Recovery of nematodes from ruminants by migration from gastro-intestinal ingesta and mucosa gelled in agar: preliminary report.

When gastro-intestinal ingesta and mucosa containing larvae or adult Haemonchus contortus, Ostertagia circumcincta. Trichostrongylus colubriformis, Strongyloides papillosus, Nematodirus spathiger, Gaigeria pachyscelis, Oesophagostomum columbianum or Chabertia ovina were suspended in 0,75--1,00% agar gel and incubated in physiological saline, a mean of 93,6% of the helminths migrated from the agar-ingesta or agar-mucosa into the physiological saline. The lowest suitable concentration of agar was 0,85--0,90% for one batch of agar and 0,65% for another. Although most of the worms had migrated from the agar gel after 3--4 h of incubation, migration usually continued for longer than 7 h. While low concentrations of formalin partially inhibited migration from the gel, slightly more worms were recovered from agar containing 1% bile than from agar alone.