Evaluation of the in vivo anthelmintic properties of Mitragyna inermis (Willd.) as a livestock dewormer against parasitic hematophagous worm Haemonchus contortus infections in different breeds of lambs.

Gastrointestinal (GI) nematodes remain a major constraint on livestock production throughout the world. This study assessed the in vivo efficacy of the powder of Mitragyna inermis leaves in three breeds of lambs, namely, West African dwarf lambs (WAD), West African long-legged lambs (WALL), and F1 lambs (cross of a WALL ram with a WAD ewe), artificially infected with 3000 L3s of Haemonchus contortus in a controlled experiment. Fecal sample examination, serological analysis, and necropsy were carried out to determine the egg count, worm burden, and worm fecundity reduction. A dose of 3.2 g/kg body weight (BW) M. inermis was administered per the oral route for three consecutive days and repeated 2 weeks later. Compared with the control, the powder of M. inermis leaves (> 60%) and albendazole (100%) significantly reduced (p < 0.01) fecal egg counts (FECs) in the three breeds of lambs. The posttreatment reduction in FECs fluctuated from 56.99 to 78.75% for WAD lambs, 38.39 to 66.39% for WALL lambs, and 35.55 to 63.11% for F1 lambs (WALL × WAD). Significant differences (p < 0.05) were observed in packed cell volume values before and after infection. M. inermis reduced the egg-laying capacity of female adult worms by up to 60% and eliminated more than 80% of the adult worms of H. contortus in lambs. Furthermore, albendazole reduced the worm count and fecundity of female worms by greater amounts than M. inermis (100%). The findings of this study showed that M. inermis is a good source of bioactive compounds for drug development. According to this result, a 3.2 g/kg BW dose of the plant could be applied for the control of GI nematodes in small ruminants.