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This paper analyzes the effects of the infection caused by Toxoplasma gondii on the cat duodenal wall. Six cats (Felis catus) with 3-month-old were randomly divided into Control Group (G1; n = 3) and Infected Group (G2; n = 3). The animals from G2 received orarilly 200 T. gondii tissye cysts of ME49-strain (type II). After 40 days, the animals were submitted to euthanasia, laparotomy and had their duodenum removed, fixed in Bouin solution and submitted to histological routine obtaining 3 μm transverse cuts. The cuts were stained with Hematoxylin-Eosin (HE), Azan, Periodic acid-Schiff (PAS), Alcian-Blue, and Mallory trichrome. Qualitative assessment of the intestine wall as well as comparative measurements with respect to the thickness of mucosa, muscle tunic, total wall, the height of the villous, the depth of the crypts, and the height of the enterocytes and their nuclei were carried out. Calciform cells, the intraepithelial lymphocytes, and the Paneth cells were quantified. The results showed that the infection led to the atrophy of the mucosa, muscle tunic, and the intestinal wall of the duodenum of G2 cats (p < 0.05). The enterocytes height presented significant (p < 0.05) increase for G2 animals. According to the qualitative analysis, the collagen fibers were visibly taken a broader area on the intestinal wall layers, what suggests they have increased in size. Decrease in the sulphomucins secretion and the increase of Paneth cells were observed for these animals (p < 0.05).

The efficacy of azithromycin and pyrimethamine in experimental infection of mice with Toxoplasma gondii was tested. Daily dosages of 200 mg/kg and 12.5 mg/kg, respectively, were given orally over a period of ten days. The medications were administered in combination or separately. The combined use of the drugs yielded better results, and a similar investigation using a cystogenic strain of the parasite will be conducted in a future study.

Unlabelled: Peritoneal exudates and organs from 53 male albino mice, experimentally infected by Toxoplasma gondii were studied, 21 at the acute phase of infection, and 32 at the chronic phase. Peritoneal inoculations were made with 0.5 ml of peritoneal exudates (tachyzoites), or brain macerates (cysts) of previously infected mice. Direct examinations of peritoneal exudates (tachyzoites) were realized between 3 to 12 days post-inoculation, and in brain (cysts) after 10 days post-inoculation . Organs macerates were inoculated in new mice, for the parasite recovering, from exudates or from brains. At the acute infection (3 to 12 days) the positivity at the direct examination was: peritoneal exudate 19/19, lung 12/14, muscle 6/9, heart 4/9 and brain 1/3. After inoculation: peritoneal exudate 5/5, heart 9/9, lung 13/13, muscles 14/17 and brain 2/2. Then, there were 9 new positive organs. At the chronic infection, between 10 and 495 days, the positivity was, at direct examination: brain 28/32, heart 0/4 and muscle 0/4. After inoculation: brain 6/6, heart 14/29 and muscle 16/26. After that a new positive mouse was detected, which leads to 29 the positivity for all mice, or 90.6%. Finally the positivity for the acute phase was: peritoneal exudate 19/19 (100%), heart 15/17 (88.5%), muscle 12/14 (85.7%), lung 14/14 (100%) and brain 2/3 (66.6%). For the chronic phase: brain 28/32 (87.5%), muscle 16/28 (57.1%) and heart 14/31 (45.1%). At the end of experience, at the 495th day, the brain still presented large cysts by direct examination and also the heart and muscle were positives after inoculation., Conclusions: 1st) on mice the Toxoplasma gondii remained for 495 days, mainly on the brain, but also on heart and muscle.(ABSTRACT TRUNCATED AT 250 WORDS)