Experimental Trichinella spiralis infection in sheep.

During susceptibility studies of non-specific hosts, three merino sheep were infected with 3000, 5000 or 7000 Trichinella spiralis larvae by gavage. Clinical, physiological and serological parameters were assessed during the experiment. On the 152nd day p.i., animals were necropsied and, using artificial digestion methods, numbers of Trichinella larvae in muscle tissues were determined. The most infected parts were masseters with 3122 larvae g-1 muscle, 5526 larvae g-1 muscle and 4058 larvae g-1 muscle and diaphragms with 2778 larvae g-1 muscle, 2725 larvae g-1 muscle and 2320 larvae g-1 muscle, for the 3000, 5000 and 7000 infection levels, respectively. A positive correlation between infective rate and circulating antibodies was observed using ELISA and latex agglutination (LA) test methods. Trichinella larvae from sheep applied by gavage to ICR mice developed to the muscle stage. No significant changes were found in the clinical and physiological parameters of infected animals. Our results confirm the high susceptibility of merino sheep to T. spiralis infection.