Whipworm ( Trichuris dipodomys ) infection in kangaroo rats ( Dipodomys spp.): effects on digestive efficiency

To determine whether infections by whipworms (Trichuris dipodomys (Nematoda: Trichurata: Trichuridae)) might affect digestive efficiency and therefore energy budgets of two species of kangaroo rats (Dipodomys microps and Dipodomys ordii (Rodentia: Heteromyidae)), we compared the apparent dry matter digestibility of three groups of hosts: those naturally infected with whipworms, those naturally uninfected with whipworms, and those origi- nally naturally infected but later deinfected by treatment with the anthelminthic Ivermectin. Prevalence of T. dipodomys was higher in D. microps (53%) than in D. ordii (14%). Apparent dry matter digestibility was reduced by whipworm infection in D. microps but not in D. ordii. Although a statistically significant effect was shown, its small mag- nitude indicates that whipworm infection is unlikely to have a biologically significant impact on the energy budgets of host kangaroo rats.