Effect of Thiabendazole Upon Experimental Trichinosis in Swine

Summary Pigs fed a diet containing 0.1% thiabendazole and exposed to larvae of T. spiralis developed either no infection or an infection of negligible severity. A concentration of 0.01% thiabendazole in the diet did not prevent pigs from acquiring trichinosis, but no mortality occurred when the pigs were exposed to huge numbers of Trichinella larvae during the period of medication. A moderate experimental infection of trichinosis was not eradicated by feeding 0.15% thiabendazole for 7 days, beginning on 5th day of infection. Pigs fed 0.3% thiabendazole for 7 days, beginning 2 or 4 weeks after exposure to massive infections, suffered no mortality, while 4 of 6 untreated pigs died. The data further indicate that the majority of the Trichinella larvae in the muscles of the treated pigs were killed by the medication employed.