Geology topics

Ruth M. Duncan

Publications and source records attributed to Ruth M. Duncan.

7 recordsLinked to original sources

USGS1994

Coccidioidomycosis in southern sea otters

Disseminated coccidioidomycosis was diagnosed postmortem in six southern sea otters ( Enhydra lutris nereis ) found dying or dead along the Pacific Coast of California at San Luis Obispo County. These otters were found during winter or summer 1992, 1993, and 1994. Coccidioides immitis was identified by its morphology in tissue impression smears and by histopathology, and was confirmed by culture. Positive serologic results were obtained from four of five sea otters tested. The lungs, pleura, tracheobronchial lymph nodes, liver, and spleen were involved in each case. There was meningeal involvement in half of the affected animals. Coccidioidomycosis has been reported in a wild sea otter only once previously, in 1976, and that otter was also found on the coast of San Luis Obispo County.

Conference Paper↗

USGS1988

An outbreak of type E botulism among common loons ( Gavia immer ) in Michigan's Upper Peninsula

An epizootic of type E botulism (Clostridium botulinum) occurred among common loons (Gavia immer) along the Lake Michigan shore of Michigan's Upper Peninsula (USA) during October and November 1983. An estimated 592 dead loons washed ashore along the Garden Peninsula. Type E botulinal toxin was demonstrated in blood samples and stomach contents of dead loons, and in samples of three species of dead fish found on the Lake Michigan shore. We suspect that loons acquired botulism by ingesting sick or dead fish containing type E toxin.

Michigan↗

USGS1983

Salmonella enteritidis isolated from an eared grebe (Podiceps nigricollis)

The reported prevalence of salmonellosis in wild birds is relatively low, though the number of species of birds reported as having the disease or being carriers of the organism is increasing (Faddoul et al., 1966, Avian Dis. 10: 89- 94). The course of the disease in birds ranges from acute to chronic. Affected birds may recover, become carriers of the organism and periodically shed it into the environment. This paper reports a case of chronic, fatal salmonellosis in an eared grebe.

California↗

USGS1983

Waterbird mortality from botulism type E in Lake Michigan: An update

Three outbreaks of botulism type E occurring in waterbirds on Lake Michigan since autumn 1976 are discussed. Natural ingestion of food containing type E toxin by Ring-billed Gulls ( Larus delawarensis ) and the presence of type E toxin in blood from moribund gulls were demonstrated. Concurrent presence of type C and type E botulinal toxins was found in a die-off of Common Loons ( Gavia immer ). In combination with previous reported outbreaks, these incidents suggest that this disease is geographically widespread in Lake Michigan, and that environmental conditions conducive to type E botulinal toxin production and consumption occur in both summer and autumn.

Lake Michigan↗

USGS1980

Bordetella bronchiseptica associated with pulmonary disease in mountain voles (Microtus montanus)

Bordetella bronchiseptica was isolated from the lungs of all of six mountain voles ( Microtus montanus ) found dead or dying of pulmonary infection near the Bear River Research Station in northern Utah in January, 1973. The possibility of concomitant viral or mycoplasmal infection was not ruled out.

Utah↗

USGS1980

The susceptibility of the mallard duck (Anas platyrhynchos) to Clostridium botulinum C2 toxin

Most strains of Clostridium botulinum type C, after having lost their capacity to produce their dominant toxin (C 1 ) as a result of being“cured”of their prophages, continue to produce C 2 , a trypsin-activable toxin reported by other investigators. While of relatively low toxicity when administered perorally to the adult mallard duck ( Anas platyrhynchos ), it was highly toxic when given parenterally. By the intravenous route, for example, it was more than 1, 000 times as toxic as C 1 toxin by the same route, when compared on the basis of mouse intraperitoneal toxicity. The cause of death in every instance was massive pulmonary edema and hemorrhage rather than the respiratory paralysis that occurs in C 1 intoxication. 抄録

Japanese Journal of Medical Science and Biology↗

USGS1976

A relationship between avian carcasses and living invertebrates in the epizootiology of avian botulism

A survey of the sources of Clostridium botulinum type C toxin possibly utilized as food by aquatic birds in an epizootic area of avian botulism in northern Utah showed that living aquatic and terrestrial invertebrates normally found in close association with dead, decomposing birds commonly carried the toxin. Of 461 samples associated with 21 species of avian carcasses, 198 were toxin-positive. Invertebrate species not normally scavengers of vertebrate tissues were less commonly and less highly toxic, particularly when captured 30 cm or more from a carcass; six of 237 samples of such aquatic invertebrates contained low-level toxin. Of the species tested, blow fly larvae (Calliphoridae) were the most consistently and highly toxic, although others, particularly adult and larval stages of several species of beetles (Coleoptera), contained toxin at levels probably significant in the epizootiology of the disease. An estimated 0.05 to 0.25 g of the most toxic fly larvae or 15 g of the most toxic beetles tested carried a mediam lethal dose for an adult mallard duck. Examination of stomach contents of aquatic birds dead of botulism showed that some had consumed invertebrates.

Utah↗