Comparison of Organ Weights of Wild and Laboratory Microtus montanus infected with Trypanosoma brucei gambiense
Seed JR, Pinter AJ, Ashman PU, Ackerman S, King L. 1978. Comparison of Organ Weights of Wild and Laboratory Microtus montanus infected with Trypanosoma brucei gambiense. The American Midland Naturalist. 100(1):126-134
A preliminary survey of male Microtus montanus trapped at Jackson Hole, Wyoming, indicated that 100% of these animals harbored one or more endo-and/or ectoparasites. Spleen histology and differential white blood cell counts were both consistent with the suggestion that these animals have persistent parasitic infections, which serve as a stimulus to the immune response. It has also been demonstrated that there is a high percentage of splenomegaly in these animals. These results support the hypothesis that splenomegaly in Microtus montanus is caused by a parasitic infection, and therefore, that splenomegaly can be used as a survey marker to determine the extent of parasitism in field populations. It has also been shown in adult males captured during a 3-year period that there was a significant inverse relationship between spleen size and gonadal weights. It is assumed that smaller gonads denote reduced reproductive potential. Therefore, parasitic infections, by reducing this potential, may have a greater effect on the control of population density than previously suggested. Other hypotheses on the mechanisms of population density control are discussed.
- Type
- Journal Article
- Authors
- Seed, John; Pinter, Aelita; Ashman, Portia; Ackerman, Steven; King, Lucy
- Units
- GRTE
- Keywords
- Animal Studies, Caldera, Detachment faulting, Eruption, Heise, IAR, Idaho, ignimbrite, Seismology, Volcanic field