In vitro evaluation of anthelmintic efficacy of bromelain against goat gastrointestinal nematodes

Widespread occurrence of resistance to commonly used chemotherapeutic anthelmintics in gastrointestinal nematodes (GIN) of sheep and goats has necessitated the need for other alternative control methods, including the use of natural products with anthelmintic properties. In this study we evaluated the in vitro action of stem bromelain, a plant-derived cysteine proteinase, on the development of goat GIN. Anthelmintic activity of bromelain was evaluated at various concentrations using egg hatch assay (EHA) and larval development assay (LDA). The EC₅₀ in the EHA was 2.559 mg/mL and in the LDA was 0.013, showing a dose-dependent relationship. Bromelain at 150 μM concentration demonstrated significant adulticidal action on Haemonchus contortus, killing all the worms after 8 hrs of incubation by damaging their cuticle and ultimately causing disintegration of the worms. These results suggest that bromelain may be useful in the control of GIN of small ruminants. However, suitable in vivo studies in the natural hosts are still necessary to confirm the efficacy.