EFFECT OF TIME ON MIGRATION OF OESOPHAGOSTOMUM SPP. AND HYOSTRONGYLUS-RUBIDUS OUT OF AGAR-GEL

The agar-gel migration technique has previously been described, howeve r, aspects regarding the effect of timing on worm migration needed fur ther scrutiny. In the first experiment, pigs inoculated with Oesophago stomum dentatum were slaughtered simultaneously and their intestines s tored at 21-33 degrees C until processed pairwise 2, 4, 6, 8, 12 and 1 8 h after slaughter, More than 95% of the worms migrated out of the ag ar if processed within 6 h, In the second experiment. intestines were treated immediately after slaughter and the migratory speed of adult w orms or 4th-stage larvae of O. dentatum or O. quadrispinulatum, or adu lt Hyostrongylus rubidus were studied. For both Oesophagostomum specie s, more than 90% of the worms were recovered within 1 h. H. rubidus wa s significantly slower; however, approximately 98% of the worms had mi grated out of the agar-gel by 20 h. This information is essential in p lanning experiments where recovery of live worms is of value.