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Since 1991, blood-covered eggs have been noted in nests of Ross’s (Chen rossii (Cassin, 1861)) and lesser snow (Chen caerulescens caerulescens (L., 1758)) geese at the Karrak Lake colony, Nunavut, Canada. Fleas (Ceratophyllus vagabundus vagabundus (Boheman, 1866)) were subsequently observed to be associated with goose nests containing eggs covered with dried blood. We examined prevalence of blood presence on goose eggs and extent of egg coverage with blood in goose nests from 2001 to 2004. Flea abundance in nests was estimated in 2003 and 2004, and was strongly correlated with the proportion of goose egg surface covered by blood, suggesting that degree of blood coverage was a suitable index of flea abundance. Extent of blood fluctuated annually and was correlated with both host characteristics and host habitat factors. Nest bowls used by geese in previous years contained more fleas than did new nest bowls, and fleas were more abundant in older areas of the colony. Flea abundance increased with goose clutch size and was highest in rock and birch habitats. Ceratophyllus vagabundus vagabundus appears to be a new parasite of geese at Karrak Lake; flea abundance may change in response to increased availability of favorable habitat, which is expected if local climate warms. Depuis 1991, on observe des oeufs recouverts de sang dans les nids des oies de Ross (Chen rossii (Cassin, 1861)) et des petites oies des neiges (Chen caerulescens caerulescens (L., 1758)) dans la colonie du lac Karrak, Nunavut, Canada. On a ensuite associé la présence de puces (Ceratophyllus vagabundus vagabundus (Boheman, 1866)) aux nids d’oies contenant des oeufs recouverts de sang séché. Nous avons examiné la prévalence de la présence de sang sur les oeufs d’oies et l’étendue de la couverture de sang dans les nids d’oies de 2001 à 2004. Nous avons estimé l’abondance des puces dans les nids en 2003 et 2004; celle-ci est en forte corrélation avec la proportion de la surface des oeufs d’oies recouverte de sang, ce qui laisse penser que l’importance de la couverture de sang est un bon indice de l’abondance des puces. L’importance du sang varie d’une année à l’autre et est en corrélation avec tant les caractéristiques de l’hôte que les facteurs de l’habitat de l’hôte. Les cuvettes de nidification utilisées les années antérieures contiennent plus de puces que les nouvelles cuvettes de nidification et les puces sont plus abondantes dans les zones plus anciennes de la colonie. L’abondance des puces augmente en fonction de la taille de la couvée des oies et elle est maximale dans les habitats de pierres et de bouleaux. Ceratophyllus vagabundus vagabundus semble être un nouveau parasite des oies au lac Karrak; on s’attend à ce que l’abondance des puces change en réaction à la disponibilité accrue d’habitats favorables prévue dans le cas d’un réchauffement du climat local. [ABSTRACT FROM AUTHOR]

Presents the study redescribing the sarcocysts of Sarcocystis rileyi (Apicomplexa: Sarcocystidae). Identification of the intermediate hosts for Sarcocystis rileyi; Assessment of the types of specimens for the study; Investigation of the sections of pectoral muscles.

ABSTRACT We describe 4 years of an experimental rotation in ecosystem health offered to senior veterinary students in Canada. Faculty from the four Canadian veterinary colleges collaborated in offering the rotation once annually at one of the colleges. The first rotation was held in Guelph, Ontario, in 1993, followed in successive years by rotations at Saskatoon, Saskatchewan, Saint-Hyacinthe, Québec, and Charlottetown, Prince Edward Island. The rotation is a predominantly field-based experience that allows students to work with veterinary and other role models who are actively engaged in clinical research related to ecosystem health. Five specific field studies that worked particularly well during the rotations are presented. These studies involved investigating mortality in wildlife due to botulism, designing an environmental surveillance system around herds of beef cattle, using belugas to evaluate the health of the St. Lawrence River, dealing with competition for water use by aquaculture and agriculture, and exploring the role of veterinarians during major coastal oil spills. The experience has resulted in our developing the subject matter, field examples, teaching approach, and confidence necessary to make ecosystem health the focus of a productive clinical rotation for senior year veterinary students. [ABSTRACT FROM AUTHOR]