Successful treatment of Trypanoxyuris sp. infection in naturally infected southern brown-howlers ( Alouatta guariba clamitans ).

Southern brown-howler monkeys ( Alouatta guariba clamitans ) may harbor Trypanoxyuris sp., a pinworm parasite with documented fatal consequences in this species. Despite this risk, effective treatment protocols remain unclear. Therefore, the present study aimed to evaluate the efficacy of two anthelmintic protocols against natural infections in two brown-howler monkeys received at the Wild Animal Care and Rehabilitation Sector (SARAS-CAV-UDESC). The protocols utilized pyrantel pamoate & praziquantel (600.0 mg, PO, single dose) and albendazole (20.0 mg, PO, daily for 5 days). Fecal egg counts were carried out daily at the Laboratory of Parasitology and Parasitic Diseases (LAPAR-CAV-UDESC) before and after drug administration. Both treatments successfully eliminated Trypanoxyuris sp. infections. The animal treated with pyrantel pamoate & praziquantel achieved egg clearance by day 6 (144 h), demonstrating effectiveness with a single administration. Albendazole cleared the infection within 2 days of treatment, indicating its potential as a fast-acting treatment. No adverse effect were observed in the treated monkeys. These findings contribute to the development of evidence-based treatment protocols for Trypanoxyuris sp. in primates, enhancing animal health and welfare of captive and wild populations.