In vitro effect of herbal products against Histomonas meleagridis

The ban on chemotherapeutics against Histomonas meleagridis in the European Union has left turkey producers without an effective treatment against histomonosis. It has encouraged the development of alternative control methods amongst which are a number of herbal products. In the present study the in vitro effect of four herbal products against H. meleagridis was examined. After suspension of the herbal products in Dwyer's culture medium used for subculturing of a viable culture, parasite growth was monitored by frequently counting the histomonads until 72 h of incubation. The solid products Aromabiotic™, Enteroguard™, and Protophyt SP™ as well as the positive control products dimetridazole and Histostat-50™, were tested in twofold serial dilutions ranging in concentration from 400 to 12.5 μg/mL, while the liquid product Protophyt B™ was tested in concentrations ranging from 0.24% to 0.008% (v/v). The herbal products Enteroguard™ and Protophyt B™ as well as dimetridazole and Histostat-50™, two chemotherapeutics with known antihistomonal activity, inhibited the growth of H. meleagridis, while no antihistomonal effect was found for Aromabiotic™ and Protophyt SP™.