First record of gastrointestinal parasites in the Indian Little Swift (𝘈𝘱𝘶𝘴 𝘢𝘧𝘧𝘪𝘯𝘪𝘴 𝘴𝘪𝘯𝘨𝘢𝘭𝘦𝘯𝘴𝘪𝘴) in Sri Lanka

Abstract

The Indian Little Swift, belonging to family Apodidae, are resident breeding birds in Sri Lanka and can act as vectors capable of transmitting zoonotic pathogens. Bird droppings are a significant pathway for disease transmission, as pathogens can spread efficiently through the consumption of tainted water and the inhalation of contaminated airborne particles. This study records the first microscopic identification of gastrointestinal (GI) parasites in the droppings of the Indian Little Swift in the University of Peradeniya, Sri Lanka. Fresh faecal samples were collected from May to July 2025, directly from their droppings beneath nesting colonies located in 8 different areas of the University of Peradeniya. Samples were microscopically analysed using iodine wet method and fecal flotation technique to detect nematode eggs, trematode eggs, protozoan cysts, and oocysts. Out of eight nesting sites (representing ~18 – 60 individuals), droppings were detected only from six sites while no droppings were found beneath two nesting sites. Fecal flotation analysis revealed that the swifts were positive for both protozoans and helminths, including 𝘌𝘪𝘮𝘦𝘳𝘪𝘢 spp., 𝘈𝘴𝘤𝘢𝘳𝘪𝘥𝘪𝘢 spp., 𝘚𝘵𝘳𝘰𝘯𝘨𝘺𝘭𝘰𝘪𝘥𝘦𝘴 spp., 𝘏𝘦𝘵𝘦𝘳𝘢𝘬𝘪𝘴 spp., 𝘊𝘢𝘱𝘪𝘭𝘭𝘢𝘳𝘪𝘢 spp., trematode-type eggs, and hookworm eggs. A type of sporulated coccidian oocyst, suggestive of the family Adeleidae and typically containing about ten sporocysts per oocyst was also detected, reflecting the insectivorous diet of the little swift. No parasitic stages could be observed by using iodine wet mounts/direct smears. Hookworms were detected in five out of the six nesting sites showing high infection intensities. In contrast, 𝘈𝘴𝘤𝘢𝘳𝘪𝘥𝘪𝘢 and 𝘏𝘦𝘵𝘢𝘳𝘢𝘬𝘪𝘴 were confined only in one nesting site exhibiting lower parasite burden. These findings provide important insights into the diversity of parasitic infections in the Indian Little Swift in Sri Lanka, enhancing the understanding of their zoonotic potential and their role as reservoir hosts for poultry.