Name: Tovuu Amgalanbaatar
Affiliation: Research Unit for Advanced Preventive Medicine
Position: Foreign Visiting Researcher
Term: September 2022 – February 2023
Host researcher: Assistant Prof. Keisuke Suganuma (English /Japanese)
Circumstances of application:
I was a research team member in the SATREPS project titled “Epidemiological Studies on Animal Protozoan Diseases in Mongolia and Development of Effective Diagnostics Measures (2014-2018)” which is implemented in OUAVM and IVM. My research work is to determine the infection progress of dourine occurring in Mongolian horse herds. In the frame of this research, isolated culture-adapted T. equiperdum strain IVM-t1 strain was experimentally infected into authentic hosts (horses). The infection progress was measured by several times post infection by using following methods, such as PCR, ELISA, ICT, and microscope screening.
Research activity in NRCPD:
Dourine is caused by a protozoan parasite named T. equiperdum, and was first reported in Mongolia in 2003 by a serological survey and its prevalence was 5.5%. In 2018, we conducted a serological survey using a recombinant antigen-based ELISA in a total of 4794 horses in Mongolia and its prevalence was 10.3%. By the way, in the frame of SATREPS project which was implemented in Mongolia between 2014-2018, we have successfully isolated a pure culture of T. equiperdum named “T. equiperdum strain IVM-t1” from Mongolian natural infected horse and the parasite culture is still maintaining in IVM and NRCPD. I made an experimental infection by T. equiperdum strain IVM-t1 in the horses and studies the infection progress. Also, we designed new primer sets to determine only T. equiperdum infection in horse.
We have selected three female horses for the present experimental infection study, which were apparently healthy and tested as negative by PCR assay. We made an experimental infection in three horses with T. equiperdum strain IVM-t1 isolate culture in different ways, including vein and vagina. After two days the post infection, I have 11 times measure the horses’ basic physiological parameters, and collected the horses’ samples such as blood, serum, milk and genital organ’s swab samples and prepared thin blood smears, and extracted DNA from blood, swab and milk samples. The extracted DNA was analyzed by PCR assay using the parasite specific primers, and thin blood smears were checked by light microscope, respectively. Only one horse named group-3 (Brown mare) was made the experimental infection with dilution of the parasite 1х105 by vein is showed some clinical signs and diagnosed as positive. For general blood parameters, the number of white cells has increased from 10th day post-infection. This means that inflammation has already developed in the horse. As for the PCR assay in blood samples, the positive bands have detected from the third day of post-infection in the horse. But no detected any positives from swab samples in this horse. Antibody titer has increased a little in the horse from 14th days of post infection was detected by ELISA test. But not detected any positive by ICT test. The antibody titer which against the parasite was increased a little in the horse’s serum from 14th days of post infection was detected by ELISA test. But not detected any positive by ICT test and blood smear.
Future prospects:
I am planning to continue the present experimental infections as more big scale, including at least 10 horses, changing parasite numbers to infect and other factors such as to use splenectomized horse. In the frame of this short time, foreign research study I have gained many study skills, knowledge and also, I have got many friends globally. Of course, I am going to be happy to share my obtained study skills and other knowledge with my laboratory colleagues, specially to young researchers. I would like to express my deep gratitude to my supervisor Asst. Prof. Keisuke Suganuma, and Prof. Inoue for their great help and support. Also, I wish to express my thanks to all members of NRCPD for their kind support in my research.