Experimental infection with T. canis and T. leonina in farm mink (Neovison vison)

Abstract

Introduction: Farm mink (Neovison vison) can be naturally exposed to T. canis and T. leonina pathogens on the farm. If mink were hosts, it would imply some veterinary public health as well as animal welfare issues. For this reason, the aim of the study was to determine whether mink might be definitive or paratenic hosts of these parasites. Material and Methods: Four groups of mink were infected with both parasite species using larvated eggs or feed containing mouse tissue previously infected with the parasites. Following inoculation, the infections were monitored in vivo by faecal examination for 14 weeks p.i., and then western blotting and ELISA were performed. Results: Coprology did not reveal any canine roundworm eggs, neither were nematodes found in mink intestines during post mortem examination. The specific IgG antibodies recognising excretory/secretory (ES) antigens of both parasite species were identified in mink sera. Single T. leonina tissue larvae were found in digested organs. Conclusions: Our results confirm that farm mink may contribute both T. canis and T. leonina infections. It was proved that farm mink were not their definitive hosts, and therefore mink faeces need not be considered a source of canine roundworm eggs in any soil it fertilises. Nonetheless, as farm mink may be a paratenic host for both parasite species, this may have some impact on the health and welfare of infected animals.

Seroprevalence of Echinococcus spp. and Toxocara spp. in Invasive Non-native American Mink

“…Serological methods offer a sensitive and relatively specific alternative to necropsies or digestion methods. The usefulness of both ELISA and Western blot was confirmed, for example, in T. canis and T. leonina diagnoses in experimentally infected paratenic hosts (Klockiewicz et al 2019a). No false-posi-tive/false-negative results were stated in this study.…”

“…In this study, tissue larvae were found in experimentally infected farm American mink; histopathological examinations of parenchymal organs and striated muscles revealed lesions resembling those observed in other paratenic hosts due to toxocarosis (Klockiewicz et al 2019b). In addition, this infection was irrevocably confirmed by both ELISA and Western blot (Klockiewicz et al 2019a). Several up-to-date parasitological studies of American mink have been conducted in Belarus (Shimalov and Shimalov 2001a), Spain (Torres et al 2003), France (Torres et al 2008), andPoland (Kołodziej-Sobociń ska et al 2018), but neither adult Toxocara spp.…”

“…The second studied parasite, Toxocara spp., can infect a wide range of companion, domestic, and wild animals as both definitive and paratenic hosts via multiple routes of transmission, producing long-lived, tissue-inhabiting larvae and resistant eggs that can survive in the external environment (Holland 2017). A recent experimental study by Klockiewicz et al (2019a) revealed that American mink may be paratenic hosts for T. canis and T. leonina. In this study, tissue larvae were found in experimentally infected farm American mink; histopathological examinations of parenchymal organs and striated muscles revealed lesions resembling those observed in other paratenic hosts due to toxocarosis (Klockiewicz et al 2019b).…”

“…Used on rodent hosts, these methods deduced a 14.2% T. canis seroprevalence and showed ELISA to be more sensitive than PCR for detecting infection with the parasite (Krucken et al 2017). Studies using immunodiagnostic methods have been carried out worldwide (Krucken et al 2017;Li et al 2017;Lassen et al 2016;Klockiewicz et al 2019a). Serological analysis also allows the easy detection of mixed infections in hosts.…”

“…In addition, the sole published experimental study found that after oral inoculation with Echinococcus multilocularis protoscoleces, no adult tapeworms were recovered from American mink intestines, and the authors concluded that American mink cannot serve as a definitive host for E. multilocularis (Ooi et al 1992). Moreover, a recent experimental study done on farm American mink confirmed that this species may serve as a paratenic host for Toxocara canis and Toxascaris leonina (Klockiewicz et al 2019a). Thus, American mink should be further investigated to receive more data about their involvement in maintaining zoonotic parasites in the environment, though it can be assumed that this species serves as a paratenic host for both parasites.…”