evaluation of anthelmintic activity of different fractions of azadirachta indica a. juss seed extract

This investigation was aimed at determination of anthelmintic activity of different fractions of Azadirachta indica seed prepared from the crude aqueous methanol extract (CAME). For this purpose, eggs and adult Haemonchus contortus were exposed to aqueous, ethyl acetate, chloroform and petroleum spirit fractions of A. indica seeds employing standard bioassays. All the fractions of A. indica seeds exhibited dose and/or time dependent ovicidal and wormicidal effects against H. contortus. The best ovicidal activity was demonstrated by the ethyl acetate fraction with LC50=21.32 µg/ml; whereas, it was 6-14 times lower for the other fractions. Likewise, ethyl acetate fraction @ 50 mg ml-1 exhibited the best wormicidal effects by killing 83% adult H. contortus one hour post-exposure. For in vivo anthelmintic activity faecal egg count reduction test was perform on sheep naturally infected with helminthes. Maximum reduction (98.9%) was observed with CAME. Therefore, it is concluded that future studies aimed at identification of active anthelmintic principles of A. indica may be focused on ethyl acetate fraction of the plant.