Personne : Simard, Manon
En cours de chargement...
Adresse électronique
Date de naissance
Projets de recherche
Structures organisationnelles
Fonction
Nom de famille
Simard
Prénom
Manon
Affiliation
Département d'éducation physique, Faculté des sciences de l'éducation, Université Laval
ISNI
ORCID
Identifiant Canadiana
ncf11902478
person.page.name
2 Résultats
Résultats de recherche
Voici les éléments 1 - 2 sur 2
Publication Restreint Comparison of gross visual and microscopic assessment of four anatomic sites to monitor Besnoitia tarandi in barren-ground caribou (Rangifer tarandus groenlandicus)(Wildlife Disease Association, 2012-07-01) Brodeur, Vincent; Beauchamp, Guy; Côté, Steeve D.; Kutz, Susan; Taillon, Joëlle; Simard, Manon; Elkin, Brett; Ducrocq, Julie; Croft, Bruno; Campbell, Mitch; Cooley, Dorothy; Cuyler, Christine; Lair, StéphaneThe objective of this study was to establish a standardized protocol to monitor Besnoitia tarandi prevalence and intensity in barren-ground caribou (Rangifer tarandus) herds by: 1) calculating the relative sensitivity and specificity of the gross visual assessment of four anatomical sites compared with microscopic evaluation, and 2) determining which of four anatomical sampling sites was the most sensitive for detecting B. tarandi cysts by microscopy. Sampled tissues consisted of the conjunctiva of the left eye and skin sections from the rostrum, metatarsus, and thigh from 312 harvested caribou. Diagnosis of infection with B. tarandi was based on observation of at least one cyst by microscopic examination. For each tissue, the maximal density of cysts (number of B. tarandi cysts/mm(2) in the section examined) was calculated for a measured area consisting of the dermis extending from the epidermis of the skin to the base of the hair follicles and adnexal structures. For the conjunctiva, the entire submucosa was evaluated. Gross visual evaluation markedly underestimated B. tarandi prevalence in caribou with a relative sensitivity ranging from 0.29 in the conjunctiva to 0.13 in the skin section from the thigh, whereas relative specificities ranged from 0.98 to 1.00. The metatarsus and rostrum skin sections had the highest probabilities of cyst detection of all four anatomical sampling sites. The metatarsus harbored significantly higher densities of B. tarandi cysts than the rostrum, thigh, or conjunctiva. In conclusion, microscopic evaluation of a skin section from the anterior aspect of the mid-third portion of the metatarsal region could be used as a standardized comparative indicator of density of B. tarandi infection in Rangifer.Publication Restreint Variables associated with Besnoitia tarandi prevalence and cyst density in barren-ground caribou (Rangifer tarandus) populations(Wildlife Disease Association, Inc., 2013-01-01) Côté, Steeve D.; Beauchamp, Guy; Brodeur, Vincent; Kutz, Susan; Taillon, Joëlle; Simard, Manon; Ducrocq, Julie; Lair, StéphaneBesnoitia tarandi has been documented in free-ranging reindeer and caribou (Rangifer tarandus spp.) since 1922 throughout their arctic and subarctic ranges; however, very little is known about its epidemiology. We evaluated variables associated with B. tarandi prevalence and cyst density with the use of barren-ground caribou (Rangifer tarandus) from two migratory herds in northern Quebec: the Rivière-aux-Feuilles and the Rivière-George herds. Diagnosis of infection was made upon the microscopic observation of characteristic cysts in a formalin-fixed section of skin from the anterior aspect of the metatarsus. The density of cysts (number of B. tarandi cysts/mm2) was calculated in a section of the dermis extending from the epidermis of the skin to the base of the hair follicles and adnexal structures. Statistically significant associations between B. tarandi prevalence and cyst density, sex, age, and time of harvest were observed. Male caribou had a slightly higher prevalence compared to females, whereas cyst densities were similar between sexes. We found a nonlinear increase in the odds of infection by B. tarandi by age combined with the opposite trend for intensity of infection. Higher B. tarandi prevalence was observed in caribou sampled in the fall compared to June of the same year, suggesting that transmission is increased during the summer. Higher densities of cysts observed during the fall compared to June of the following year may be the result of the elimination of B. tarandi cysts from the dermis during the winter, or lower winter survival of heavily infected caribou. Comparisons of B. tarandi prevalence and density across herds should take into account these different variables.