Status of parasitic infections in migratory birds in selected areas of Bangladesh.

Migratory birds are a source of natural beauty and help in maintaining ecosystems, pest control and pollination. However, as with other pathogens, gastrointestinal (GI) parasites residing within migratory birds consequently contaminate the environment through their droppings. The study was aimed at identifying and estimating the prevalence and spatial distribution of GI parasites in migratory birds. To do this, 265 fecal samples were collected, (Bangladesh Livestock Research Institute (BLRI) Lake, Dhaka: 203), (Tanguar Haor, Sunamganj: 62), from October 2022 to March 2023. Samples were processed and examined using flotation and sedimentation techniques. Overall prevalence of parasites was 19.2% (51 out of 265). Parasites belonging to ten genera were identified, including Ascarid (2.3%), Capillaria (2.3%), Echinuria (0.8%), Heterakis (0.8%), nematode larva (3.4%), Strongyloides (1.9%), Tetrameres (0.8%), Echinostome (4.5%), Raillietina (1.1%), Eimeria (2.6%) and Isospora (2.3%). We detected the highest infections caused by nematodes (10.9%), followed by protozoa (4.9%), trematodes (4.5%), and cestodes (1.1%). Infections were almost equal in Tanguar Haor (19.4%) and the BLRI lake (19.2%). Statistically significant variation among nematode, trematode, cestode and protozoan infections were detected at the BLRI lake (p<0.001) but were insignificant (p>0.05) at Tanguar Haor. Most importantly, we also detected zoonotic parasites (4.5%), suggesting potential zoonotic relevance. This indicates that strict guidelines regarding hygienic measures while visiting areas densely populated with migratory birds should be circulated.