Congenital trichinellosis in experimentally infected mice.

The present study aimed at allocating the time during pregnancy at which transplacental transmission of Trichinella spiralis (T. spiralis) larvae took place. Swiss albino mice were infected at different durations of pregnancy; five days before mating, on gestation day zero and five days after mating. Furthermore, to study the effect of immunosuppression on transplacental transmission, half of the experimental mice were immunosuppressed using cyclophosphamide drug (Endoxan). The percentage of infected uteri, embryos and placentas and the mean larval count were calculated on day 8 post infection (PI). Moreover, the percentage of infected offspring and the mean larval count in their muscles were estimated on day 30 PI. The results of the present study revealed that, transplacental transmission of T. spiralis could occur in offspring of mice when their mothers are infected before or after pregnancy. This was documented by the presence of larvae in the muscles of offspring. However, the rate of this transmission increased when the mothers are infected at late pregnancy whether they were immunosuppressed or not. The administration of the immunosuppressive drug whether before or after pregnancy increased the rate of infection and the mean larval count in both uteri of mothers and muscles of their offspring. A higher percentage of abortion was demonstrated in females infected before mating in different studied groups.