxocara ova. Furthermore, one major constraint to our understanding of the significance of wildlife parasitism is a lack of access to samples, particularly from rare host species.

Parasite survey on a captive wolf population using classical techniques and ELISA coproantigen detection, USA

As laws change around the United States, wildlife that were once kept as companion animals are now often confiscated by local authorities. They are then euthanized unless a home is found for them at a sanctuary. Wolf sanctuaries are, therefore, becoming increasingly important for their conservation and management. However, little data is available on best practices for the health management of captive wolves, including data on parasitic diseases. Our objective was to assess the prevalence of parasites of captive wolves combining classical coprological techniques and immunoassays based on the detection of coproantigen of selected canid parasites. Fecal samples of 39 animals were collected upon observation of individual animals defecating. All samples were processed using the Fecal Dx® tests, a suite of coproantigen ELISAs for detection of ascarid, hookworm, whipworm, and Giardia (IDEXX Laboratories Inc.). Out of the 39 samples, 38 were processed using the double-centrifugation sugar flotation (DCSF) and 34 using a modification of the Baermann technique. Twenty-eight samples (71.8%) were positive for hookworm, and none positive for the other parasites tested using coproantigen ELISA. Ancylostoma sp. (26, 68.4%), Eucoleus boehmi (13, 34.2%), and Trichuris sp. (2; 5.3%), and Sarcocystis sp. (13, 34.2%) were detected using DCSF. No metastrongyloid lungworm larvae were found. The Cohen's kappa index (0.97) showed excellent agreement between the hookworm coproantigen ELISA and the DCSF using feces preserved in ethanol for a short period of time. This study provides a baseline on the parasites of captive wolves, and shows that recent innovative diagnostics in veterinary parasitology, developed and optimized for dogs, may be used for assessing the health of wolves.

How mammals stay healthy in nature: the evolution of behaviours to avoid parasites and pathogens

Mammals live and thrive in environments presenting ongoing threats from parasites in the form of biting flies, ticks and intestinal worms and from pathogens as wound contaminants and agents of infectious disease. Several strategies have evolved that enable animals to deal with parasites and pathogens, including eliminating away from the sleeping-resting areas, use of an array of grooming techniques, use of saliva in licking, and consuming medicinal plant-based compounds. These strategies all are species-specific and reflect the particular environment that the animal inhabits.This article is part of the Theo Murphy meeting issue 'Evolution of pathogen and parasite avoidance behaviours'.

The paradox of canine conspecific coprophagy

Canine conspecific coprophagy, the tendency or predisposition of some dogs to eat their own faeces or those of other dogs, seems paradoxical because dogs typically show an aversion to conspecific faeces. In an attempt to resolve this paradox, we set out to determine the factors associated with the occurrence of this behaviour and to evaluate the efficacy of 11 products marketed for treating coprophagy as well as behaviour modification procedures. Because a large sample of dogs was needed to address these issues, two web-based surveys were utilized. One, intended to compare coprophagic dogs and non-coprophagic dogs, yielded 1552 returns. The other, yielding 1475 usable returns, specifically recruited owners of coprophagic dogs to gather information about the characteristics of coprophagy and treatment success. The findings revealed that 16% of dogs sampled engaged in frequent conspecific coprophagy, defined as having been seen eating stools at least six times. No evidence was found relating the coprophagy to diet or the dog's age. Coprophagic dogs were as easily house trained as non-coprophagic dogs, suggesting a normal aversion to faeces. Coprophagic dogs were more likely to be reported as greedy eaters than non-coprophagic dogs. The reported success rate of the commercial products and behaviour modification approaches was close to zero, indicating that the behaviour is not readily changed. The coprophagy was overwhelmingly directed at fresh stools, defined as being no more than 2 days old. A hypothesis is offered that coprophagy reflects a tendency inherited from the ancestral wolf to keep the den area free of faecal-borne intestinal parasites that might be deposited in the den resting area and would typically have parasite ova that are not initially infective, but could develop infective larvae after 2 days. An evolved parasite defence strategy to consume fresh faeces in the rest area would be adaptive.

Alternative prey use affects helminth parasite infections in grey wolves

Predators affect prey populations not only through direct predation, but also by acting as definitive hosts for their parasites and completing parasite life cycles. Understanding the affects of parasitism on prey population dynamics requires knowing how their predators' parasite community is affected by diet and prey availability. Ungulates, such as moose (Alces americanus) and white-tailed deer (Odocoileus virginianus), are often important prey for wolves (Canis lupus), but wolves also consume a variety of alternative prey, including beaver (Castor canadensis) and snowshoe hare (Lepus americanus). The use of alternative prey, which may host different or fewer parasites than ungulates, could potentially reduce overall abundance of ungulate parasites within the ecosystem, benefiting both wolves and ungulate hosts. We examined parasites in wolf carcasses from eastern Manitoba and estimated wolf diet using stable isotope analysis. Taeniidae cestodes were present in most wolves (75%), reflecting a diet primarily comprised of ungulates, but nematodes were unexpectedly rare. Cestode abundance was negatively related to the wolf's δ(13) C value, indicating diet affects parasite abundance. Wolves that consumed a higher proportion of beaver and caribou (Rangifer tarandus), estimated using Bayesian mixing models, had lower cestode abundance, suggesting the use of these alternative prey can reduce parasite loads. Long-term consumption of beavers may lower the abundance of adult parasites in wolves, eventually lowering parasite density in the region and ultimately benefiting ungulates that serve as intermediate hosts. Thus, alternative prey can affect both predator-prey and host-parasite interactions and potentially affect food web dynamics.

Gastrointestinal parasites of coyotes (Canis latrans) in the metropolitan area of Calgary, Alberta, Canada

Disease ecology is a relevant but relatively unexplored subject of research in urban coyotes ( Canis latrans Say, 1823). In fact, this carnivore may play a role in the circulation of parasites that can have implications on the health of humans and domestic dogs, but can also be affected by pathogens transmitted from domestic reservoirs. To investigate the gastrointestinal parasites of urban coyotes in Calgary, Alberta, Canada, we analyzed 61 carcasses and 247 fecal samples collected within the metropolitan area, including city parks, in 2009–2010. We found nine parasite taxa: Toxascaris leonina (Linstow, 1902), Uncinaria stenocephala (Railliet, 1884), Ancylostoma caninum (Ercolani, 1859), Pterygodermatites affinis (Jägerskiöld, 1904), Trichuris vulpis (Froelich, 1789), Echinococcus multilocularis Leuckart, 1863, Taenia crassiceps (Zeder, 1800), genus Giardia Kunstler, 1882, and genus Cystoisospora Frenkel, 1977. Factors related to coyote ecology, habitat characteristics, and dog management likely influence the community of coyote parasites in an urban environment, and need to be taken into account to assess the actual role of this carnivore in the maintenance of parasites in the city landscape. Further research is needed to assess the current risk for transmission of potentially zoonotic parasites (e.g., E. multilocularis, T. crassiceps, Giardia sp.) among coyotes, dogs, and humans.

A faecal analysis of helminth infections in wild and captive wolves, Canis lupus L., in Poland

One hundred and three samples of faeces of reared grey wolves from four locations (Stobnica Park and Zoological Gardens in Bydgoszcz, Wrocław and Cracow) and twenty-six samples of faeces from two free-roaming packs of grey wolf (Canis lupus L.) in Piła (Forest Divisions: Borne Sulinowo, Czarnobór, Jastrowo) and Zielona Góra (Forest Divisions: Torzym, Krosno Odrzańskie) were collected between 2005 and 2007. Helminth eggs were detected in 78.6% of faecal samples of reared grey wolves and in 88.4% of those of free-roaming wolves. The trematode Alaria alata (80.1%) and nematodes Eucoleus aerophilus (23.1%) and Spirocerca lupi (11.5%) were only detected from wild packs of wolves and the nematodes Ancylostoma caninum (35.9%), Trichuris vulpis (15.5%) and Toxocara canis (3.9%) were only detected from reared wolves. Differences were observed in the prevalence and composition of helminth fauna between reared and wild grey wolves and our results are compared with those from studies within Poland and elsewhere in Europe.