In vitro anthelmintic activity of Vachellia aroma and Libidibia paraguariensis fruit extracts against Haemonchus contortus

Abstract

Haemonchus contortus is a major parasite affecting sheep production, causing significant economic losses in animal health and production. Due to increasing resistance levels developed by the indiscriminate use of synthetic antiparasitic drugs, there is growing interest in exploring non-chemical control strategies. Thus, the aim of this work was to evaluate the in vitro anthelmintic activity of aqueous and methanolic extracts of Vachellia aroma and Libidibia paraguariensis fruits and detect the secondary metabolites present in the extracts. The anthelmintic activity of the extracts was evaluated by egg hatching and larval migration inhibition assays, and phytochemical screening was performed by thin-layer chromatography. In the egg hatching inhibition assay, both plant extracts demonstrated 100% efficacy at the highest concentration evaluated (50 mg/ml). In the larval migration inhibition assay, the highest activity of the aqueous and methanolic extracts of L. paraguariensis was 26.09% at 50 mg/ml and 56.57% at 12.5 mg/ml respectively, in contrast that of the aqueous and methanolic extracts of V. aroma was 14.51% and 27.73% at 50 mg/ml. The secondary metabolites detected in the methanolic extract of V. aroma were coumarins, flavonoids, saponins and tannins, whereas those detected in the aqueous extract were only coumarins and flavonoids. In both L. paraguariensis extracts, the secondary metabolites detected were flavonoids, saponins and tannins, whereas coumarins were detected only in the methanolic extract. Given the anthelmintic activity exhibited by these plant species against egg hatching and larval migration, these fruits can be considered a valuable tool for the control of H. contortus.