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
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.
Available from: Åsbakk Kjetil
- "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. "
[Show abstract] [Hide abstract]
ABSTRACT: Blood samples of live-caught polar bears (Ursus maritimus) from Svalbard collected 1991-2000 (Period 1) and 2006-2008 (Period 2) and from the pack ice of the Barents Sea collected in Period 1, were assayed for antibodies against Trichinella spp. by ELISA. Of 54 cubs-of-the-year included in the Period 1 sample, 53 were seronegative, indicating that exposure to Trichinella infected meat is uncommon during the first months of life for polar bears in the Svalbard region. Of 30 mother-offspring pairs, 18 mothers were seropositive with seronegative offspring (n=27), suggesting (1) that maternal antibodies had dropped to levels below detection limit by the time of capture in April (offspring approximately 4 months old), and (2) supporting experimental studies in other animal models showing that vertical transmission of Trichinella spp. is uncommon. Bear 1 year and older had higher prevalence in Svalbard (78%) than in the Barents Sea (51%). There was no temporal change in prevalence for bears from Svalbard during the time between the two periods. The prevalence increased with age in both sexes. A positive correlation was found between anti-Toxoplasma gondii and anti-Trichinella spp. antibodies.
Veterinary Parasitology 09/2010; 172(3-4):256-63. DOI:10.1016/j.vetpar.2010.05.018 · 2.46 Impact Factor
Available from: Hugo Razuri
[Show abstract] [Hide abstract]
ABSTRACT: Because of a lack of comprehensive surveys, the geographic distributions of the North American species of encapsulating Trichinella (T. nativa and its variant T6, T. murrelli, and T. spiralis) are poorly characterized in detail. These species are potentially zoonotic; therefore, biogeographic information is critical to monitoring their status and any distribution changes due to climatic and man-made environmental impacts. The maximum entropy (Maxent) program was used to model predicted ranges for these sylvatic Trichinella spp., using a limited number of available location records with confirmed species identifications collected over 55 yr throughout North America. The resulting prediction models were shown to be robust, and the species maps created are presented. The predicted range of T. nativa is primarily north of the 48 degrees - 52 degrees latitudes, overlapping the Tundra, sub-Arctic, and Warm Continental eco-regions. Its sympatric genotypic variant, T6, has a predicted range covering primarily the sub-Arctic and mountainous Temperate Steppe eco-regions, the latter extending below 48 degrees N latitude. In the east, the T6 range includes the Warm Continental and the mountainous Hot Continental eco-regions; the T6 range is also predicted to extend to the Sierra Madre Mountains of Mexico. The most probable range of T. murrelli is centered in the Midwest within the Hot Continental and Prairie eco-regions, with an extension southward to the Subtropical and Tropical/Subtropical Steppe and Desert eco-regions. In the west, it exists in a restricted range characterized as mountainous Mediterranean. The most probable distribution of sylvatic T. spiralis is along the humid east North American coast (Hot Continental south to Subtropical), and along the coast of northwest North America (Marine) to Alaska (subArctic and Tundra). Its most southerly range extends into central Mexico (Tropical/Subtropical Desert). The difference in relative freeze resistance between T. nativa/T6 and T. murrelli undoubtedly accounts for much of this geographic separation. However, the factors responsible for the absence of a more southerly distribution of T. nativa are not obvious, given the overlap in host range with T. murrelli. The maximum July temperature appears to have a significant effect on this distribution pattern. The results of the model building highlight subjects for future research on the biotic and abiotic factors important in determining Trichinella spp. distributions and directions for model validation research.
Journal of Parasitology 08/2009; 95(4):829-37. DOI:10.1645/GE-1952.1 · 1.23 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: Rats are selective hosts for Trichinella nativa; infection levels in their muscles remain low when compared to Trichinella spiralis. To identify in which phase of the life cycle the selective responses take place, rats were infected perorally (p.o.) and intravenously (i.v.) with T. spiralis and T. nativa. Six rats were placed in each group; three rats served as uninfected controls. The infection intensities were examined 5 or 6 weeks after the infection. T. spiralis muscle larva burden was 57 times higher compared to that of T. nativa after p.o. inoculation (mean larvae per gram ± SD, 1,243 ± 378.9 vs. 22 ± 21.5). In i.v. inoculation, 12 times more T. spiralis larvae reached the muscle than with T. nativa. Also, in vitro newborn larva (NBL) production at day 6 postinfection was analyzed for parasites originating from both rat and mouse. The mean number of in vitro-produced NBL of rat-origin T. spiralis during 24 h was 70 (95 % CI, 65-75) and of T. nativa, 23 (95 % CI, 21-24). Intriguingly, this difference was less obvious with mouse-origin female Trichinella. NBL production of mouse origin T. spiralis was 57 (95 % CI, 51-62) and T. nativa, 29 (95 % CI, 26-31). Intestine histology at day 40 post p.o. infection, serological response, and weight dynamics were indistinguishable between the Trichinella species but differed from controls. Our results show that the defense against T. nativa is not solely enteral in rats but may partly be explained by different reproduction processes for the two Trichinella species in rat.
Parasitology Research 08/2012; 111(6). DOI:10.1007/s00436-012-3080-x · 2.10 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.