Summary

Besnoitia tarandi is a protozoan parasite known to occur in caribou and reindeer. It is believed that this parasite has a two-host life cycle of which caribou are the intermediate host. Carnivores and biting arthropods have been respectively suggested as potential definitive hosts and vectors of besnoitiosis.

Typical lesions caused by B. tarandi in caribou include hair loss with irregular areas of thickened and crusty skin. Skin ulcers can also be present, especially on the scrotal sac. Parasitic cysts, approximately 0.5 mm in diameter, can be observed on the sclera and in the subcutaneous tissues, especially on the limbs. Numerous protozoan organisms with a typical morphology can be detected by histopathological examination in different tissues such as skin, testes and lungs.

This project takes advantage of CARMA-IPY field collections across a number of herds, to determine present prevalance and intensity of besnoitiosis in North America caribou herds.

 All data has been analyzed and papers are in progress.

 See Reports tab for links to poster and MSc thesis.

Results

In the Leaf River Herd, preliminary results suggest a prevalence of B. tarandi in 89% of animals targeted (n=9) due to their poor general condition when compared to a prevalence of 28% in samples randomly collected (n=53) and those obtained from hunters for the years 2007-2008.

In the George River Herd, preliminary results (n= 57) suggest a prevalence of B. tarandi of 15.8% in randomly collected caribou and those obtained from hunters for the years 2007-2008.

In the Bluenose West Herd, preliminary results suggest a prevalence of B. tarandi of 59 % (n=17) in randomly collected caribou and those obtained from hunters for the years 2007-2008.

In the Bathurst Herd, preliminary results suggest a prevalence of B. tarandi of 40 % (n=89) in randomly collected caribou and those obtained from hunters for the years 2007-2008.

In the Southampton Herd, preliminary results suggest a prevalence of B. tarandi of 12 % (n=17) in randomly collected caribou and those obtained from hunters for the years 2007-2008.

B. tarandi was not detected in the 46 examined samples taken from the Akia-Maniitsoq herd in Greenland.

Results also suggest that factors influencing prevalence might be the season, the gender, the age and the geographical location. These preliminary results will be evaluated in the comprehensive epidemiologic analysis

Applications

B. tarandi is commonly encountered in caribou, but the occurrence and the intensity of infection varies among herds. The scope of this project is to collect baseline information about this disease and to better understand its ecology. Impact of this parasite on the dynamic of the caribou population is still unclear but long term monitoring of this disease will help understand if this parasite is important determinant in the fluctuation of these populations over time.

Reports

Prevalence and intensity of Besnoitia in caribou.pdf

Écologie de la besnoitiose chez les populations de caribous (Rangifer tarandus) des régions subarctiques. 2011. MSc Thesis. Université de Montréal. Click here for library citation (and English abstract). Click here for full PDF version.

Contacts

Julie Ducrocq
Centre québécois sur la santé des animaux sauvages
Canadian Cooperative Wildlife Health Centre.
Faculté de médecine vétérinaire,
Université de Montréal,
St. Hyacinthe, Québec, Canada.
julie.ducrocq 'at' umontreal.ca

Stephane Lair
Centre québécois sur la santé des animaux sauvages
Canadian Cooperative Wildlife Health Centre.
Faculté de médecine vétérinaire,
Université de Montréal,
St. Hyacinthe, Québec, Canada.
(450) 773-8521 ext. 18667
stephane.lair 'at' umontreal.ca

Susan Kutz
Faculty of Veterinary Medicine,
University of Calgary,
Calgary, Alberta, Canada.
(403) 210-3824
skutz 'at' ucalgary.ca