Relief of brucellosis in an acute focus of returning infection with the use of a vaccine from the strain B. abortus 82

Abstract

The purpose of the study was to study the features of the manifestation of the epizootic process during a returning infection in a fresh focus of brucellosis in cattle. The work was carried out on a dairy farm on a herd of cattle of a black-and-white breed, for a long time successful in brucellosis. The intensity of the epizootic process was assessed based on the results of serological studies of cattle of all sex and age groups. Immunological studies were carried out in accordance with regulatory documents on the diagnosis of brucellosis of animals. Standard diagnostic kits (S-) from commercial kits were used for serological studies in generally accepted reactions. Differentiation of positive and doubtful reactions was carried out using an experimental sample of an antigen made from brucella in R-form. A dynamic spread of brucellosis was noted during the six months with the 7% ill animals among all of the receptive cattle. Wellness measures were carried out with using the poorly agglutinogenic vaccine of strain Brucella abortus 82. The recovery period was 24 months. During of the trouble period 23% of infected animals were detected, including 19% of cows and 4% of young animals. The number of sick animals in a percent was estimated from the total numbers of the cattle in the farm. Based on the data obtained, it was established that under modern conditions, against the background of longterm well-being in a fresh focus of brucellosis, a dynamic spread of infection was noted with a wide coverage of susceptible livestock and a high intensity of the epizootic process.