Lymphatic dwelling filarioid nematodes in reindeer Rangifer tarandus tarandus, (Cervidae) in Finland, identified as Rumenfilaria andersoni Lankester & Snider, 1982 (Nematoda: Onchocercidae: Splendidofilariinae)

• Main Authors: Laaksonen S., Saari S., Nikander S., Oksanen A., Bain O.
• Format: Article
• Language: English
• Published: EDP Sciences 2010-03-01
• Series: Parasite
• Subjects: filarioid; lymphatic filariosis; Rumenfilaria; Rangifer tarandus; Alces alces
• Online Access: http://dx.doi.org/10.1051/parasite/2010171023

A filarioid nematode inhabiting the lymphatic vessels of the subserosal rumen and mesenteries associated with a high prevalence of its microfilariae in peripheral blood was observed in Finnish reindeer (Rangifer tarandus tarandus) in 2004 and 2006. Adult specimens were collected by dissecting lymphatic vessels from slaughtered animals, where some of the nematodes were seen through the wall of the dilated vessels as thin white winding threads obscuring the vessel. The morphology of adult worms and microfilaria is described based on light and scanning electron microscopy. These filariae belong to the subfamily Splendidofilariinae of the Onchocercidae and resemble Rumenfilaria andersoni, recovered from different host and localization, the ruminal veins of Alces alces in Canada. Comparison of paratypes of this species revealed only minor differences which were not sufficient to separate the filarioid parasitic in R. tarandus in Finland and we identify the nematode as R. andersoni. However, the findings suggest two different parasite populations. The finalizing of this taxonomic question in the future requires an integrated approach, in which the DNAbased and morphological identifications are consistent.