Prevalence of Helminthiasis Among African Elephants in Tsavo and Laikipia-Samburu Ecosystems, Kenya

African elephants maintain a delicate balance between high intestinal helminth numbers and symptoms of poor health. However, calves and weaners face survival threats from damage caused by helminth infections and infestations during periods of starvation. Using coprological evaluations, we compared helminth infection patterns and selected risk factors in elephants from Tsavo and the Laikipia-Samburu ecosystem (LSE). Eggs and adult worms were identified and classified into genera using morphological and morphometric characteristics. Overall prevalence rates were high at 95.6% and 98.5% for Tsavo and Laikipia-Samburu, respectively, and 97.1% in total. Using the chi-squared test of independence, nematode prevalence rates (97.1%) were significantly different from trematodes (32.6%) (χ2(1) = 248.84, p < 0.001). Prevalence rates did not differ across age classes in the two populations. Using the Generalized Linear Model, sex had an independent significant effect on the observed mean worm burdens (F(1) = 5.842, p = 0.016, CI 95%), but neither age nor location did. However, the interaction had a significant effect on mean eggs per gram (EPGs) observed between age and location (F(1) = 14.043, p < 0.0005, CI 95%) and between age and sex (F(1) = 4.858, p = 0.028, CI 95%). Some of the identified helminth species may potentially lead to life-threatening gut mucosa hemorrhaging and ulcerations, particularly during stressful conditions, although the animals were not clinically evaluated.