Abstract. The aim of the study was to study the practical value of the PCR method for the identification of chlamydia species in cattle. Methods. PCR diagnostics of biological material from cows and calves was carried out. Results. In the course of laboratory studies, it was found that in 17.1 % of cases the biological diversity of the chlamydia species was found in the biological material: the genomes of Chlamydia spp. (7.6 %), Chlamydophila pecorum (7.6 %) and Chlamydophila abortus (1.9 %). Specific DNA regions of the bacterium Chlamydophila pecorum were found in biological material from calves in 1.9 % of cases. The examined calves were found to have an acute form of chlamydial infection with respiratory damage, as well as keratoconjunctivitis. Chlamydophila abortus genomes were identified in biomaterials in 6.7 % of aborted cows, which confirmed the presence of latent and chronic chlamydial infection of the reproductive tract in them. Samples positive for Chlamydia spp. DNA of Staphilococcus aureus was detected (37.5 %). Scientific novelty. Currently, PCR diagnostics of bacteria of the genus Chlamydophila, which have a unique cycle of development of intracellular parasites, open up new opportunities for detecting the genetic material of the Chlamydia species in farm animals. The polymerase chain reaction method turned out to be highly sensitive and specific for the diagnosis of chlamydophiles in farm animals with acute, latent, asymptomatic and chronic forms of the course of the infectious process. The difficulty in identifying pathogens with close genetic links (Chlamydophila psittaci, Chlamydophila abortus and Chlamydophila picorum) is determined by the quality of laboratory and diagnostic tools.
cattle, infectious diseases, chlamydia, PCR method, genetic diversity, genomes, DNA, diagnostics.
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