One of the main issues in the safety of animal and human health in our time is bioterrorism. One of the bacterial pathogens used as an agent is Bacillus anthracis. The causative agent causes anthrax disease and can be used for massive impressions, leading to significant economic losses for countries. Prevention of anthrax develops antisubmarine vaccines. Abroad use the licensed vaccine AVA (Anthrax Vaccine Adsorbed) from the strain V770-NP1-R (USA), the strain Langzhou A16R (China) and others.

In Ukraine, as a result of vaccination, anthrax occurs sporadically. According to the results of the research, it was found that the largest number of diseased animals in the year was observed in Volyn (1994), Luhansk (1994), Kherson (1999), Odessa (2000), and Kyiv (2001) regions.

The development of preventive study does not stop and scientists are looking for better indicators when using live vaccines. During the development of vaccine digs, various properties of strains are studied in laboratory animals, in particular in Guinea pigs. In determining the immune status of experimental animals with anthrax, it is necessary to take into account not only the humeral and cellular indices of the factors of protection.

The purpose of the research is to study the optimum immunization dose of vaccine against anthrax, produced from the strain of Bacillus anthracis UA–07 in laboratory animals.

The experimental series of the vaccine against anthrax of animals from the strain Bacillus anthracis UA–07 "Antravak" was used in this work. The control strain (strain punch) used strain Bacillus anthracis M-71 from the collection of the National Center for strains of microorganisms.

Determination of pathogenic activity of the test strain Bacillus anthracis M–71 was carried out on clams weighing 350-400 g. Concentration of the dispute was determined in the camera Guryev. The breeding of spore suspension strain was carried out in isotonic sodium chloride solution and subcutaneously from the inner surface of the right hip was infected with mollusks. Animal monitoring was carried out for 10 days. Fixed the death of experimental animals. To determine the optimum immunization dose of the live spore vaccine created, a series of vaccine No. 1 containing 13.03 million spores / cm³ was used.

It was found that all the mullets were killed in the groups that were administered 10000 and 12000 spores. Consequently, 1 MLD of the control strain of Bacillus anthracis M–71 was 1,106 spores, since the mortality of the Guinea pigs was 100% (2–3 days after the injection).

The results of the studies on the study of the optimum immunization dose of Bacillus anthracis UA–07 strain indicate that anthrax vaccine Anthravac manufactured from the strain Bacillus anthracis UA–07 did not cause an increase in body temperature above 1 ^oC from physiological norm, inhibition, anaphylactic shock, local reactions.

Introduction to experimental animals of Bacillus anthracis M–71 culture resulted in an increase (38,87 ± 0,54 ^oC) of body temperature and death in control animals on the second day. Vaccination of animals in different amounts of spores (7,82–11,73 million spores) resulted in a slight increase (within 37,70 ± 0,25 – 38,52 ± 0,21 ^oC) of body temperature.

The obtained data on the study of the optimal immunization dose on the Guinea pigs, indicate that during the period of observation after administration of the Bacillus anthracis M–71 culture, the control animals of the control animals died from the second to the fourth day (100%). Experimental groups of animals that received spores of Bacillus anthracis UA–07 strain in the amount of 7,82–23,45 million spores remained alive (100%).

The highest immune protection was in the Guinea pigs  of 3–8 groups, which received 7,82–3,45 million spores of Bacillus anthracis UA–07.

It should be noted that the dose of 5,21 million spores caused protection in 60% of vaccinated animals, while the highest number of spores – 6,52 million was introduced in the body of Guinea pigs, caused 70% protection. In the third group of animals, the level of protection against the pathogenic strain of Bacillus anthracis M–71 was 80 %. An increase in the number of controversies entered to 23,45 million – has led to the protection of 100% of clams.

Thus, the strain Bacillus anthracis UA–07 in the dose from 7,82 to 23,45 million live spores provides immunity against the introduction of 1,0x10⁶ live spores of the Bacillus anthracis M–71 strain. Anthravac vaccine studies have shown a high level of protection in vaccinated animals against the control strain Bacillus anthracis M–71 at a dose of 7,82–23,45 million spores.

Anthravac vaccine, made from the Bacillus anthracis UA–07 strain, provided protection for Guinea pigs  at doses of 9,12, 10,42, 12,38, 13,03 and 23,45 million spores at a level of 100%. The protection of Guinea pigs at the level of 80% provided vaccine doses of 7,82 million spores.