BIOLOGICAL PROPERTIES OF FUSOBACTERIUM NECROPHORUM ISOLATED FROM INFECTED CATTLE TISSUES IN ALMATY REGION
Authors:   Doctor of Veterinary Sciences, Academician of the National Academy of Sciences of the Republic of Kazakhstan, Chief Researcher of LLP «Kazakh scientific-research veterinary institute», Almaty, Kazakhstan, Ivanov N.P. ,   akademikvet@mail.ru,   0000-0003-1964-241X, Egorova N.N. ,   Candidate of Veterinary Sciences, Senior Researcher of LLP «Kazakh scientific-research veterinary institute», Almaty, Kazakhstan; natalya-egorova60@mail.ru; 0000-0001-9525-1854, Sarimbekova S.N. ,   , Master of Veterinary Science, Almaty, Kazakhstan; sarimbekova@yandex.kz; 0000-0002-9625-5467, Sushi V.Yu ,   Candidate of Veterinary Sciences, Leading Researcher of LLP «Kazakh scientific-research veterinary institute», Almaty, Kazakhstan; vladasali@mail.ru; 0000-0002-3520-2257, Ilimbayeva A.K. ,   Junior Researcher of LLP «Kazakh scientific-research veterinary institute», Almaty, Kazakhstan; almira577@mail.ru; 0000-0002-9847-564X
Published: October 2020

Necrobacteriosis (necrobacteriosis) is established as an infectious disease characterized by purulent-necrotic lesions of tissues mainly of the lower parts of the extremities, especially in the area of the corolla, and in some cases in the oral cavity, on the udder, in the genitals, liver, lungs and other tissues and organs. Many animal species are affected by necrobacteriosis. The most susceptible and sensitive to Fusobacterium necrophorum are reindeer, cattle and small ruminants, pigs, and rabbits. A constant carrier of the causative agent of necrobacteriosis in the rumen and intestines of ruminants has been established, it is found in food particles during chewing, in feces, in objects of the external environment. The disease is especially often observed in animals kept in damp places with poor zoohygienic conditions. Infection of animals occurs when the pathogen enters the injured skin areas or when the mucous membranes are macerated. The work was carried out in the laboratory and production conditions of KazSRVI LLC and at the MTF of the Arkabay settlement of the Talgar district of the Almaty region, where stall keeping of animals is practiced. Material for laboratory research (sections from the horny tissue of the hoof on the border with the healthy one) were taken fresh and inoculated on a nutrient medium for anaerobes (Kitt-Tarozzi medium). Samples of the selected biological material were plated on Kitt-Tarozzi medium at the sampling site on the farm. The biological material taken from sick animals was examined within several hours after taking in accordance with the guidelines for laboratory diagnostics of necrobacteriosis (YEAR INDICATION METHOD). To get rid of the numerous accompanying microflora and obtain a pure culture of F. necrophorum, a bioassay was set up on laboratory animals - rabbits. On the 14-15th day after infection, the experimental rabbits died, which is evidence of the high pathogenicity of the isolated cultures. A pure culture of F. necrophorum from rabbit’s internal organs, not contaminated with extraneous microflora, was cultured. It was found that rabbits are the optimal biomodel for purification of the F. necrophorum culture. The results of cultivation of the causative agent of presented necrobacteriosis on solid and liquid nutrient media are. The biochemical properties of the isolated cultures have been studied. It was found that epizootic cultures of the causative agent of necrobacteriosis in cattle emitted hydrogen sulfide, formed ammonia, and had hemolytic properties. In experiments in vitro and in vivo, it was found that the isolated cultures of F. necrophorum showed hyaluronidase activity. Cultures of F. necrophorum had high catalase activity, i.e. split hydrogen peroxide with the release of gas bubbles. Four cultures of F. necrophorum, isolated from biological material from cattle, were identical in biological properties.