This study was carried out to assess the anthelmintic activity of Acacia nilotica bark and leave extracts in different solvents. Adult motility assay, egg hatch test and fecal egg count reduction test were carried out to evaluate the anthelmintic activity. Effect of plant extracts both of leaves and bark of A. nilotica was dose-dependent. Highest mortality of worms was observed 12 hours post-exposure @ 25 mg/ml. Extracts of leaves were more potent than the bark extracts. Ethyle acetate fractions both of bark and leaves exhibited higher anthelmintic effects compared with chloroform, petroleum spirit and aqueous fractions. Crude aqueous methanol extract (CAME) of bark (LC₅₀= 201.0032 µg/ml) had higher inhibitory effects compared with that of leaves (LC₅₀= 769.2485 µg/ml) on egg hatching. Likewise, chloroform and ethyle acetate fractions of A. nilotica bark exhibited higher ovicidal activity. In vivo, maximum reduction (72.01%) in fecal egg counts was recorded for CAME of bark followed by CAME of leaves (63.44%) @ 8 g/kg at day 12 post-treatment. Results suggest lipophilic nature of the active principles having anthelmintic efficacy in A. nilotica bark and leaves.

Key words: Acacia nilotica; Anthelmintic; Pakistan; Sheep