Abstract

IN VITRO ANTHELMINTIC EFFICACY OF AQUEOUS EXTRACTS DERIVED FROM CHAMAECRISTA NIGRICANS AND TEPHROSIA PEDICELLATA AGAINST THE PARASITE HAEMONCHUS CONTORTUS

Stanislas Sawadogo*, Wendmanegda Edith Christiane Kouraogo, Pingrewendé Marcellin Ouedraogo, Anankpètinan Prosper Dabiré, Andouormwine Abel Somé, Dinanibè Kambiré

ABSTRACT

Haemonchus contortus is known to cause severe gastrointestinal parasitic infections in small ruminants. Despite their effectiveness, the available drug-based treatments exhibit shortcomings and are associated with unwanted side effects. This study was designed to improve parasite eradication in small ruminants by highlighting the efficacy of two medicinal plants, namely Chamaecrista nigricans and Tephrosia pedicellata. An acute toxicity study involving these plant extracts was conducted on NMRI mice in accordance with OECD Guideline 423 (2001). Their anthelmintic properties of the selected plants were determined using eggs and larvae from Haemonchus contortus harvested from coproscopy and coproculture, respectively. The ovicidal and larvicidal activity of the extracts was tested at a concentration of 1 mg/mL and compared to albendazole, the reference control. The acute toxicity study found that the lethal dose 50 (LD50) values for the extracts were beyond 5000 mg/kg body weight, thereby classifying them as low-toxicity plants. In vitro anthelmintic action revealed a significant inhibitory effect on the eggs and larvae of the parasite Haemonchus contortus comparatively to DMSO and the positive control (albendazole). Indeed, Chamaecrista nigricans and Tephrosia pedicellata were able to inhibit the eggs by 50.47% and 43.14%, respectively. Meanwhile, the larvae were inhibited by 87.92% and 92.49% by the aqueous extract of Chamaecrista nigricans and by 85.71% and 90.81% by that of Tephrosia pedicellata following 2 hours and 4 hours of incubation. These findings indicate that Chamaecrista nigricans and Tephrosia pedicellata are marginally toxic and possess anthelmintic properties against the parasite Haemonchus contortus. Therefore, these plants may be recommended to small ruminant farmers as a means of controlling gastrointestinal parasites.

Keywords: Haemonchus contortus, Chamaecrista nigricans, Tephrosia pedicellata, Anthelmintic Action, acute toxity.