MORPHOMETRIC ANALYSIS AND VIRULENCE OF ISOLATES OF TOXOPLASMA GONDII RECOVERED FROM PREGNANT AND NEWBORN MICE IN GOIÂNIA-GO

Abstract

Studies in Toxoplasma gondii carried out in newborns are interesting and relevant as they induce serious lesions in newborns when they are not properly treated. Three isolates of Toxoplasma gondii in newborns and the RH strain were assessed regarding pathogenicity and virulence in Balb-c albino mice. Tachizoite suspension used in experimental tests was obtained through punction or lavage from the peritoneal cavity in mice presenting with ascites. Each sample was inoculated in groups of four mice with inoculates of 10 1 , 10 2 , 10 3 , 10 4 , 10 5 , 10 6 alive tachyzoites, via intra peritoneum. We found that isolates 15, 20 and RH strain behaved lethally to mice. Isolate-3 behaved lethally in all mice up to 10 5 tachyzoites. Death of all animals that presented acute infection occurred 5-10 days following inoculation. Isolate-15, isolate-20 and RH strain presented a greater diameter and minor areas as compared with isolate-3. We found that the most virulent isolate also demonstrated greater area and diameter and these findings reinforces the hypotheses that besides behavioral differences and genetic variations, morphological variations also exist when different strains of T. gondii are evaluated.