Evaluation of the immunogenicity of Toxoplasma gondii attenuated strain in cats

Background &

Toxoplasma gondii is a parasite which definitive hosts, Felid and cats, play a critical role in transmission and distribution of the parasite and their immunization is a proper way to control the infection. The aim of the present study is to evaluate the                       immunogenicity of Toxoplasma gondii attenuated isolate produced in Razi Institute branch of    Shiraz in catsMaterials &

Twelve male DSH (Domestic short hair) kittens aged 3-6 months were  randomly divided into three groups; each contains four cats. The First group received tachyzoites of Toxoplasma gondii attenuated isolate at a dose of 10×106 by injection, the second group         received a dose of 25×106 orally and the last group received culture medium as a control. The  humoral immune responses and Cellular immunity evaluated by modified agglutination and skin test. One month after immunization, all cats were challenged by Toxoplasma's PRU strain, after which the cats' feces were collected and molecular tests were performed for five days.

The results of modified agglutination and skin test showed that administration of oral and injection vaccine had a significant increase in comparison with control. Also, Molecular testing after challenge revealed that immunization of cats by oral and injection way of Toxoplasma gondii attenuated isolate could successfully prohibit oocysts shedding in cats.

In order to the significant immune responses and prevention of oocysts shedding, it is suggested that, using this isolation of Toxoplasma gondii as a possible candidate vaccine for cats in future studies.