(Figs. 3 and 4) were substantially

(Figs. 3 and 4) were substantially lower than those employed in the EHT and AMT (Fig. 2). According to the LC50 and LC95, the LDT was a more sensitive test than the others. Comparing Figs. 3 and 4, the LC95 was significantly lower in the LDT than in the LFIT and the curve shifted to the left since the concentration of 0.06mg/mL of A. sisalana extract showed 91.8% inhibition of larval development compared to 0% in the LFIT. On the other hand, in the LDT and LFIT,
the inhibition reached 100% at the same concentration of 0.12mg/mL (Tables 2 and 3). In a real situation, the L1 stage will be found in the stools. So, if part of the A. sisalana extract passes through the animal’s gastrointestinal system, this material can have a significant effect on the parasites in the feces. Maybe the action on the eggs in stools cannot occur, since according to the in vitro tests more than 30 mg/mL is necessary to completely inhibit egg hatching (Table 1)
and for the adult parasites, the concentration necessary is 75 mg/mL (Table 4).
However, the action on L1 is an interesting approach because it can drastically reduce the pasture contamination as well as the herd infection. L1 and L2 larvae only have one cuticle and spend at least seven days feeding in the stools. These factors should be further investigated in themedicinal herb experiments, to look for a delayed effect. Substances from plants can have action in feces when they are not destroyed ormodified by the ruminant digestive system.