Rudoi O. Actinobacillosis (lignieriosis) in cattle (epizootiology, diagnostics and prevention)

The decision of a scientific problem is presented in the study of the epizootic situation concerning cattle actinobacillosis in Ukraine, development and improvement of diagnostic methods and specific prevention of the disease. For the first time there has been carried out the analysis of epizootic situation concerning actinobacillosis in cattle in Ukraine for the period 2001-2013. Based on the results of own researches there were registered 81 sites of concern in 13 regions of Ukraine and Crimea. Level of impression in cattle ranged from 3 to 90 % of the available stock, especially in the group - fattening calves up to 55 %. Intermediate impression was 30 %, and separately for regions - from 12 to 52.5 %. Stationary and relatively high tension of the epizootic situation concerning actinobacillosis was noted in the central and eastern regions, especially in Vinnitsa and Donetsk regions. It has been established that actinobacillosis in cattle is characterized by half acute course of lymph vessels and nodes mainly head and neck, rarely ulcerative lesions of the tongue. The general state of the animals depends on the location of the pathological process. In chronic cases there are proliferative processes in the lymph nodes and internal organs with forming abscesses in the lungs and stomach, loss of productivity, reducing the increase in body weight to 310 g per day and premature culling of animals. During bacteriological studies of pathological material suspected on actinobacillosis, pure culture of the pathogen A. lignieresii was isolated in 32.5%, often it was isolated in association with the cultures of C. perfringens (11.5 %) and St. aureus (9.2%), which complicated the disease and were pathogenic for laboratory animals. Separately there were isolated from parenchymal organs isolates of E. сoli - 15.8%, P. multocida - 6.9%. There were determined features of indication of actinobacillosis pathogen from pathological material, 7 isolates A. lignieresii have been identified. Collection of 17 epizootic strains isolated from different regions of Ukraine has been updated. On the basis of study the biological properties of the deposited strains and field isolates there have been improved methods for identification on generic and species level. It has been tested a new method of production of bacterial cell antigen A. lignieresii and received positive actinobacillosis serum (11.72 ± 0.22 log2) which have distinct species specificity for all isolates of actynobacillus in AT plate glass. According to the researches it has been developed comprehensive system for diagnostics of actinobacillosis (lignieriosis) in cattle on the base of epizootic, clinical, pathological-anatomical, bacteriological and serological methods, and - histological method for differential diagnosis of actinomycosis. For the first time on the base of study etiological structure of associated and mixed infections in the farms of Ukraine it has been developed an associated vaccine against actinobacillosis and colibacteriosis in cattle 'Actinokolisan'. The introduction of the vaccine 'Actinokolisan' in the farms ensured protection of calves from the born (on the 5th day antibody titers were to A. lignieresii - 6.3 ± 1.2 log2 and E. coli - 6.6 ± 0.4 log2) till 4 month age (5.5 ± 0,5 log2 and 6.2 ± 0.2 log2 respectively), and the effectiveness of vaccination of calf cows and calves from the age of 14 days against actinobacillosis and colibacillosis in calves was 100 and 80%, respectively.