We present here a case study that illustrates the potential for the use of logistic regression to facilitate identification of a parasite’s intermediate host. We used a full factorial logistic regression to estimate the probability that adult American alligators (Alligator mississippiensis) were infected with the ascarid nematode Dujardinascaris waltoni given the alligators’ physical characteristics and stomach contents. The strength of association between a fish-based diet and infection predict fish as the intermediate host taxon. Significant but weaker associations with reptile-mammal and reptile-crustacean diets are likely due to the high percentage of alligator remains present in the stomachs examined, with infection likely the result of vertical transmission of the parasites, not the ingestion of these other prey categories. This case study strongly suggests logistic regression has the potential to determine parasite intermediate hosts if definitive host stomach contents can be routinely and adequately sampled and the food items identified to taxa.

Included in

Life Sciences Commons