The effect of Trichinella spiralis on muscular activity of experimentally infected mice

Nematodes of genus Trichinella are wide-spread zoonotic parasites, able to infect a large variety of vertebrates. Animal hosts are usually regarded as asymptomatic carriers. However, there is little data regarding the functional consequences that T. spiralis infection renders on muscle cells. The aim of the present study was to assess the effect of T. spiralis on the effort capacity of experimentally infected mice. Overall, 60 mice, divided into three groups were used: M (uninfected), L200 and L1000, infected with 200 or 1000 larvae/mouse respectively. The mice were periodically weighed and their effort capacity was evaluated (days 0, 7, 15, 35 and 60). From each group, two randomly selected mice were euthanized after evaluation carcasses were artificially digested in order to establish the number of larvae per gram (LPG). On day 0, there were no significant differences among groups. Starting with day 7, the effort capacity of infected groups decreased, with significant differences between group M and the infected groups. From day 15, the differences between the infected groups also became significant. The LPG gradually increased and the differences between groups were always significant. A strong correlation between the LPG and decreased effort capacity was noted. The present study demonstrates the reduction of muscular capacity in mice experimentally infected with Trichinella spiralis, in correlation with the infective dose, providing new insights in this parasite's transmission strategy.