Salmonella infections in a marsupial, the quokka (Setonix brachyurus), in relation to seasonal changes in condition and environmental stress

An unusual abundance of Salmonella infections was studied in an island population of a wild marsupial, the quokka (Setonix brachyurus), which experiences starvation in summer associated with significant mortality. The frequency of infections was found to vary seasonally over most parts of the island, with high infection rates (70 to 100%) in summer and low infection rates (0 to 30%) in winter. In some samples, there was an average of as many as two isolations per animal, and up to five isolations were made from a single animal. By the end of summer, virtually all animals excreted Salmonella spp., with a median rate of excretion of approximately 3,000 Salmonella organisms per g of feces. The seasonal changes occurred over intervals of only weeks. The infections are believed to be associated with disruption of the digestive physiology of the animals caused by the poor quality of feed available in summer. This conclusion was supported by a quantitative study of the infections and by a field manipulation experiment which delayed the initiation of the infections as long as a food supplement was available. The proliferation of Salmonella spp. is discussed in terms of the ecology of the quokka and of the use of Salmonella spp. as indicators of environmental stress acting on the animals.

[1]  T. Speed,et al.  A study of isolation procedures for multiple infections of Salmonella and Arizona in a wild marsupial, the quokka (Setonix brachyurus). , 1982, The Journal of applied bacteriology.

[2]  A. Main,et al.  Condition, body composition and total body water estimation in the quokka, Setonix brachyurus (Macropodidae). , 1980 .

[3]  S. Bradshaw,et al.  Adrenocortical function and a field population of a macropodid marsupial (Setonix brachyurus, Quoy and Gaimard). , 1979, The Journal of endocrinology.

[4]  R. J. Lysons,et al.  The inhibitory effect of bovine rumen fluid on Salmonella typhimurium. , 1979, Research in veterinary science.

[5]  R. Rubin,et al.  Salmonellosis: Microbiologic, pathologic, and clinical features , 1977 .

[6]  A. Herrer,et al.  Panamanian forest mammals as carriers of Salmonella. , 1976, The American journal of tropical medicine and hygiene.

[7]  M. Kourany,et al.  A survey to assess potential disease hazards along proposed sea level canal routes in Panamá and Colombia. VIII. Survey of enterobacterial pathogens in wild-caught vertebrates. , 1975, Military medicine.

[8]  S. Bradshaw,et al.  Salmonella javiana infection in an infant associated with a marsupial, the quokka, Setonix brachyurus, in Western Australia , 1973, Journal of Hygiene.

[9]  J. Iveson Enrichment procedures for the isolation of Salmonella, Arizona, Edwardsiella and Shigella from faeces , 1973, Journal of Hygiene.

[10]  G. Tannock,et al.  The effect of food and water deprivation (stress) on Salmonella-carrier mice. , 1972, Journal of medical microbiology.

[11]  D. Kitchener The importance of shelter to the Quokka, Setonix brachyurus (Marsupialia), on Rottnest Island , 1972 .

[12]  J. Iveson Strontium chloride B and E.E. enrichment broth media for the isolation of Edwardsiella, Salmonella and Arizona species from tiger snakes , 1971, Journal of Hygiene.

[13]  C. R. Schneider,et al.  Panamanian amphibians and reptiles as carriers of Salmonella. , 1970, The American journal of tropical medicine and hygiene.

[14]  M. Kourany,et al.  A survey for enteropathogenic bacteria in Panamanian primates. , 1969, Laboratory animal care.

[15]  M. G. Smith,et al.  Effects of food intake on numbers of salmonellae and Escherichia coli in rumen and faeces of sheep. , 1969, The Journal of applied bacteriology.

[16]  F. Grau,et al.  Effect of some preslaughter treatments on the Salmonella population in the bovine rumen and faeces. , 1968, The Journal of applied bacteriology.

[17]  L. Williams,et al.  Patterns of Salmonella excretion in market swine. , 1967, American journal of public health and the nation's health.

[18]  G. Storr Studies on Marsupial Nutrition IV. Diet of the Quokka, Setonix Brachyurus (Quoy & Gaimard), on Rottnest Island, Western Australia , 1964 .

[19]  B. Kakulas Myopathy affecting the Rottnest Quokka (Setonix brachyurus) reversed by α-Tocopherol , 1961, Nature.

[20]  S. Barker Studies on Marsupial Nutrition III. The Copper-Molybdenum-Inorganic Sulphate Interaction in the Rottnest Quokka, Setonix Brachyurus (Quoy & Gaimard) , 1961 .

[21]  P. Bentley Some aspects of the water metabolism of an Australian marsupial Setonyx brachyurus , 1955, The Journal of physiology.