4 Veterinary Medicine International Table 2: Mean mortality rate of Heligmosomoides bakeri L1 and L2 larvae incubated in increasing concentrations (mg·mL−1) of aqueous and ethanolic extracts of Ageratum conyzoides compared to Mebendazole. Larval stages Treatment L1 larvae L2 larvae NA: not applicable. Aqueous extract Ethanolic extract Mebendazole Aqueous extract Ethanolic extract Mebendazole Negative controls Distilled water 5% tween 3.5 ± 5.0 3.0 ± 4.8 3.5 ± 5.0 3.5 ± 5.0 3.0 ± 4.8 3.5 ± 5.0 0.625 6.0 ± 5.1 6.7 ± 4.5 33.8 ± 21.1 32.6 ± 20.34 13.6 ± 7.0 77.0 ± 3.5 Tested concentrations (mg·mL−1) 1.25 2.5 8.1 ± 1.0 32.3 ± 12.4 60.7 ± 6.8 96.3 ± 4.8 32.2 ± 12.4 89.4 ± 7.4 40.8 ± 15.0 50.1 ± 13.1 32.5 ± 4.2 35.4 ± 29.0 86.7 ± 5.2 96.0 ± 0.8 3.75 55.0 ± 22.3 99.4 ± 1.2 84.4 ± 3.8 58.2 ± 20.0 95.5 ± 5.2 100.0 ± 0.0 oil aspect in this work. 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