فهرست مطالب masoumeh hayati

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.

Clostridium perfringens is an important anaerobic bacterium found in the intestine of some livestock. It is concerned with the etiology of some diseases including enterotoxaemia. Various diseases are caused by different types of C. perfringens. Nonetheless, there is no published research on molecular typing and distribution of this pathogenic microorganism in Fars province.

Accordingly, our study focused on the isolation and toxin typing of C. perfringens from sheep, cattle, and goats in different parts of Fars province by the culture and the polymerase chain reaction (PCR) method.

Approximately 459 fecal samples were collected and cultured on defined media for the isolation of C. perfringens. The confirmed isolates were genotyped by the PCR method using specific primers.

C. perfringens was isolated from 30.93% of the total samples. The results of toxin typing showed a total of 76 (54%), 13 (9%), 30 (21%), and 23 (16%) isolates as types A, B, C, and D, respectively.

Our results indicated that C. perfringens type A was the most common type in sheep, cattle, and goats while the lowest number of isolates belonged to type B. Finally, the isolation of C. perfringens and toxin typing increase our knowledge of the epidemiology of these diseases and can help in the vaccine industry and better controlling related diseases.

Pasteurella multocida exist commensally in respiratory track of a variety of wild and domestic animals. Serotypes A and D are responsible for pneumonia in goats and sheep, and Fimbriae, adhesions, capsule, toxin, iron uptake factor and outer membrane protein are its important virulence factors. The aim of this study was to design a multiplex PCR for fast and simultaneous detection of more important virulence factors of P. multocida isolated from sheep and goats as well as their capsular typing and identification.

Totally 500 nasal swabs were collected from the goats and sheeps suspected to respiratory signs of pasteurellasis. After isolation abd detection of P. multosida by biochemical examination, the bacteria were assayed by specific primers for identification of major important virulence factors and their capsular typing.

Capsular typing of the isolates by PCR showed two capsular types A, D with 83.8% and 6.4% prevalence, respectively. The results also showed that 23 (74.19%), 21 (67.74%), 21(67.74%) and 24(77.4%) of the isolates were positive for presence of toxA, hgbA, ptfA and ompH genes, respectively.

  The most isolated P. multocida from goat and sheep were toxigenic, and capsular type A was the most common isolates in the Fars province. The remarkable high prevalence of toxA and ompH among the afflicted sheep and goats may imply to important role of these genes in epidemiology and virulence of P. multocida. Furthermore the high prevalence of P. multocida typeA harbor toxA gene can be attributed to its important role in the respiratory infection.