Research about Illinois, Ontario, Wisconsin

USGS1984

Renal coccidiosis in interior Canada geese, Branta canadensis interior Todd, of the Mississippi Valley population

Kidneys from 309 Interior Canada geese from three locations in the Mississippi Flyway were examined for renal coccidia. Oocysts and/or young zygotes of Eimeria sp. were found in 6.8% of goose kidneys sampled. Only one type of renal coccidian oocyst was observed. Significantly more immature geese were infected than adults; however, there was no significant difference observed between the prevalences of infection in male and female birds. A host cellular response to zygotes and oocysts was noted in the majority of infected adult geese. Heavily infected kidneys were hypertrophic with minute foci on the surface of the organ. Histological examinations showed large numbers of unsporulated oocysts accumulated in distended collecting tubules, resulting in pressure necrosis to adjacent tissue and urate retention. Zygotes were observed in the cytoplasm of tubule cells and extracellularly in interstitial tissue. Infected tubule cells were characterized by the peripheral location of the nuclei, cytoplasmic basophilia, and cellular hypertrophy. This is the first report of an Eimeria sp. in the kidneys of Canada geese of the Mississippi Valley population.

Illinois, Ontario, Wisconsin↗

USGS1982

A study of gizzard nematodes and renal coccidiosis in Canada geese (Branta canadensis interior) of the Mississippi Valley population

A total of 309 Mississippi Valley Population Canada geese, Branta canadensis interior , of different sex and age groups was collected from three locations in the Mississippi Flyway from 1979-1981 and examined for gizzard nematodes and renal coccidia. Three species of nematodes were removed from the gizzards, Amidostomum anseris, A. spatulatum, and Epomidiostomum crami. The latter two species are reported from this population of geese for the first time. Gizzard nematodes were found in 95.2% of all Canada geese examined, with A. anseris being the most abundant of the three species. There was no statistically significant difference between immatures and adults in the abundance of total nematodes species however, immature geese carried significantly more A. anseris and adult geese harbored significantly more A. spatulatum and E. crami infections. No significant difference in gizzard worm infections between male and female birds was observed. The abundance of overall gizzard nematodes was greatest in Canada geese from Winisk, Ontario (11.9), but the abundance of worms in southern Illinois geese (10.0) was similar. Geese from Horicon National Wildlife Refuge had the lowest abundance of infection, 7.5. The overall abundance of nematodes showed a general increase the second year of the study in each sex and age group and at each collection area. Each of three species of nematodes was responsible for some degree of damage to the gizzard lining and koilin, but E. crami was the most pathogenic of the species recovered. The occurrence of renal coccidiosis in Canada geese of this flyway is reported for the first time; the etiologic agent is Eimeria clarkei. The oocysts and/or endogenous stages of E. clarkei were present in 6.8% of the Canada geese sampled and this was the only species found. Male and female geese showed no significant differences in E. clarkei infections, however, significantly more immature geese than adult geese were infected with this species. A cell mediated response to the presence of E. clarkei oocysts and endogenous stages was seen in 83.3% of infected adult geese, but only 20% of immature geese showed a macrophage response to the infective stages of this parasite. A massive E. clarkei infection caused the death of one goose collected at Horicon National Wildlife Refuge. Amidostomiasis, epomidiostomiasis, and renal coccidiosis were important pathogenic diseases in the Mississippi Valley Population Canada geese but did not directly cause significant mortality in the population.

Illinois, Ontario, Wisconsin↗