Anti-coccidial properties and mechanisms of an edible herb, Bidens pilosa , and its active compounds for coccidiosis

Avian coccidiosis is an economically important disease in the poultry industry. In view of the disadvantages of anti-coccidial drugs in chickens, edible plants and their compounds are re-emerging as an alternative strategy to combat this disease. A previous publication reported that the edible plant B . pilosa showed promise for use against coccidiosis. Here, we first investigated into the anti-coccidial effects of B . pilosa . We found that B . pilosa at 100 ppm or more significantly suppressed E . tenella as evidenced by reduction in mortality rate, oocyst excretion and gut pathological severity in chickens and its minimum prophylactic duration was 3 days. Next, we explored the mode of action of anti-coccidial mechanism of B . pilosa . The E . tenella oocysts were not directly killed by B . pilosa ; however, administration of the plant suppressed oocyst sporulation, sporozoite invasion, and schizonts in the life cycle of E . tenella . Besides, B . pilosa boosted T cell-mediated immunity. Finally, we characterized the related anti-coccidial phytochemicals and their mode of action. One of three potent polyynes present in B . pilsoa , Compound 1 (cytopiloyne), acted against coccidiosis in chickens in a similar manner to B . pilosa . These data illustrate the anti-coccidial potency and mechanism of B . pilosa and one of its active compounds, and provide a cornerstone for development of novel herbal remedies for avian coccidiosis.