Comparative Helminthology of Wild and Captive African Pangolins (Manis tricuspis) in South South Nigeria: Filling a Parasitological Gap

This study conducts a comparative analysis of helminth parasite assemblages in wild-caught and rehabilitation-captive African white-bellied pangolins Manis tricuspis in Delta and Edo States, South South Nigeria, addressing a critical gap in pangolin parasitology in West Africa. Pangolins submitted for wildlife rehabilitation programmes carry parasitic loads whose composition, intensity, and potential zoonotic significance are poorly known, creating challenges for captive management and rewilding decisions. Using a cross-sectional design, gastrointestinal and respiratory parasite burdens were characterised in 42 wild-caught individuals and 28 captive rehabilitation animals. Standard parasitological dissection, morphological identification, and molecular barcoding (COI and 18S rDNA) were used. Haematological parameters and condition indices were compared between parasitised and non-parasitised individuals. A total of nine helminth species were identified, comprising four nematode, three trematode, and two cestode species. Wild individuals showed significantly higher helminth species richness and infection intensity. A previously undescribed oxyurid nematode was recovered from three wild individuals and is proposed as a new species based on morphological and molecular evidence. Captive animals showed parasite simplification consistent with acquired immunity reduction under captivity. Condition factor was significantly lower in animals with high nematode intensity. The study provides the first comprehensive helminth inventory for West African pangolins and delivers treatment protocol recommendations for rehabilitation centres managing Manis tricuspis in Nigeria. Keywords: helminths, Manis tricuspis, pangolin parasitology, South South Nigeria, wildlife rehabilitation.