Abstract:
Forty four Balb C mice, aged 18 weeks were infected with crocodile ( Crocodylus
niloticus)-derived Trichinella species. Of the infected mice, 32 were
randomly divided into two groups each containing equal numbers of males
and females; levamisole treated group and fenbendazole treated group.
Each group was randomly subdivided into two subgroups as follows:
levamisole group (subgroup 1: treated with levamisole on day 35 post
infection and subgroup 2: treated with levamisole on days 35 and 42 post
infection) and fenbendazole group (subgroup 1: treated with fenbendazole
on day 35 post infection and subgroup 2: treated with fenbendazole on
days 35 and 42 post infection). The first sub-groups treated on day 35
post infection were slaughtered on day 42 post infection and the second
subgroups were treated on days 35 and 42 post infection and slaughtered
on day 49 post infection. Two female mice were infected a day after
mating and were slaughtered together with the offspring on day 64
post-infection. Ten infected control mice were given 1 ml distilled
water orally as placebo, and five of these were slaughtered on day 42 post
infection. The results showed that the mean reproductive capacity index
of this strain (RCI) in Balb C mice was 110. There was a significant
reduction ( P<0.01) in larval counts in the single treatment groups (day
35) and in the double treatment groups (days 35 and 42) for both
anthelmintics when compared the number of parasites in the control
groups. After a single treatment, levamisole reduced the infection by
79.9% and fenbendazole by 76.7%. Following double treatments, levamisole
reduced the infection by 95.5% and fenbendazole by 99.1%. There was
evidence that the infected pregnant mice transmitted the parasite to
their offspring. It is not certain whether the parasite was transmitted
congenitally or transmammary. Alternative ways of controlling the
parasite in crocodile farms in Zimbabwe are discussed.
