Intestinal establishment and reproduction of adult Trichinella spp. in single and mixed species infections in foxes (Vulpes vulpes)

Danish Centre for Experimental Parasitology, Department of Veterinary Pathobiology, Royal Veterinary and Agricultural University, Dyrlaegevej 100, DK-1870 Frederiksberg C, Denmark.
Veterinary Parasitology (Impact Factor: 2.46). 07/2005; 130(3-4):245-53. DOI: 10.1016/j.vetpar.2005.03.030
Source: PubMed


Intestinal establishment and reproduction of adult Trichinella spiralis, Trichinella nativa, Trichinella britovi and Trichinella pseudospiralis were examined as single species or mixed species infections in foxes. This is the first study of intestinal dynamics of Trichinella spp. in a carnivore model and the results suggest that the intestinal phase is relatively short as only very few worms were recovered 10 days post-inoculation (dpi). In mixed species infection with equal doses of T. nativa and T. spiralis, molecular typing demonstrated that 64% of the intestinal worms and 78% of the muscle larvae were T. nativa. Conversely, T. spiralis dominated in the mixed species infections with T. pseudospiralis, constituting 66% of the intestinal worms and 94% of the muscle larvae. Although, the individual recoveries of intestinal worms were only up to 5.6% on day 1, and up to 1.5% on day 4 post-infection, the muscle larvae establishment was comparable to other fox studies. Infectivity, measured as muscle larvae burden did not differ among the four species of Trichinella, which is in contrast to other models with mice, rats, pigs or herbivores. Although statistically significant differences in intestinal worm burdens were found for some days, no distinct species were recovered in consistently higher numbers than the others.

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    • "It is not known how long and at which levels antibodies persist after a bear was challenged by ingestion of food harbouring Trichinella ML, but antibody levels in experimentally infected foxes followed for approximately a year were unaltered (Møller et al., 2005a). Infection with two or more species of Trichinella is documented in wild boar (Nöckler et al., 2006) and foxes in Europe (Pozio et al., 1995; Malakauskas et al., 2007) including experimentally infected foxes (Webster and Kapel, 2005b). This suggests that infection may occur more than once during the life span of such animals (Pozio, 2005) or that simultaneous infection with more than one Trichinella species may be acquired. "
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