Dracunculus insignis in ferrets: comparison of inoculation routes.

Three routes of inoculation were compared to determine the best method to infect ferrets with Dracunculus insignis. The traditional method of administering infected cyclops containing L3s through gavage was compared to intraperitoneal (i.p.) and subcutaneous (s.c.) inoculation of L3s. Ten of 18 (56%) gavaged ferrets became infected after receiving copepods containing approximately 100 L3s each; 44 adult worms were recovered from these 10 animals. Twenty-one of 28 (75%) animals inoculated with 50 L3s each became infected i.p.; 92 adult worms were recovered from the positive animals. Four of 5 (80%) ferrets given subcutaneous inoculations of 50 L3s became infected; only 6 worms were recovered from these 4 animals. Inoculation of larvae via the i.p. or s.c. route greatly simplifies the infection procedure and produces more consistent results. A simple procedure is described, which permits rapid recovery of L3s to be used in the i.p. or s.c. inoculations.