In vitro susceptibility testing of Trichomonas gallinae strains to proton pump inhibitors and nitroimidazoles.

Trichomonas gallinae is a unicellular obligate parasite predominantly spread among Columbiformes through the sharing of feeding and drinking stations, as well as during the feeding of squabs with crop milk. It primarily causes lesions in the pharynx and esophagus, impairing the birds' ability to eat, drink, and even breathe, thus it is potentially fatal for infected birds. Currently, five nitroimidazole derivatives are available for treatment, which, however, are prohibited for use in food-producing livestock. The aim of this study is to explore alternative treatment options against Trichomonas gallinae. Parasites were collected from urban pigeons using a sterile swab from the trachea. The number of live trophozoites (per mL) was determined using a Burker chamber. Subsequently, they were treated with solutions of pantoprazole, rabeprazole dissolved in distilled water, and omeprazole, esomeprazole, and lansoprazole dissolved in ethanol. Omeprazole was found to be the most effective, achieving complete eradication at a concentration of 250 µg/mL, whereas pantoprazole and esomeprazole required a concentration of 1000 µg/mL to achieve the same result. Rabeprazole and lansoprazole were significantly less effective, requiring a concentrations of 2000 µg/mL and 4000 µg/mL for complete eradication, respectively. Overall, our findings suggest that proton pump inhibitors may serve as viable alternative treatment options for Trichomonas gallinae infection. The development of benzimidazole-structured compounds appears promising for the future creation and testing of new, alternative, and safer agents.