Abstract. Twenty-four 5-month-old battery-hatched Japanese quail were inoculated orally with 10 5

Fourteen 2-3-wk-old turkeys were inoculated orally with 10(5) or 10(4) infective oocysts of the ME 49 strain of Toxoplasma gondii. Of the 8 turkeys given 10(5) oocysts in experiment 1, 3 died or were killed 12 or 14 days after inoculation (DAI) because of respiratory distress associated with a concomitant Aspergillus-like fungus infection. The remaining 5 turkeys remained normal and were killed 62 DAI. Toxoplasma gondii was isolated in mice from the heart of all 5, from the breast muscles of 2, leg muscles of 3, and from the brains and livers of none of the turkeys. All 6 turkeys fed 10(4) oocysts in experiment 2 remained clinically normal until necropsy on 41 DAI; T. gondii was isolated from pooled tissues from each turkey. All 14 turkeys developed high antibody titers to T. gondii in the modified agglutination test (MAT) using formalinized tachyzoites. The enzyme-linked immunosorbent assay (ELISA) was as sensitive as MAT for detecting T. gondii antibodies in turkey sera. The latex agglutination and indirect hemagglutination tests were less sensitive than the MAT and ELISA. No dye-test-measurable antibodies were found in sera of any turkey.

The prevalence, size, genome, and life cycle of Eimeria acervulina make this organism a good surrogate for Cyclospora cayetanensis, a protozoan that causes gastroenteritis in humans, including recent outbreaks in the United States and Canada associated with contaminated raspberries and basil. Laboratory studies of C. cayetanensis are difficult because of the lack of readily available oocysts and of infection models and assays. UV radiation and high-hydrostatic-pressure processing (HPP) are both safe technologies with potential for use on fresh produce. Raspberries and basil were inoculated with sporulated E. acervulina oocysts at high (10(6) oocysts) and low (10(4) oocysts) levels, and inoculated and control produce were treated with UV (up to 261 mW/cm2) or HPP (550 MPa at 40 degrees C for 2 min). Oocysts recovered from produce were fed to 3-week-old broiler chickens, which were scored for weight gain, oocyst shedding, and lesions at 6 days postinoculation. Oocysts exhibited enhanced excystation on raspberries but not on basil. Birds fed oocysts from UV-treated raspberries had reduced infection rates, which varied with oocyst inoculum level and UV intensity. Birds fed oocysts from UV-treated raspberries (10(4) oocysts) were asymptomatic but shed oocysts, and birds fed oocysts from UV-treated basil (10(4) oocysts) were asymptomatic and did not shed oocysts. Birds fed oocysts from HPP-treated raspberries and basil were asymptomatic and did not shed oocysts. These results suggest that UV radiation and HPP may be used to reduce the risk for cyclosporiasis infection associated with produce. Both treatments yielded healthy animals; however, HPP was more effective, as indicated by results for produce with higher contamination levels.

Sixteen 6-mo-old battery-reared ring-necked pheasants (Phasianus colchicus) were inoculated orally with 10(5) (group A, ME 49 strain, five birds), 10(4) (group B, ME 49 strain, six birds) and 10(4) (group C, GT-1 strain, five birds) Toxoplasma gondii oocysts. The pheasants in groups A and B remained clinically normal. One of the pheasants in group C died 19 days after inoculation (DAI); T. gondii was found in histological sections of brain and heart and encephalitis, myocarditis and enteritis were the main lesions. Toxoplasma gondii was isolated by bioassays from pooled tissues of five of six pheasants in group B killed 36 DAI. Toxoplasma gondii was isolated from the brains, hearts and skeletal muscles of each of the four pheasants inoculated with the GT-1 strain (group C), and from the brains of four, hearts of three and skeletal muscles of four of five pheasants inoculated with the ME 49 strain (group A). All pheasants developed high (1: 1,600-1:25,600) antibody titers to T. gondii in the modified agglutination test (MAT) 36 to 68 DAI. Antibody titers detected with the MAT were higher than those detected in the indirect hemagglutination and latex agglutination tests. Antibodies were not detected in 1:4 dilution of pheasant sera with the Sabin-Feldman dye test.