Collection of Parascaris spp.

Collection of live worm specimens at necropsy occurred as previously described (Scare et al., 2018). Brief details are provided in the Supplementary files. For Part 2 of this study (see Fig. 1), additional worm specimens for in situ controls were obtained by leaving numerous worms within a 30 cm section of the jejunum. Intestinal content was allowed to remain in the segment and both ends were tied shut with string. The segment was placed in a closed container and then into the water bath to maintain its temperature at 37 °C. The purpose of the in situ controls was to mimic the natural environment of the worms while minimizing disturbances. Therefore, this in situ control was used as a comparison for the in vitro non-drug-treated controls.