Broad-spectrum bacteriophage composition for preventing and controlling swine atrophic rhinitis and application of broad-spectrum bacteriophage composition

Abstract

The invention relates to the technical field of biological medicines, discloses a broad-spectrum bacteriophage composition for preventing and controlling swine atrophic rhinitis and application of the broad-spectrum bacteriophage composition, and particularly relates to a pasteurella bacteriophage SD-PM1 and a bordetella bronchiseptica bacteriophage SD-Bb1, and the preservation numbers of the pasteurella bacteriophage SD-PM1 and the bordetella bronchiseptica bacteriophage SD-Bb1 are CCTCC NO: M20232599 and CCTCC NO: M20232589 respectively. The bacteriophage and the composition thereof have a strong broad-spectrum lysis effect on porcine pasteurella and porcine bordetella bronchiseptica, and the bacteriophage can be independently compounded with cocktail or compounded with cocktail, and can be used for preparing medicines for preventing and treating porcine respiratory diseases caused by independent infection or mixed infection of pasteurella and bordetella bronchiseptica. The traditional Chinese medicine composition especially has a remarkable effect on atrophic rhinitis of pigs. In addition, the bacteriophage provided by the invention is a strong bacteriophage, has a wide lysis spectrum, has good biological characteristics of acid resistance and heat resistance, and can also be applied to various actual scenes.

Description

Technical Field

[0001] The present invention relates to the field of biomedicine technology, and in particular to a broad-spectrum phage composition for preventing and controlling porcine atrophic rhinitis and applications thereof. Background Art

[0002] Pasteurella multocida (PM), a Gram-negative facultative anaerobic bacterium belonging to the family Pasteurellaceae and the genus Pasteurella, is a zoonotic pathogen that primarily causes a variety of diseases, primarily respiratory infections. Bordetella bronchiseptica (Bb) often forms a synergistic infection with PM, enhancing its colonization ability. Bb can also interact with other respiratory pathogens (including Streptococcus suis, Mycoplasma, Streptococcus parasuis, porcine reproductive and respiratory syndrome virus, and swine influenza virus) to cause disease.

[0003] In pigs, capsular types A and D of Pasteurella multocida are prevalent, primarily causing Pasteurellosis pneumonia and atrophic rhinitis (AR). Bordetella bronchiseptica infection alone can lead to non-progressive atrophic rhinitis in pigs. Pigs with atrophic rhinitis primarily exhibit facial distortion, nasal turbinate atrophy, and growth retardation. Furthermore, pigs with weakened immune systems are susceptible to other respiratory diseases, leading to increased mortality and significant economic losses for the pig farming industry. Therefore, developing a combination formulation capable of simultaneously controlling Bordetella bronchiseptica and Pasteurella multocida would significantly address current clinical farming challenges.

[0004] In recent years, drug resistance in Bordetella bronchiseptica and Pasteurella multocida isolated from production lines has continued to increase. The declining sensitivity of antibiotics has become a major obstacle to controlling these diseases. Bacteriophages are viruses that specifically engulf bacteria and are widely found in soil, sewage, and feces, representing a biodiverse population. Phages are classified as lytic phages and temperate phages based on their mode of parasitism. Phages that lyse host cells and release progeny phage particles are called lytic phages, virulent phages, or virulent phages, and are therefore considered to have potential for clinical application. Phages offer significant advantages as therapeutic and control tools: first, they are widely available and biologically active, allowing them to co-evolve with bacteria; second, they are highly specific, lysing only targeted pathogens rather than acting on all bacteria, thus minimizing microbial imbalance in animals. They have therapeutic effects against some clinically isolated multidrug-resistant bacteria and can synergize with antibiotics to induce bacterial "resensitization." Research has shown that bacteriophages are significantly more effective than antibiotics and other organic chemical additives, and have promising applications, particularly in the control of clinical medical infections, the prevention and control of veterinary clinical pathogens, and environmental contamination by food-related pathogens. Therefore, developing bacteriophages with a broad host spectrum is of great significance. Summary of the Invention

[0005] In view of this, the present invention proposes a broad-spectrum phage composition for preventing and controlling porcine atrophic rhinitis and its application, aiming to provide a broad-spectrum phage composition that can effectively prevent and control porcine atrophic rhinitis caused by Pasteurella multocida and Bordetella bronchiseptica, and through a specific application method, achieve efficient, safe and environmentally friendly prevention and control of porcine atrophic rhinitis.

[0006] The present invention provides a phage composition, comprising a Pasteurella phage SD-PM1 and a Bordetella bronchiseptica phage SD-Bb1;

[0007] The deposit number of the Pasteurella phage SD-PM1 is CCTCC NO: M20232589

[0008] The deposit number of the Bordetella bronchiseptica phage SD-Bb1 is CCTCC NO: M20232599.

[0009] The present invention also provides an application of the above-mentioned phage composition, wherein the application comprises at least one of the following:

[0010] A1) Use of the above-mentioned phage composition in the preparation of a product for treating porcine atrophic rhinitis;

[0011] A2) Use of the above-mentioned bacteriophage composition in sterilization;

[0012] A3) Use of the above-mentioned bacteriophage composition in the preparation of a sterilization product.

[0013] Preferably, the sterilization is sterilization of the environment, instruments and / or the surface of the skin.

[0014] Preferably, the bacterium species to be sterilized is Pasteurella or Bordetella bronchiseptica.

[0015] The present invention also provides a medicine for treating porcine atrophic rhinitis, which comprises the above-mentioned phage composition.

[0016] Preferably, the phage composition is in the form of a powder, a lyophilized preparation, a granule or a solution.

[0017] The present invention also provides a sterilization product, which comprises the above-mentioned bacteriophage composition.

[0018] The present invention also provides a feed additive, which includes the above-mentioned bacteriophage composition.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The bacteriophage involved in the present invention is a lytic phage, does not have a lysogenic module, and does not contain potential horizontal transfer elements such as drug resistance genes and virulence genes. Therefore, it has high safety in practical applications.

[0021] 2. The bacteriophage involved in the present invention is specific for two major respiratory pathogens and can effectively treat single pathogen infections and mixed infections, thereby broadening the scope of its clinical application.

[0022] 3. The bacteriophage involved in the present invention is a broad-spectrum bacteriophage, which exhibits extremely strong lysis ability against porcine toxigenic Pasteurella multocida, with a lysis rate of up to 100%. It also has a lysis rate of 100% against Bordetella bronchiseptica.

[0023] 4. The two phages involved in the present invention exhibit excellent biological properties. They can still maintain activity after 120 minutes of treatment in the pH range of 3 to 12, showing a wide pH tolerance range. In particular, SD-Bb1 has excellent heat resistance and can still survive after 60 minutes of treatment at 80°C in the absence of heat-resistant protective agents. This makes it suitable for a variety of production and processing processes and adaptable to extreme breeding environments.

[0024] 5. The bacteriophage involved in the present invention is derived from the natural environment, is easy to obtain and can be directly applied to actual production and transformation, which helps to reduce the cost of controlling specific bacterial pathogens; at the same time, a variety of application scenarios can be selected according to different needs, including pig food slaughtering and processing, breeding environment, feed and other aspects, to achieve multi-dimensional and all-round prevention and control of important respiratory pathogens - Bordetella bronchiseptica and Pasteurella multocida. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0026] Figure 1 This is the plaque morphology of phage SD-PM1 on a double-layer agar plate;

[0027] Figure 2 The plaque morphology of phage SD-Bb1 on a double-layer agar plate;

[0028] Figure 3 The morphology of bacteriophage SD-PM1 under electron microscope;

[0029] Figure 4 The morphology of bacteriophage SD-Bb1 under electron microscope;

[0030] Figure 5 The pH stability test results of bacteriophage SD-PM1;

[0031] Figure 6 The pH stability test results of bacteriophage SD-Bb1;

[0032] Figure 7 This is the thermal stability test result of bacteriophage SD-PM1;

[0033] Figure 8 The results of thermal stability test of bacteriophage SD-Bb1 are shown;

[0034] Figure 9 The optimal MOI test results of phage SD-PM1 and SD-Bb1;

[0035] Figure 10 The results of in vitro antibacterial test of bacteriophage SD-PM1 are shown;

[0036] Figure 11 The results of in vitro antibacterial test of bacteriophage SD-Bb1 are shown;

[0037] Figure 12The figure shows the results of the experimental treatment of porcine atrophic rhinitis with the SD-PM1 and SD-Bb1 phage combinations;

[0038] Figure 13 This is the statistical comparison of pig mortality before and after aerosol treatment;

[0039] Figure 14 The results show the changes in the coughing ratio of pigs before and after aerosol treatment. DETAILED DESCRIPTION

[0040] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, unless there is a conflict, the embodiments of the present disclosure and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0041] Example 1 Isolation and Purification of Bordetella bronchiseptica Phage and Pasteurella phage

[0042] (1) Host strain recovery process: Strains PM23001 and Bb23001 frozen at -80°C were streaked onto TSA plates (containing 5% newborn calf serum) for recovery and then cultured in a 37°C incubator for 18-24 hours. A single colony was selected and inoculated into 5 mL of TSB broth (containing 5% newborn calf serum) and incubated in a 37°C incubator at 180 rpm for 16 hours to harvest a single colony suspension.

[0043] (2) Pretreatment of environmental wastewater samples: Samples collected from pig farms, sewage, respiratory secretion swabs, etc., are mixed and soaked in SM solution. The mixture is allowed to stand for 4-6 hours and then centrifuged at 6000 rpm for 10 minutes. Repeat the centrifugation until the liquid is clear. The liquid is then filtered through a 0.22 μm filter to harvest the phage stock solution.

[0044] (3) Phage proliferation method: The phage stock solution was mixed with the host bacterial suspension at a volume ratio of 10:1, and co-enriched by adding TSB broth containing 5% newborn calf serum. The culture was incubated at 37°C in a constant temperature shaker at 180 rpm for 8-12 hours. The culture was then centrifuged at 8000 rpm for 20 minutes and filtered through a 0.22 μm filter to harvest the phage proliferation solution.

[0045] (4) Phage isolation technology: Phage isolation is performed using the double-layer plate method. The host bacteria and phage proliferation solution are mixed at a volume ratio of 1:1 and added to a 10 ml centrifuge tube. The mixture is incubated at 37°C for 5-10 minutes. Subsequently, 5 ml of the upper semi-solid culture medium is added and quickly poured onto the lower TSA solid plate (containing 5% newborn calf serum). The culture dish is gently shaken to mix. After solidification, it is inverted and cultured in a 37°C constant temperature incubator overnight. If phages are present, transparent, regular circular plaques will appear on the surface of the culture dish. Otherwise, the surface of the culture medium will show a uniform bacterial lawn.

[0046] (5) Phage purification process: Purify phage using the single plaque dilution method. Use a sterile 10 μl pipette tip to pick up a single transparent phage plaque and add it to a 1 ml centrifuge tube containing 900 μl PBS. After shaking and mixing, dilute 10-fold to 10 -5 , 10 -6 , 10 -7 . Take the host bacterial solution and different gradient dilution solutions in a volume ratio of 1:1 and mix them into a 10ml EP tube. Add 5ml of the upper semi-solid culture medium (containing 5% newborn calf serum) and quickly pour it into a TSA solid plate. After solidification, invert it and culture it in a 37℃ constant temperature incubator for 12-16 hours. Purify the phage by repeating 3-5 single-plaque dilutions until transparent, uniform, and morphologically consistent phage plaques appear. The phage morphology of SD-PM1 and SD-Bb1 on double-layer agar plates is shown in Figure 2. Figure 1 、 Figure 2 .

[0047] (6) Phage enrichment strategy: The liquid proliferation method was used for enrichment. The host bacterial liquid was inoculated into a 100 ml TSB broth (containing 5% newborn calf serum) triangular conical flask at a ratio of 1:100. A 10 μl sterile pipette tip was then added to pick up the purified single-plaque phage. The phage was cultured in a 37°C constant temperature shaker until clear. The phage enrichment liquid SD-PM1 and SD-Bb1 were harvested after filtering through a 0.22 μm filter.

[0048] (7) Phage freezing method: Take 750 μl of each of the enriched liquid SD-PM1 and SD-Bb1 harvested after filtration, mix them with 750 μl of each of 50% sterile glycerol, add them to 2 mL cryovials, and freeze at -80°C.

[0049] Example 2 SD-PM1, SD-Bb1 phage titer determination

[0050] The titer of phage SD-PM1 and SD-Bb1 was determined by double-layer plate method. First, the phage enrichment solution SD-PM1 and SD-Bb1 were serially diluted 10-fold with SM solution, with a dilution gradient of 10 -1 -10 -7. Subsequently, 2 to 3 appropriate dilutions were selected, and 100 μL of dilution solution and 100 μL of host bacterial suspension were drawn up with a sterile pipette tip, mixed in a 10 ml EP tube, and incubated at 37°C for 5 minutes. Next, 5 mL of the upper semi-solid culture medium was added and mixed thoroughly, and then poured onto the lower TSA solid culture medium. The experiment was repeated 3 times for each dilution. After the plate solidified, it was inverted and cultured at a constant temperature of 37°C for 8-12 hours. Observe and record the morphology of single, uniform plaques, and count the number of effective plaques (30-300). According to the formula: phage titer = average number of effective plaques × dilution factor × 100 (PFU / mL), the titer of phage SD-PM1 was calculated to be 1.08×10 9 PFU / mL, and the titer of SD-Bb1 was 3.45×10 9 PFU / mL.

[0051] Example 3 Electron microscopic observation of SD-PM1 and SD-Bb1 phages

[0052] Take 20 μl of fresh phage enrichment solution SD-PM1 and SD-Bb1, drop them on copper mesh respectively, cover with filter paper and dry with incandescent lamp, then use phosphotungstic acid (PTA, 2% w / v) to stain the copper mesh, and observe the phage morphology using transmission electron microscope after drying. Figure 3 、 Figure 4 .

[0053] PMPH001 Figure 3 The results showed that the phage was Pasteurella suispage SD-PM1 (Pasteurelia suispage SD-PMl), which was deposited in the China Center for Type Culture Collection on December 18, 2023, with the deposit number CCTCCNO: M20232589.

[0054] SD-Bb1 Figure 4 The results showed that the phage was Brodetella bronchiseptica page SD-Bb1, which was deposited in the China Center for Type Culture Collection on December 19, 2023, with the deposit number CCTCC NO: M20232599.

[0055] Example 4 pH stability of SD-PM1 and SD-Bb1 phages

[0056] Take 100 μl each of fresh phage enrichment solution SD-PM1 and SD-Bb1, and adjust the phage titer to 1.5×10 8 PFU / mL, 1.0×10 9PFU / mL. Set the pH gradient of SM solution to 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12, with a total of 11 groups. Add 100μl of phage enrichment solution to an EP tube containing 900μl of SM solution, and set up 3 replicate tubes for each pH group. Place each tube in a constant temperature water bath preheated to 37°C, and use the double-layer agar plate method to determine the current phage titer when the action time reaches 10min, 30min, 60min, and 120min respectively. For detailed experimental results, see Figure 5 、 Figure 6 .

[0057] The experimental results showed that both SD-PM1 and SD-Bb1 phages could survive for extended periods within a pH range of 3-12. After one hour at pH 3, the titers of both phages did not decrease by more than two orders of magnitude. The titer of SD-PM1 varied minimally within the pH range of 4-11, while the titer of SD-Bb1 varied by an average of one order of magnitude within the pH range of 3-12, demonstrating that both SD-PM1 and SD-Bb1 phages possess strong tolerance to acid and alkaline environments.

[0058] Example 5 Thermal stability of SD-PM1 and SD-Bb1 phages

[0059] Take 100 μl each of fresh phage enrichment solution SD-PM1 and SD-Bb1, and adjust the phage titer to 1.5×10 8 PFU / mL. Add 100μl of phage enrichment solution to an EP tube containing 900μl of SM solution. Place each EP tube in a water bath at 40℃, 50℃, 60℃, 70℃, and 80℃, with 3 replicate tubes for each temperature group. After the exposure time reaches 30min, 60min, 90min, and 120min, the current phage titer is determined using the double-layer agar plate method. The results are shown in Figure 7 、 Figure 8 .

[0060] The results are as follows Figure 7 and Figure 8 As shown, PM1 has high activity in the range of 4-50℃, and completely loses its activity after being exposed to 60℃ for 30 minutes; BbPH001 has good survival ability in the range of 4-70℃, and completely loses its activity after being exposed to 80℃ for 75 minutes, showing strong thermal stability.

[0061] Example 6 Optimal multiplicity of infection of SD-PM1 and SD-Bb1 phages

[0062] Pasteurella multocida and Bordetella bronchiseptica were used as liquid propagation host bacteria, and their corresponding phages PMPH001 and BbPH001 were inoculated at MOIs (multiplicity of infection) of 10, 1, 0.1, 0.01, 0.001, and 0.0001, respectively. Three replicates were performed for each MOI. The EP tubes were placed in a 37°C incubator and shaken at 180 rpm for 6-8 hours. After centrifugation at 8000 rpm for 15 minutes, the phage titer in the supernatant was determined using a double-layer plate method to determine the optimal phage MOI.

[0063] like Figure 9 As shown, the titer of phage PMPH001 exceeded 10 at MOI range of 1 to 0.0001. 9 PFU / mL, with the decrease of MOI ratio, the titer showed a slow upward trend, and the optimal MOI was 0.0001; while the titer of bacteriophage BbPH001 exceeded 10 at MOI of 0.1. 10 PFU / mL, and the optimal MOI was 0.1.

[0064] Example 7 Lysis spectrum experiment of SD-PM1 and SD-Bb1 phage

[0065] Resuscitation experiments were conducted on Pasteurella multocida and Bordetella bronchiseptica strains, all of which were stored in a laboratory cryopreservation bank. The resuscitated strains were incubated at 37°C in a shaker at 180 rpm for 6 hours until they reached the logarithmic growth phase. Subsequently, the lysis profiles of bacteriophages PMPH001 and BbPH001 were determined using a double-layer plate method. Table 1 shows the lysis profiles of phages SD-PM1 and SD-Bb1.

[0066] Table 1

[0067]

[0068]

[0069] PMPH001 is a broad-spectrum phage with broad lytic activity, effectively lysing porcine Pasteurella types A and D isolated from clinical sites, as well as those for which capsular typing could not be performed. SD-Bb1 phage also exhibits a broad lytic spectrum.

[0070] Example 8 In vitro antibacterial experiment of SD-PM1 and SD-Bb1 phages

[0071] Use freshly prepared TSB growth medium of host bacteria PM23001 and Bb23001, and adjust the bacterial concentration to 1×10 8CFU / ml, respectively, with different MOI of phage enrichment liquid SD-PM1 (MOI = 0.01, 0.1, 1), BbPH2300 (MOI = 0.1, 1) for in vitro host culture experiments. By measuring the OD600 value of bacteria over a period of time, each group of experiments was repeated three times. The experimental results are detailed in Figure 10 、 11 .

[0072] like Figure 10 As shown in the results, under in vitro culture conditions, the phage PMPH001 exhibited a significant inhibitory effect on the host bacteria in the treatment group with MOI = 0.01 to 1, compared with the bacterial control group, and the effect lasted up to 8 hours; while the phage BbPH001 had an inhibitory effect of up to 13 hours under MOI = 0.1; under MOI = 0.01, the long-term inhibitory effect of the phage on the host bacteria was more significant.

[0073] Example 9 Experiment 1 on the treatment of porcine atrophic rhinitis with SD-PM1 and SD-Bb1 phage combinations

[0074] In the slaughterhouse of a large group pig farm, a high detection rate of Bordetella was found when nasal swabs were tested on pigs in the fattening stage, indicating that there was a significant pressure of respiratory diseases on the farm. In order to evaluate the damage to the nasal concha, the slaughtered pigs were subjected to nasal concha autopsy and scoring, and a total of 50 samples were randomly inspected. The results showed that all the sampled samples showed damage to the nasal concha, and the degree of damage was severe (score ≥ 3 points), of which the proportion of severe damage reached 100%. Specifically, the number of samples with a score of 0-2 points was 0, there was 1 sample with a score of 3 points (accounting for 2%), there were 48 samples with a score of 4 points (accounting for 96%), and there was 1 sample with a score of 5 points (accounting for 2%). Related results are as follows Figure 12 shown.

[0075] In view of the situation of the group's pig farm slaughterhouse, two sow production lines were selected for research, each line has 2,000 basic sows, and the regional stocking scale is about 40,000. The main disease problems faced by the sow line include the instability of blue ear disease and the severity of respiratory diseases such as atrophy rhinitis and secondary infections such as Haemophilus parasuis, resulting in a stocking loss rate of up to 12-15%. This embodiment applies the phage composition of the present invention (the ratio of the two phages is 1:1), and nasal spray treatment is performed on sows 3 days before delivery, during the nursing period of piglets, and within 3 days after weaning of piglets. The phage dosage used for nasal spray is 1.0 ml / pig (containing a phage concentration of not less than 10 8 PFU / ml) and the cough rate and tear stains of sows were recorded. The relevant results are detailed in Table 2.

[0076] Table 2

[0077]

[0078]

[0079] It can be seen that the proportion of piglets in the experimental group who developed respiratory symptoms after taking phage nasal spray was significantly lower than that in the control group.

[0080] Example 10 Experiment 2 on the treatment of porcine atrophic rhinitis with the SD-PM1 and SD-Bb1 phage combinations

[0081] At a large-scale pig farm, the bacteriophage combination of the present invention was tested on selected breeding pigs. The experimental groups were divided into the following groups: the aerosol group received aerosolized bacteriophage treatment and enoxacin for two days, followed by aerosolized amoxicillin for two days, for a total of four days of aerosol treatment; the control group maintained conventional feed mixing and health care measures.

[0082] The test results are as follows:

[0083] 1. Changes in pig mortality before and after aerosol treatment

[0084] according to Figure 13 The data shown do not show a significant difference in daily mortality between the nebulizer group and the control group during the observation period. However, the overall trend suggests a lower mortality rate in the nebulizer group. Even after cessation of nebulizer therapy, the mortality rate in the nebulizer group remained lower than that in the control group.

[0085] 2. Changes in the proportion of pigs coughing before and after atomization treatment

[0086] according to Figure 14 The data showed that the cough rate in the nebulized group was significantly lower than that in the control group. Within two days of combined nebulized treatment with bacteriophage and enrofloxacin, the cough rate dropped rapidly from 4.42% to 2.14%. After two days of continued amoxicillin nebulized treatment, the cough rate in the nebulized group remained stable until the 19th, when the cough rate in the nebulized group dropped to 2.86%, while the control group's feed mixing and health care measures only reduced the cough rate to 1.14%. The nebulized group had basically no coughing from the 21st to the 22nd, while the coughing in the control group continued until the 27th, significantly shortening the coughing cycle. The results of the study show that the combined nebulized treatment of bacteriophages and antibiotics is significantly more effective than traditional feed mixing and health care measures in improving respiratory symptoms in pigs.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. A bacteriophage composition, characterized in that: These include the Pasteurella phage SD-PM1 and the Bordetella bronchiseptica phage SD-Bb1; The deposit number of the Pasteurella phage SD-PM1 is CCTCC NO: M20232589 The deposit number of the Bordetella bronchiseptica phage SD-Bb1 is CCTCC NO: M20232599.

2. A use of the phage composition according to claim 1, characterized in that: The application includes at least one of the following: A1) Use of the phage composition according to claim 1 in the preparation of a product for treating porcine atrophic rhinitis; A2) Use of the bacteriophage composition according to claim 1 in sterilization; A3) Use of the bacteriophage composition according to claim 1 in the preparation of a bactericidal product.

3. The use according to claim 2, characterized in that The sterilization is the sterilization of the environment, instruments and / or the surface of the skin.

4. The use according to claim 2 or 3, characterized in that The bacterium species to be sterilized is Pasteurella or Bordetella bronchiseptica.

5. A drug for treating porcine atrophic rhinitis, characterized in that: The drug comprises the phage composition according to claim 1.

6. The medicament for porcine atrophic rhinitis according to claim 5, characterized in that: The phage composition is in the form of powder, lyophilized agent, granule or solution.

7. A sterilization product, characterized in that: The bactericidal product comprises the bacteriophage composition according to claim 1.

8. A feed additive, characterized in that The feed additive comprises the phage composition according to claim 1.

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