The article is devoted to the current problem of differential diagnosis of diseases of viral etiology in farm animals. Viral diseases are currently widespread, occupy a leading role in the infectious pathology of farm animals, causing enormous economic damage. Given the magnitude of animal vaccine prophylaxis, in order to increase the effectiveness of antiepizootic measures, the urgent issue i s the development of methods for the rapid and effective detection and differentiation of field and vaccine strains of the infectious rhinotracheitis virus in cattle. The possibility of using a polymerase chain reaction to identify and differentiate a vacc ine strain from epizootic strains and isolators of the cattle infectious rhinotracheitis virus is considered. In the process of research, a PCR-RFLP analysis method was developed to detect the IRT virus in the test material. The PCRRFLP analysis method was used to identify and differentiate the vaccine strain TK-A form epizootic strains and isolators of the cattle IRT virus. The principle of PCR, based on repeated repetition of DNA cycles, annealing and synthesis, which leads to an increase in the number of specific DNA fragments of the pathogen, allows you to take into account the results of PCR in an agarose gel. Analysis time is about 30 hours. The sensitivity of detecting viral DNA is 1-10 picograms (102 TCD). Due to characteristics such as relative simplicity and reaction rate, high sensitivity, specificity and reproducibility, PCR has recently become widespread in basic and applied research in various fields of biological science, including veterinary virology. The results obtained during the studies show that the use of PCR-RFLP allows to differentiate field and vaccine strains and isolates of the IRT virus with a high degree of reliability. The use of PCR -RFLP analysis increases the efficiency and informativeness of studies in the molecular epizootol ogy of cattle RTI, as it allows not only to identify the DNA of different virus strains regardless of their nature, but also to differentiate between them, including differentiating the strain TK-A used for the production of attenuated vaccines against epizootic strains and isolates of the virus.

Main problem: The article highlights the problem of tests as methods of psychology, the influence of validity and reliability on the results of psychological research. Purpose: Uncovering the significance of validity and reliability on psychological research results. Results and their significance: Testing is an important method in psychology, allowing measuring various aspects of the psyche and behavior of a person. The history of the development of tests in psychology goes back more than a century and began with the work of Francis Galton and Alfred Binet. Over time, the tests have become widely used in various fields such as education, personnel selection, clinical diagnosis and research. Basic requirements for tests include reliability (repeatability of results), validity (measurement accuracy), standardization (same test conditions) and objectivity (lack of subjectivity in assessment). Tests must be designed using psychometric principles to ensure accuracy and validity of results. Modern tests include a variety of measurement techniques, such as tests of personality, intelligence, aptitude, and professional skills. The use of tests in psychology requires professional training to correctly interpret the results and make valid conclusions. Testing as a method of psychology continues to evolve, and its role remains key in the study of the human psyche and behavior. Testing in psychology has a wide range of applications, including assessing personality traits, identifying psychological disorders, and predicting behavior and success in various areas of life. The development of computer-based tests and online platforms makes testing more efficient and convenient for researchers and participants. Modern tests increasingly take into account cultural differences and the diversity of individual characteristics, which contributes to more accurate and tailored assessments. It is important to remember that the use of tests requires ethics, confidentiality and compliance to ensure the reliability and validity of the data obtained.