Infectivity, reproductive capacity and distribution of Trichinella spiralis and T. pseudospiralis larvae in experimentally infected sheep.

Twelve Merino sheep were experimentally shown to be susceptible to infection with Trichinella spiralis or T. pseudospiralis by feeding on infected carcasses of mice or by oral intubation with recovered muscle larvae. The larvae recovered from the sheep showed variable tissue distribution. The diaphragm and tongue were most affected. The viability of the recovered larvae was confirmed by successful passage in mice. The reproductive capacity of T. spiralis in sheep was higher than that of T. pseudospiralis, and also higher than its reproductive capacity in C57BL/6J mice. The reproductive capacity of T. pseudospiralis in sheep at a lower dose was higher than that observed in mice. However at higher doses, it was significantly lower than that in mice. Therefore, it may be concluded that the sheep may be considered a suitable host for both species of Trichinella.