Murray State University
Blood and Fecal Parasites of the Tiger Salamander (Ambystoma tigrinum nebulosum) According to Life Stage
Institution
Murray State University
Faculty Advisor/ Mentor
Howard Whiteman; Leon Duobinis-Gray
Abstract
This study provides a unique look at differences in parasite prevalence within two life stages of tiger salamanders, Ambystoma tigrinum nebulosum. Individuals in the paedomorphic life stage reach maturity while retaining larval characteristics such as gills and a membranous tail. It is also these characteristics that bind them to an aquatic lifestyle. Metamorphic individuals commonly transform before becoming adults and lose their larval characteristics, allowing them to enter the terrestrial environment. These life stages separate the individuals into two ecosystems (aquatic and terrestrial) that suggest that differences between parasites in the same host species might occur according to life phase. Juveniles were also sampled for parasites, providing a third life stage for comparison. Within juvenile stages a cannibalistic morph, characterized by a wider mouth and enlarged "teeth", also occurs. We hypothesized that metamorphic adults should have higher prevalence of blood parasites (e.g., trypanosomes) due to increased exposure to vectors and that cannibals should have a higher prevalence of intestinal parasites because of increased exposure after eating infected larvae. Blood and fecal samples of tiger salamanders were collected from ponds in south-central Colorado in 2004-05. Blood smears (N =128) were prepared in the field while parasite eggs (N > 100) were separated from fecal samples with a sucrose gradient floatation and prepared for observation under a microscope. Results of both analysis will be presented.
Blood and Fecal Parasites of the Tiger Salamander (Ambystoma tigrinum nebulosum) According to Life Stage
This study provides a unique look at differences in parasite prevalence within two life stages of tiger salamanders, Ambystoma tigrinum nebulosum. Individuals in the paedomorphic life stage reach maturity while retaining larval characteristics such as gills and a membranous tail. It is also these characteristics that bind them to an aquatic lifestyle. Metamorphic individuals commonly transform before becoming adults and lose their larval characteristics, allowing them to enter the terrestrial environment. These life stages separate the individuals into two ecosystems (aquatic and terrestrial) that suggest that differences between parasites in the same host species might occur according to life phase. Juveniles were also sampled for parasites, providing a third life stage for comparison. Within juvenile stages a cannibalistic morph, characterized by a wider mouth and enlarged "teeth", also occurs. We hypothesized that metamorphic adults should have higher prevalence of blood parasites (e.g., trypanosomes) due to increased exposure to vectors and that cannibals should have a higher prevalence of intestinal parasites because of increased exposure after eating infected larvae. Blood and fecal samples of tiger salamanders were collected from ponds in south-central Colorado in 2004-05. Blood smears (N =128) were prepared in the field while parasite eggs (N > 100) were separated from fecal samples with a sucrose gradient floatation and prepared for observation under a microscope. Results of both analysis will be presented.