Anticoccidial Effects of Ageratum conyzoides (Asteraceae) and Vernonia amygdalina (Asteraceae) Leaves Extracts on Broiler Chickens

Avian coccidiosis is a parasitic disease which causes a considerable economic loss in poultry. The emergence of anticoccidial drug resistance enhances the need for the development of the novel approach and alternative controls strategies such as plants extracts. Therefore, this study was conducted to evaluate the anticoccidial efficacy of ethanolic extracts of Ageratum conyzoides and Vernonia amygdalina on broiler chickens. Ninety (90) Cobb 500 broiler chickens were divided into nine groups of 10 chickens each. Each chicken in 8 groups (A-H) was orally infected with approximately 3000 sporulated oocysts of Eimeria tenella at day 28 of age while one group (group I) served as uninfected control. After the establishment of the disease at day 7 post-infection, chicks of groups A to F were treated with the graded concentrations (1.5, 3 and 6 g/ L) of ethanolic extracts of both plants. Group G was treated with the conventional drug (Anticox) and group H served as infected non treated control. All treatments were mixed with drinking water and administered for five consecutive days. The activity was evaluated by means of faecal oocyst count reduction, host growth and haematological parameters. The results showed that ethanolic extracts of both plants demonstrated a gradual inhibitory effect on the shedding of oocysts in a concentration-dependent manner. Among the treated groups, the highest inhibitory effect was recorded in the extract concentration of 6 g/L (oocyst count reduction rate of 100% which was comparable to the group receiving conventional drug (P>0.05). There were no significant differences in the food intake between experimental groups (P>0.05). The mean body weight of treated groups was significantly (P<0.05) higher than that of the untreated group. All treated groups showed better feed conversion ratio (FCR) as compared to infected non-treated group (P<0.05). The mean of RBC count, Hb rate and PCV after treatment with the various concentrations of ethanolic extracts of both plants was significantly (P<0.05) higher than those of the untreated group. These results demonstrated that both plants have similar activity and could, therefore, find application in anticoccidial therapy.