Abstract

The migration and distribution pattern of spargana in mouse body was observed after experimental infection through mouth. The spargana were obtained from the snake, Natrix tigrina lateralis, caught in Hoengseong-gun, Kangwon-do. A total of 28 male mice (ICR strain), 21-25g in body weight, were fed each with 5 scolices (and necks) of spargana and killed after 10 minutes to 14 days. Systemic autopsy was performed on each mouse to recover the spargana. The results are as follows: The spargana were found to penetrate into the stomach or duodenal wall of mice as early as 10 minutes after infection. They completed the penetration within 30 minutes and appeared in abdominal cavity. It was observed that spargana did not migrate tangentially along the gut wall but directly perforated the wall. After 1 hour to 1 day the majority of spargana distributed in abdominal cavity of mice except few which migrated to muscles or subcutaneous tissues. It was within 7 days that nearly all of the spargana migrated to subcutaneous tissues. Out of total 28 in number found from subcutaneous tissues, 13 distributed around neck region, 12 around trunk and other 3 on head of mice and the most common sites were submandibular and subscapular areas. There was nearly no host tissue reaction to migrating spargana. The initial length of spargana given was 4 mm in average but it increased to 12 mm after 7 days and to 35 mm after 14 days. The results suggest that spargana orally given to mice penetrate the gut wall within 30 minutes followed by escaping into abdominal cavity, and after passing through thoracic cavity or abdominal wall they finally localize in subcutaneous tissues chiefly around neck region within 7 days.