The Probable Explanation for the Difference in the Localization of Adult Trichinella spiralis in Young and Old Mice

Abstract

In young mice significantly greater numbers of adult T. spiralis were found in the posterior half of the small intestine (avg.: 69.5%), while the reverse was true in old mice (avg.: 18.7%). Approx. the same percentage development of adult worms was found in mice of both age groups, showing no evidence of age resistance. A reversal in distribution was shown in young mice by artificially decreasing their intestinal emptying time with morphine sulphate. In this case approximately 95% of the worms were located in the anterior half of the small intestine.