Gastrointestinal helminths of wolves (Canis lupus Linnaeus, 1758) in Piedmont, north-western Italy

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.

Non-MHC immunity genes do not affect parasite load in European invasive populations of common raccoon

Understanding the evolutionary mechanisms behind invasion success enables predicting which alien species and populations are the most predisposed to become invasive. Parasites may mediate the success of biological invasions through their effect on host fitness. The evolution of increased competitive ability (EICA) hypothesis assumes that escape from parasites during the invasion process allows introduced species to decrease investment in immunity and allocate resources to dispersal and reproduction. Consequently, the selective pressure of parasites on host species in the invasive range should be relaxed. We used the case of the raccoon Procyon lotor invasion in Europe to investigate the effect of gastrointestinal pathogen pressure on non-MHC immune genetic diversity of newly established invasive populations. Despite distinct differences in parasite prevalence between analysed populations, we detected only marginal associations between two analysed SNPs and infection intensity. We argue that the differences in parasite prevalence are better explained by detected earlier associations with specific MHC-DRB alleles. While the escape from native parasites seems to allow decreased investment in overall immunity, which relaxes selective pressure imposed on immune genes, a wide range of MHC variants maintained in the invasive range may protect from newly encountered parasites.

Squamata reptiles as a potential source of helminth infections when preyed on by companion animals

BACKGROUND

Squamate reptiles cohabiting with companion animals may represent a source of helminth infections, especially through predation by dogs and cats with an outdoor lifestyle.

METHODS

In order to assess the role of reptiles as intermediate/paratenic hosts of trophically transmitted helminths, synanthropic reptiles (n = 245) captured from different ecological settings (i.e., households, dog shelters, urban, peri-urban and rural areas or natural parks) of southern Italy were examined for endoparasites. Parasitic cysts (i.e., larval forms of acanthocephalans, cestodes and nematodes) and free helminths (i.e., adult nematodes and digeneans) were morphologically and molecularly identified, and statistical analysis was carried out to evaluate the correlations between reptiles, infections, and ecological settings.

RESULTS

Overall, 31% of reptiles were positive for at least one helminth, with Podarcis siculus (18.7%) and Tarentola mauritanica (8.1%) being the most frequently infected species. Among the parasites of medical interest, Joyeuxiella echinorhyncoides showed the highest prevalence (19.7%), followed by Diplopylidium acanthotetra (10.5%), Joyeuxiella pasqualei, Mesocestoides lineatus (5.6%) and Physaloptera sp. (3.9%). Macracanthorhynchus hirudinaceus was detected once. Podarcis siculus and T. mauritanica were associated with cestode infections.

CONCLUSIONS

The wide range of helminths detected here in reptiles living in sympatry with pets and the fact that many of these helminth species are parasitic and may infect companion animals (e.g., J. pasqualei, J. echinorhyncoides, D. acanthotetra, Physaloptera sp.) and humans (i.e., Macracanthorhynchus hirudinaceus, Mesocestoides lineatus) indicate the potential health risk associated with pets preying on these small vertebrates. Our results indicate the need for complementary investigations of trophically transmitted parasites in dogs and cats living in sympatry with reptiles.

Wolf Dispersal Patterns in the Italian Alps and Implications for Wildlife Diseases Spreading

Simple Summary

Wildlife dispersal directly influences population expansion patterns, and may have indirect effects on the spread of wildlife diseases. For many species, little is known about dispersal, despite its importance to conservation. We documented the natural dispersal processes of an expanding wolf (Canis lupus) population in the Italian Alps to understand the dynamics of the recolonization pattern and identify diseases that might be connected with the process through the use of non-invasive genetic sampling over a 20-year period. By documenting 55 dispersal events, with an average minimum straight dispersal distance of 65.8 km (±67.7 km), from 7.7 km to 517.2 km, we discussed the potential implications for maintaining genetic diversity of the population and for wildlife diseases spreading.

Abstract

Wildlife dispersal directly influences population expansion patterns, and may have indirect effects on the spread of wildlife diseases. Despite its importance to conservation, little is known about dispersal for several species. Dispersal processes in expanding wolf (Canis lupus) populations in Europe is not well documented. Documenting the natural dispersal pattern of the expanding wolf population in the Alps might help understanding the overall population dynamics and identifying diseases that might be connected with the process. We documented 55 natural dispersal events of the expanding Italian wolf alpine population over a 20-year period through the use of non-invasive genetic sampling. We examined a 16-locus microsatellite DNA dataset of 2857 wolf samples mainly collected in the Western Alps. From this, we identified 915 individuals, recaptured 387 (42.3%) of individuals, documenting 55 dispersal events. On average, the minimum straight dispersal distance was 65.8 km (±67.7 km), from 7.7 km to 517.2 km. We discussed the potential implications for maintaining genetic diversity of the population and for wildlife diseases spreading.

Zoonotic intestinal helminthes diagnosed in a 6-year period (2015-2020) in privately owned dogs of sub-urban and urban areas of Italy

Intestinal helminthes of dogs have a relevant role for health and welfare of canine populations and many of them are zoonotic. Thus, a constant surveillance is pivotal to safeguard companion dogs and human health. Data from faecal examinations of pet dogs obtained in the last six years during the routine activity of the laboratory of Parasitology and Parasitic diseases of the University Teaching Veterinary Hospital of the University of Teramo, Italy, are here reported. From 2015 to 2020 a total of 1083 individual faecal samples from privately owned dogs were examined using conventional copro-microscopic techniques. Endoparasite elements were found in 278 (25.7%) dogs, and among them, eggs of intestinal zoonotic helminthes were detected in 184 (17%) samples. The most common zoonotic parasites were Toxocara canis and hookworms (8.9% positivity rate for both). Most dogs (88%) were positive for a single zoonotic parasite while 12% of the positive animals harbored two or more zoonotic helminthes. A statistical analysis showed a significant association between dogs with less than one year of age and positivity to at least one intestinal zoonotic helminth, and that infections by T. canis are significantly more prevalent in dogs under one year of age. Despite being well known in canine clinical practice, these results indicate that zoonotic helminthes are still frequent in owned dogs. Thus, increased awareness of veterinary practitioners and pet owners is necessary to implement current diagnostic and control strategies to minimize the risk of zoonotic transmission of intestinal helminthes.

First Parasitological Data on a Wild Grey Wolf in Turkey with Morphological and Molecular Confirmation of the Parasites

INTRODUCTION

The grey wolf (Canis lupus) is the natural host of many parasites. These animals travel quite long distances to search for prey and nests, causing parasites to spread over large areas; therefore, determination of the parasites carried by grey wolves is important.

METHODS

In this study, we used both morphological and molecular methods for parasitological identification of helminth species. For this purpose, the material obtained after necropsy was examined by macroscopic, microscopic, and molecular (multiplex PCR and DNA sequencing) methods.

RESULTS

No pathological lesions and parasites were detected in the macroscopic examination of the trachea, lungs, heart, liver, spleen, stomach, and kidneys. The parasites collected from the intestines and diaphragm muscles were identified as Taenia hydatigena, Mesocestoides litteratus and Trichinella britovi.

CONCLUSION

The aim of this study was to determine the helminth species in a dead grey wolf from wildlife. To the best of our knowledge, with this study, Taenia hydatigena, Mesocestoides litteratus and Trichinella britovi were detected for the first time in a grey wolf in Turkey.