Serendipitous discovery of a novel protostrongylid (Nematoda: Metastrongyloidea) in caribou, muskoxen, and moose from high latitudes of North America based on DNA sequence comparisons

Abstract

Fecal samples are often the only feasible means to assess diversity of parasites in wildlife; however, definitive identification of egg or larval stages in feces by morphology is rarely possible. We determined partial sequences from the second internal transcribed spacer region (ITS-2) of nuclear ribosomal DNA for first-stage, dorsal-spined larvae (DSL) in feces from caribou ( Rangifer tarandus tarandus (L., 1758), Rangifer tarandus caribou (Gmelin, 1788), Rangifer tarandus grantii (Allen, 1902)), muskoxen ( Ovibos moschatus moschatus (Zimmermann, 1780), Ovibos moschatus wardi Lydekker, 1900), moose ( Alces alces gigas Miller, 1899 and Alces alces andersoni Peterson, 1952), and from the tissue of one slug ( Deroceras laeve (Müller, 1774)) in Arctic–Subarctic North America. A previously uncharacterized, genetically distinct species was recognized based on sequences of 37 DSL from 19 ungulate hosts and the slug. Sequence similarity among individuals of this novel species was 91%–100%. For many individual DSL, paralogues of ITS-2 were detected. ITS-2 sequences from the novel species were 72%–77% similar to those of Varestrongylus alpenae (Dikmans, 1935) and 51%–61% similar to those of other protostrongylids known in North American and some Eurasian ungulates. Results indicate a discrete lineage of an undescribed protostrongylid infecting muskoxen, caribou, and moose from Alaska to Labrador. Sympatric infections with Parelaphostrongylus andersoni Prestwood, 1972 were found in three caribou herds.

Serum Biochemistry, Serology, and Parasitology of Boreal Caribou (Rangifer Tarandus Caribou ) in the Northwest Territories, Canada

“…Larvae of Parelaphostrongylus odocoilei, a muscle worm, have been identified in this population of boreal caribou (Jenkins et al, 2005). In addition, P. odocoilei has been isolated from boreal caribou in several locations in Alberta, and P. andersoni has been found in barrenground caribou in the Northwest Territories and in caribou in Labrador, suggesting that these parasites are widespread in woodland caribou of central and northcentral Canada (Gray and Samuel, 1986;Lankester and Hauta, 1989;Jenkins et al, 2005;Kutz et al, 2007). Although P. odocoilei is most likely responsible for the protostrongylid larvae seen in these caribou, concurrent or mixed infection cannot be ruled out without further molecular diagnostics.…”

“…Clinical disease associated with Toxoplasma gondii has not been reported in free-ranging caribou (Kutz et al, 2001); however, experimental infection of reindeer caused acute, severe, and fatal hemorrhagic enteritis (Oksanen et al, 1996), and fatal transplacental toxoplasmosis has been reported in a naturally infected reindeer (Dubey et al, 2002). Toxoplasma gondii poses a potential public health risk for humans handling or consuming raw meat from infected animals, and further study of definitive hosts for this parasite in northern ecosystems, as well as the host range, distribution, and intensity of infection in boreal caribou, is needed.…”

“…Protostrongylid nematodes cause recognized disease syndromes in ungulates and have been implicated in the declines in wildlife populations (Kutz et al, 2007). In North America, five genera of protostrongylids parasitize artiodactyls: Elaphostrongylus, Parelaphostrongylus, Muellerius, Umingmakstrongylus, and Varestrongylus (Jenkins et al, 2005;Kutz, et al, 2007), and all produce characteristic dorsalspined larvae.…”

“…In North America, five genera of protostrongylids parasitize artiodactyls: Elaphostrongylus, Parelaphostrongylus, Muellerius, Umingmakstrongylus, and Varestrongylus (Jenkins et al, 2005;Kutz, et al, 2007), and all produce characteristic dorsalspined larvae. Larvae of Parelaphostrongylus odocoilei, a muscle worm, have been identified in this population of boreal caribou (Jenkins et al, 2005).…”

Finding Them Before They Find Us: Informatics, Parasites, and Environments in Accelerating Climate Change

“…For example, the technique popularly known as genetic or DNA barcoding offers the possibility of performing nondestructive monitoring of hosts for parasites. This creates the potential to shift from logistically challenging field collections, necropsy, and morphological characterization based on assessments of a few hosts to more geographically extensive, siteintensive, and near-simultaneous sampling across ecosystems, thus linking landscape to regional scales for assemblages of host species and populations (e.g., Jenkins et al, 2005;Kutz et al, 2007). This means we now have or can develop the capacity to more readily assess parasite impacts on host species that are rare or endangered.…”