[Increase of infection of European bison by nematodes Setaria labiatopapillosa in Białowie a Forest].

BACKGROUND

The aim of these studies was to determine the level of infection of European bison by nematodes belonging to the genus Setaria.

METHODS

From February 2006 to February 2007 21 bisons from 6 months to 20 years old shot in Białowieza Forest have been examined. During the necropsy pleural and peritoneal cavities were macroscopically examined for the presence of nematodes. The parasites were removed from tissues and fixed in 70% ethanol with 5% addition of glycerol and then identified to the species. Samples of blood were taken from shot bison and after centrifugation in microhaematocrit tubes directly examined to confirm the infection.

RESULTS

Nematodes Setaria labiatopapillosa were found in 71% of examined bisons. They usually laid freely in peritoneal cavity and sometimes also in pleural one. Accidentally single nematodes were observed in omentum on the surface of omasus and on the surface of liver surrounded by connective tissue. Intensity of bison infection by S. labiatopapillosa varied from 1 up to 24 specimens. Both young and old animals were infected with these nematodes. Observed after 3 years period over 30% rise of prevalence of nematodes S. labiatopapillosa, occurrence of these nematodes in all age groups of this host, and high intensity of infection are alarming. Although these nematodes in their typical localization and low level of infection do not evoke visible symptoms, the pathogenity of this species of nematode is not yet sufficiently recognized, and it is the reason, that monitoring of this infection in bison is necessary.