RU2501567C1 - Method for prevention of brucellosis in animals - Google Patents

Abstract

FIELD: medicine, pharmaceutics.

SUBSTANCE: invention refers to veterinary science, specifically prevention of infectious diseases. A method for prevention of brucellosis in animals is implemented as follows. Nitox 200 20 mg/kg is introduced intramuscularly into the affected animals. After 8 days, a vaccine of the strain B.abortus 19 in a dose of 1/10 of the standard subcutaneous dose is introduced subconjunctivally. The invention enables reducing the length of infection process arrest in the period of toxic-septic condition and post-vaccination reactions, thereby making it possible to conduct early post-vaccination studies, activating the health improvement in animals and reducing rejection of animals.

EFFECT: presented method for prevention of brucellosis may be used in the health improvement in brucellosis-unfavourable animal stocks.

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Description

The invention relates to veterinary medicine, namely to the prevention of infectious diseases.

Brucellosis is an infectious, chronically occurring disease of animals and humans. In epizootic and epidemic terms, the most dangerous infection caused in animals by the brucella of the species melitensis. With brucellosis, treatment of sick animals is not regulated.

There are two known methods for the recovery of herds of animals unfavorable for brucellosis - this is the complete replacement of the whole compromised livestock with healthy ones and the implementation of systematic mass diagnostic tests of animals for brucellosis in combination with the rational use of vaccines.

The first method is economically complicated.

The second is long and far from always possible. After the considerable time and money spent, the decision is often made to improve the dysfunctional herd in the first way, since the development of brucellosis infection cannot be stopped due to the specifics of the disease. Under certain conditions, brucellas circulating in the body, possessing the properties of long survival in it, transmission by the vertical route (from mother to offspring) and a wide range of variability of their pathogenic properties, can acquire a high degree of pathogenicity. In such cases, the identification of infected animals using various diagnostic methods and means and the creation of an immune background that impedes the conversion of brucellas circulating in the herd to highly pathogenic forms does not guarantee its reliable recovery - the course of the infection worsens or a relapse occurs during the recovery of the herd.

With animal brucellosis, there have been attempts to use various antibacterial drugs. Moreover, the emphasis was mainly on achieving a sanitizing effect, i.e. for the rehabilitation of sick animals [2, 4]. However, antibacterial drugs, stopping the infectious process during the period of the toxic-septic state, do not prevent the occurrence of relapses: the disease can become chronic.

The closest way to prevent brucellosis is the method proposed by Belobab V.I. [5]. The method includes the use of antibacterial drugs for animals in the acute course of brucellosis, followed by fractional administration of a vaccine from strain 82 or immunization with a non-living brucellosis vaccine.

The disadvantage of this method is the duration of the relief of the infectious process during the period of the toxic-septic state of the animal, due to the fact that antibiotics of non-prolonged action were used, and post-vaccination reactions persisted for a subcutaneous injection of the vaccine.

The technical result of the invention is to reduce the time for stopping the infectious process during the period of the toxic-septic state, as well as the manifestation of post-vaccination reactions in animals, which makes it possible to conduct post-vaccination studies earlier, which will speed up the improvement of the livestock and reduce culling of animals.

The claimed technical result of the method for the prevention of animal brucellosis includes intramuscular administration of an antibacterial drug followed by vaccine administration, Nitox 200 is used as an antibacterial drug at a dose of 20 mg / kg body weight once, and as a vaccine, a vaccine from B. abortus strain is administered conjunctively after 8 days 19 at a dose of 1/10 of the usual with subcutaneous administration.

When choosing an antibacterial agent from the perspective of its use, an important point is its wide spectrum of action, as well as prolonged action, ensuring a long stay in the body to provide the maximum antibacterial effect.

In relation to the effect on brucella, tetracycline antibiotics have positively proven themselves [2, 4]. Nita-Farm CJSC (Saratov) produces the Nitox 200 preparation, which is a prolonged-acting oxytetracycline dihydrate. This drug is widely used in veterinary practice in the treatment and prevention of many infectious diseases of animals.

An important criterion for choosing a vaccine is the adaptability of the method of application, as well as the ability to create the necessary level of immunity in animals and the possibility of conducting vaccine studies in the early stages to identify infected animals. The vaccine from B. abortus 19 strain meets these requirements with the conjunctival method of its administration in a dose reduced by 10 times compared with subcutaneous administration. Its effectiveness in various animal species has been proven in experimental and industrial conditions [1, 3].

The claimed method for the prevention of brucellosis is carried out as follows: Notox-200 is administered intramuscularly to sick animals with brucellosis at a dose of 20 mg / kg, then after 8 days a vaccine from B. abortus 19 strain is administered conjunctively at a dose of 1/10 of the usual with subcutaneous administration.

The proposed method will reduce the time of stopping the infectious process during the period of the toxic-septic state, as well as the manifestation of post-vaccination reactions in each animal, which provides the possibility of post-vaccination studies at an earlier date, which will speed up the improvement of the livestock and reduce culling of animals.

Example 1. Determination of the optimal dose of Nitox 200

Guinea pigs of four groups (5 animals each) are artificially infected with a virulent culture of B. melitensis 16M at a dose of 100 mk subcutaneously. After 20 days, the antibacterial drug Nitox 200 is administered intramuscularly in the following doses: group 1 - 200 mg per 1 kg of live weight; Group 2 - 20 mg / kg; Group 3 - 10 mg / kg. For animals of group 4, the drug is not administered - control. 10 days after the administration of Nitox 200, animals are euthanized. The biomaterial is examined bacteriologically. The test results are presented in table 1.

Table 1 The results of the use of various doses of Nitox 200 Group number The number of goals in the group Infectious strain, infection dose, route of administration Nitox 200: dose of administration 20 days after infection; mg / kg The result of bacteriological research (revealed brucelloniferous carriers) abs. number (n) % one 5 In melitensis 16M - 100 m.c., subcutaneous 200 - - 2 5 In melitensis 16M - 100 m.c., subcutaneous twenty one 20,0 3 5 In melitensis 16M - 100 m.c., subcutaneous 10 3 60.0 four 5 In melitensis 16M - 100 m.c., subcutaneous - 5 100.0

No brucella was isolated from animals of the 1st group of cultures. In the 2nd group of 5 animals, 1 culture with altered properties (RS-form) was isolated. In a 3 group of 5 animals, virulent Brucella cultures were isolated from 3 animals. In the control group, cultures of the infecting brucella strain were isolated from all animals.

Thus, with the introduction of different doses of Nitox 200 to animals infected with brucellosis, the optimal dose providing relief of the infectious process is recognized as a dose of 20 mg / kg body weight.

Example 2. The study of the effectiveness of the drug Nitox 200 in combination with vaccination

Guinea pigs of four groups (5 animals each) are artificially infected with a virulent culture of B. melitensis 16M brucella at a dose of 100 mk. After 20 days, Nitox 200 is administered to animals of the 1st and 2nd groups, intramuscularly at a dose of 20 mg / kg of live weight.

8 days after the introduction of Nitox, 200 animals of the 2nd group are injected with the vaccine from strain B. abortus 19, conjunctively at a dose of 100 million m.k. (1/10 of the standard dose for subcutaneous administration). Animals of the 3rd group, 28 days after infection with a virulent culture of brucella, are injected with a vaccine from strain B. abortus 19 conjunctively at a dose of 100 million m.k. (1/10 of the standard dose for subcutaneous administration). 4th group - control (animals artificially infected with a virulent culture of B. melitensis 16M at a dose of 100 mk). 1 month after vaccination of animals, euthanasia of all four groups of animals is carried out. The biomaterial is examined bacteriologically. The test results are presented in table 2.

In 1 group from 1 animal, the culture of the infecting strain in a typical form was isolated, and from 1 in an altered (RS) form. In group 2 cultures, brucella was not isolated. In group 3, the culture of the infecting strain was isolated from 4 animals. In the control group, virulent Brucella cultures of the infecting strain were isolated from all animals.

Thus, when Nitox 200 was administered to infected animals at a dose of 20 mg / kg body weight, followed by immunization after 8 days with a vaccine from strain B. abortus 19, conjunctively at a dose of 100 million m.k. (1/10 of the standard dose for subcutaneous administration), after a month not a single infected animal was detected.

table 2 The results of the use of Nitox-200 followed by vaccination of guinea pigs Group number The number of goals in the group Infection strain, infection dose, injection site Nitox 200, the dose of administration 20 days after infection; mg / kg Vaccination (vaccine, dose) The result of bacteriological examination (revealed brucello carriers) abs. % one 5 B. melitensis 16M 100 m.c., subcutaneous twenty - 2 40,0 2 5 B.melitensis 16M 100 m.c., subcutaneous twenty B.abortus19, conjunctival 100 mln.m. - - 3 5 B. melitensis 16M 100 m.c., subcutaneous - B.abortus19 conjunctival 100 million m.k. four 80.0 four 5 B. melitensis 16M 100 m.c., subcutaneous - - 5 100.0

The method allows for early vaccine studies, which will accelerate the improvement of the livestock and reduce culling of animals

The proposed method allows to reduce the time of stopping the infectious process during the toxic-septic state and the manifestation of post-vaccination reactions, providing the possibility of post-vaccination studies in the early stages, accelerating the improvement of the animal population and reducing culling of animals. The proposed method for the prevention of brucellosis can be used in the rehabilitation of herds of animals dysfunctional for brucellosis.

Literature

1. Zharova L.V. The effectiveness of the conjunctival method of immunizing sheep against brucellosis with a vaccine from strain 19: Dis .... Cand. vet. sciences. - Omsk, 2002 .-- 106 p.

2. Ivanov N.P. Animal brucellosis and measures to combat it. - Almaty, 2007.-518 p.

3. Kosilov I.A., Arakelyan P.K., Dimov S.K. et al. Brucellosis of farm animals / ed. I.A. Kosilova - Novosibirsk, 1999 .-- 344 p.

4. Krasikov A.P. Artificial regulation of parasitic-host relationships in animal brucellosis - Omsk, 2002. - 271 p.

5. Ten VB Methodological foundations of the manufacture and improvement of preventive anti-brucellosis drugs and diagnostic tools: Abstract. dis. ... doc. vet. sciences. - Almaty, 1996 .-- 45 p.

Claims (1)

A method for the prevention of animal brucellosis, including intramuscular administration of an antibacterial drug followed by a vaccine, characterized in that Nitox 200 is used as an antibacterial drug at a dose of 20 mg / kg once, and as a vaccine, a vaccine from B. abortus 19 strain is used conjunctively after 8 days at a dose of 1/10 of the usual with subcutaneous administration.