Serology and histopathology of taxoplasma gondii infection in Mus musculus (Linnaeus) experimentally exposed to the parasites obtained from chronically-infected Rattus norvegicus (Berkenhout) and Rattus rattus mindanensis (mearns) caught in Dasmariñas, Cavite, Philippines

• Main Author: Salibay, Cristina Cabanacan
• Format: Text
• Language: English
• Published: Animo Repository 2004
• Subjects: Serology; Parasites; Histology; Pathological; Infection; Biology; Rattus rattus
• Online Access: https://animorepository.dlsu.edu.ph/etd_doctoral/1198; https://animorepository.dlsu.edu.ph/cgi/viewcontent.cgi?article=2199&context=etd_doctoral

Rattus norvegicus and Rattus rattus mindanensis caught in agricultural (AGR), commercial (COM), and residential (RES) sites in Dasmariñas, Cavite, Philippines were serologically assayed for anti-T. gondii antibodies (Abs) using the TOXOCELL AD direct agglutination test kit (BIOKIT S.A. Manufacturing Company, Barcelona, Spain). Fifty eight percent (58.0%) of R. norvegicus and 42.0% of R. r. mindanensis were seropositive (sero+). Infection was higher in male rats, and those caught in the commercial site had 100.0% seropositivity. Thirty percent (30.0%) of the R. norvegicus and 51.0% R. rattus mindanensis had acute infection. Seventy percent (70.0%) of the R. norvegicus and 49.0% of R. rattus mindanensis were chronically infected with Abs titre 1:256-1:2048 and 1:256-1024, respectively. The association between the presence of infection with the rat gender and species and their collection sites was insignificant (p>0.05). Mice inoculated with different dosages (0.5-1.0ml BTH+) prepared from T. gondii chronically-infected rats were monitored for four weeks post-exposure (PE), and the histopathology in the lungs, liver, spleen, heart, diaphragm and brain was evaluated. Ninety three (=64.0%) of BTH+-inoculated mice were sero+. Seropositivity was significant (p≤0.05) in mice exposed to 0.75-1.0ml BTH+. Regardless of the rat species used as source of BTH+, seropositivity was significantly lower (p≤0.05) in BTH+/RES-inoculated mice relative to those exposed to BTH+/AGR and COM. Weight change per week in sero+ mice was significantly lower (p≤0.01) compared to seronegative (sero-) and control mice. Percent mortality was 11.0% in sero+ mice. Tissue damage was observed in the lungs, liver, spleen, heart, diaphragm, and brain starting Wk-1 PE. Regardless of the source of BTH+ and inoculum dose, inflammatory cell infiltration, vasculitis and blood vessel congestion and dilatation were consistently manifested in the tissues examined. Severity of damage was more pronounced in the lungs and liver than the other tissues ...