屠畜豚에서 toxoplasma의 분리와 分離株에 대한 病源性 시험

Isolation of toxoplasma from slaughtered pigs and its pathogenicity

This studies were attempted to isolate Toxoplasma from cardiac muscle of slaughtered pigs by feeding the muscle to cats, and by inoculation of the digested muscle into mice. A pathogenicity of some Toxoplasma strains originally isolated from the slaughtered pigs to growing pig was tested. 1. Cats(kitten) started to shed Toxoplasma oocysts from 4th -7th days after feeding the muscle tissues, and the oocyst shedding was continued for 4-14days(mean 7 days). The oocysts in the feces were unsporulated and spherical without a micropyle, residuum or color. Sporulation time was 2-4 days in the solution of 2% potassium dicromate at room temperature. 2. Toxoplasma cysts were detected on the paraffin sections of brain tissue in a few kittens. The cysts were spherical or ellipsoid, and contained a number of basophilic granules. 3. Tachyzoites and cysts were detected in a few mice inoculated with the digested muscle. The cysts in brain were spherical or ellipsoid, and contained basophilic granules. 4. Isolation rates of Toxoplasma from 160 pigs were 21.3 percent(34 cases) by using cat, and 5.6 percent(9 cases) by using mouse, respectively. 5. When some strains of Toxoplasma oocysts isolated from the slaughtered pigs were administered to healthy young pigs(50~80 days old), the principal clinical signs were fever, diarrhea, cough, incoordination and torticollis. 6. Gross lesions of the pigs, especially in the 50 days old, were edema of lungs, increasing in quantity of peritoneal and pleural fluids, enlargement of lymphnodes, and pseudomembrane formation in the small intestine. 7. The pigs revealed microscopically, multiple focal necrosis of liver, infilteration in enlarged alveolar walls, diffuse necrosis of lymphnodes, necrosis of intestinal mucosa and infilteration in lamina propria, glialnodules and perivascular cuffings in brain, and focal necrosis and decrease in number of lymphocytes of spleen.