RU2154495C2 - Inactivated emulsion-vaccine against salmonellosis in calves - Google Patents

Abstract

FIELD: veterinary science, microbiology. SUBSTANCE: invention relates to specific prophylaxis of sicknesses in animals. Inactivated vaccine against salmonellosis in calves has mixture of antigens of virulent immunogenic strains of serovaras Salmonella dublin, Salmonella typhimurium prepared in physiological solution, adjuvant and 0.4-0.5% (vol./vol.) of formalin as preserving agent. As antigens of serovara of Salmonella dublin vaccine has the strain Salmonella dublin N 1449. As antigen of serovara of Salmonella typhimurium vaccine has the strain Salmonella typhimurium N 159. As immunostimulating agent vaccine has suspension of cells Rhodococcus equi N 2 prepared in physiological solution. As adjuvant vaccine has oil-lanoline mixture. Vaccine provides the development of expressing long immunity in calf body. EFFECT: enhanced effectiveness of vaccine, decreased dose and dosing. 3 ex

Description

 The present invention relates to the field of veterinary microbiology, in particular to the production of an inactivated vaccine against calf salmonellosis.

Cattle salmonellosis is an infectious disease characterized by the phenomena of bacteremia, toxemia, abortion, or the birth of unviable young animals. Young animals aged 10-30 days are most susceptible to the disease. In the stock, the disease is manifested by abortion. In the acute course of young animals, the process begins with general inhibition and refusal of food. At the same time, body temperature rises to 41 ^o C and higher, develops adynamia and deposits, paresis of the forelimbs. With untimely treatment, death can occur 36-48 hours after the onset of clinical signs. With a prolonged course of the disease on the 2-3rd day, calves appear diarrhea. The feces become gray-yellow, with a lot of mucus and streaks of blood, have an unpleasant odor. The disease spreads according to the type of enzootia, grows gradually and for a long time is kept at a high level. At the same time, 80-90% of calves are often ill in a dysfunctional economy with a mortality rate of 20-80%. Damage consists of the cost of treatment, the death of young animals. The disease is recorded in all regions of the country. When using effective vaccines, the death of young cattle is reduced.

 Known vaccine concentrated formolquast against calf salmonellosis, produced by the Krasnodar Biofactory. The vaccine contains Salmonella Dubin and Tifimurium serovars. The vaccine is used to prevent cattle salmonellosis in farms that are unsuccessful for this disease. The vaccine is given twice to pregnant cows 50-60 days before calving, at doses of 10 and 15 ml with an interval of 8-10 days. Calves are immunized, starting from 1-2 days of age, twice, with an interval of 3-5 days at a dose of 1-1.5 ml for the first and 1.5-2 ml for the second vaccination. Upon reaching calves 1.5-2 months of age, they are revaccinated once in a dose of 2 ml. Calves obtained from vaccinated cows are vaccinated from 17-20 days of age, and calves from unvaccinated cows are vaccinated at 8-10 days of age twice in a dose of 1-2 ml with an interval of 8-10 days.

 A vaccine against salmonellosis of calves from an attenuated strain of Salmonella Dublin is also being used; live vaccine against salmonellosis of young animals / from strains of Salmonella typhimurium N 3 and Salmonella Dublin N 6 /. In salmonella-deficient farms, pregnant cows are immunized with a concentrated formolvac vaccine, which is administered as directed. Calves obtained from vaccinated cows are vaccinated with live vaccines at 17-20 days of age, once from unvaccinated cows at 10-15 days of age, at a dose of 1 billion live bw when administered subcutaneously or twice orally with an interval of 2 days at a dose of 100 billion mt, in the case of the vaccine against salmonellosis of young animals from the strains of Salmonella typhimurium N 3 and Salmonella Dublin N 6.

 The objective of our research is to obtain an inactivated, areactogenic vaccine against calf salmonellosis, which ensures the creation of intense, long-lasting immunity in the animal’s body, and reduces the frequency of administration.

 In the proposed vaccine, the following Salmonella strains were used as antigens: Salmonella Dublin N 1449 isolated from aborted fetuses in 1989; Salmonella typhimurium N 159, obtained from the museum of typical cultures of the bacteriology laboratory of the All-Russian Scientific Research Institute of Experimental Veterinary Medicine named after Ya.R. Kovalenko, Moscow.

 In addition, we used as an immunostimulant the Rhodococcus ekvi strain N 2 isolated from cattle from the farms of the Moscow Region in 1986.

 The proposed vaccine includes antigens of two Salmonella serovars: Dublin and typhimurium in physiological saline with 0.4-0.5% formalin, the adjuvant is an oil-lanolin mixture containing a suspension of Rhodococcus cells - an immunostimulant.

Strain Salmonella Dublin N 1449 has the following properties:
Cultural and morphological features
Gram-negative small sticks with rounded ends, 1-6 microns long, 0.4-0.6 microns wide, mobile. It grows well on ordinary nutrient media, forms a precipitate on the broth, uniform turbidity, film and parietal ring. On semi-liquid agar, it grows throughout the entire column of the medium.

Physiological and biochemical properties
Aerob, capable of growing in microaerobic conditions. The optimum pH of 7.2, temperature 37 ^o C.

 Does not split urea, does not form indole, releases hydrogen sulfide, ferments glucose, sorbitol, arabinose, maltose, utilizes citrate, sodium malonate, sodium citrate with glucose; has enzymes lysine decarboxylase and ornithine decarbase.

 Agglutinated by salmonella serums: 0 - 1,9,12; H - g, p, -.

Pathogenic for white mice: LD ₅₀ is 5 • 10 ⁴ cells with intraperitoneal infection.

Strain Salmonella typhimurium N 159 has the following properties:
Cultural and morphological features
Gram-negative, motile, small, slightly curved rods, forming on the MPA convex colonies 1-3 mm in diameter, transparent or whitish. They grow well on ordinary nutrient media, on the BCH they form a film and a parietal ring.

Physiological and biochemical properties
Aerob, capable of growing in microaerobic conditions. The optimum pH of 7.2, temperature 37 ^o C.

 Does not change milk, does not thin gelatin, does not secrete indole, does not decompose urea; emits hydrogen sulfide, ferments glucose, mannitol, sorbitol, arabinose, inositol, maltose with the formation of acid; lactose and sucrose does not ferment; has enzymes lysine decarboxylase and ornithine decarbase.

 Agglutinated by salmonella serum: 0 - 1,4,5,12; H is i; 1,2.

Pathogenic for white mice: LD ₅₀ is 5 • 10 ³ cells with intraperitoneal infection.

The strain of Rodococcus ekvi N 2 has the following properties:
Cultural and morphological features
Gram-positive, motionless rod-shaped and coccoid-shaped bacteria that form convex colonies up to 1 mm in diameter, grayish-yellow in color.

Slow growth is typical on ordinary nutrient media (up to 4-9 days), but when enriched with 10% serum at 37 ^o C, good growth is observed after 24 hours.

Physiological and biochemical properties
Aerob, optimum pH 7.2-7.4, temperature 30 ^o C.

In relation to carbohydrates, amino acids, polyhydric alcohols is not active, but ferments glucose. It does not form indole, hydrogen sulfide, does not decompose gelatin, and does not lyse red blood cells of animals. It has enzymes: catalase, urease. Non-pathogenic - when administered intraperitoneally to white mice weighing 18-20 g at a dose of 10 • 10 ⁹ microbial bodies does not cause their death within 14 days.

A method of preparing a vaccine is as follows:
Example 1. To prepare 1 liter of vaccine take a mixture of antigens prepared in saline with 0.4-0.5% formalin. The concentration of cells in 1 ml of suspension is 90 billion mt

Antigens: Salmonella dublin - 300
Salmonella typhimurium - 100
A suspension of Rodococcus equi cells in physiological saline, containing 100 ml in 200 ml of microbial cells.

 Light mineral oil and anhydrous lanolin in a ratio of 83-87: 17-13 - the rest.

 After mixing all the components, the formalin concentration will be 0.2-0.25%.

 A vaccine is used once in a dose of 2.0 ml for cows and 1.0 ml for calves with a preventive purpose in livestock farms that are unsuccessful for calf salmonellosis.

Example 2. The vaccine is prepared analogously to example 1, but take a mixture of antigens prepared in physiological saline with 0.4-0.5% formalin / 1 ml of bacterial suspension contains 90 billion microbial cells / in the following amount: / ml /
Antigens: Salmonella dublin - 285
Salmonella typhimurium - 95
A suspension of rhodococcal cells in physiological saline containing 1 ml of 200 billion microbial cells - 95 ml.

 Oil-lanolin adjuvant in a ratio of 83-87: 17-13 - the rest.

 Example 3. The vaccine is prepared analogously to example No. 1, but they take a mixture of antigens prepared in physiological saline containing 0.4-0.5% formalin / 90 ml of microbial cells are contained in 1 ml /.

Antigens: Salmonella dublin - 315
Salmonella tuphimurium - 105
A suspension of microbial cells of Rhodococcus / concentration in 1 ml of 200 billion mcl / - 105 ml.

 Oil-lanolin mixture in a ratio of 83-87: 17-13 - the rest.

 The components of the vaccine named in one example 1,2,3 are placed in a homogenizer and after 10-15 minutes of homogenization the vaccine is packaged in bottles.

 As can be seen from the examples, the proposed vaccine is areactogenic, provides the creation in the animal’s body of long-term and intense immunity against calf salmonellosis with a single administration of 1.0 ml to calves, 2.0 ml to cows 50-60 days before calving.

 We tested the vaccine on 105 calves and 53 cows with a positive result in 1995-1997.

 The vaccine will find application in livestock farms that are unsuccessful for calf salmonellosis.

Claims (1)

 Inactivated emulsion vaccine against calf salmonellosis, including a mixture of antigens of virulent, immunogenic strains from serovars Salmonella dublin, Salmonella typhimurium in physiological saline, adjuvant, preservative 0.4-0.5% (vol./about.) Formalin, characterized in that as serovar antigens, Selmonella dublin contains Salmonella dublin strain N 1449, as a Salmonella typhimurium serovar antigen contains Salmonella typhimurium strain N 159, as an immunostimulant contains a suspension of Rodococcus equi N 2 cells in the oil-lanolin mixture, while the components included in the vaccine are t in the following ratio per liter: antigens in physiological saline with the addition of 0.4 - 0.5% formalin and a concentration of microbial cells in 1 ml - 90 billion: antigen Salmonella dublin N 1449 285 - 315 ml, antigen Salmonella typhimurium N 159 95 - 105 ml, a suspension of Rodococcus equi N 2 cells in physiological saline containing 200 billion microbial cells in 1 ml 95 - 105 ml; adjuvant - maslanolin mixture in a ratio of 83 - 87: 17 - 13 the rest.