Integrative and Conjugative Elements and Prophage DNA as Carriers of Resistance Genes in Erysipelothrix rhusiopathiae Strains from Domestic Geese in Poland.

Goose erysipelas is a serious problem in waterfowl breeding in Poland. However, knowledge of the characteristics of Erysipelothrix rhusiopathiae strains causing this disease is limited. In this study, the antimicrobial susceptibility and serotypes of four E. rhusiopathiae strains from domestic geese were determined, and their whole-genome sequences (WGSs) were analyzed to detect resistance genes, integrative and conjugative elements (ICEs), and prophage DNA. Sequence type and the presence of resistance genes and transposons were compared with 363 publicly available E. rhusiopathiae strains, as well as 13 strains of other Erysipelothrix species. Four strains tested represented serotypes 2 and 5 and the MLST groups ST 4, 32, 242, and 243. Their assembled circular genomes ranged from 1.8 to 1.9 kb with a GC content of 36-37%; a small plasmid was detected in strain 1023. Strains 1023 and 267 were multidrug-resistant. The resistance genes detected in the genome of strain 1023 were erm47, tetM, and lsaE-lnuB-ant(6)-Ia-spw cluster, while strain 267 contained the tetM and ermB genes. Mutations in the gyrA gene were detected in both strains. The tetM gene was embedded in a Tn916-like transposon, which in strain 1023, together with the other resistance genes, was located on a large integrative and conjugative-like element of 130 kb designated as ICEEr1023. A minor integrative element of 74 kb was identified in strain 1012 (ICEEr1012). This work contributes to knowledge about the characteristics of E. rhusiopathiae bacteria and, for the first time, reveals the occurrence of erm47 and ermB resistance genes in strains of this species. Phage infection appears to be responsible for the introduction of the ermB gene into the genome of strain 267, while ICEs most likely play a key role in the spread of the other resistance genes identified in E. rhusiopathiae.

Phenotypic and genotypic antimicrobial resistance profiles of fecal lactobacilli from domesticated pigeons in Poland.

Lactobacillus species play an important role in the host and although they are non-pathogenic, they could act as reservoirs for antibiotic resistance genes, with the potential risk of transfer to other bacteria inhabiting the gastrointestinal tract. The aim of this study was to identify Lactobacillus species derived from feces of domesticated pigeons and to characterize their phenotypic and genotypic antimicrobial resistance (AMR) profiles. A total of 57 Lactobacillus isolates were classified into six species using the MALDI-TOF technique and 16S rDNA restriction analysis. Strains of L. ingluviei (31%), L. salivarius (28%) and L. agilis (23%) were the dominant species isolated. Determination of antimicrobial susceptibility by the microdilution broth method showed widespread resistance to kanamycin (89%), tetracycline (84%), streptomycin (63%), and enrofloxacin (37%). Less than 30% of the isolates were resistant to erythromycin, lincosamides, gentamycin, chloramphenicol and vancomycin. Over half (51%) of the lactobacilli were classified as multidrug resistant. Tet genes were detected in 79% of isolates; the lnuA, cat, ermB, ermC, ant(6)-Ia, ant(4')-Ia, and int-Tn genes were found at a lower frequency. Sequence analysis of the quinolone resistance-determining region (QRDR)of the gyrA gene showed that fluoroquinolone resistance in lactobacilli was the result of a mutation that lead to a change in the amino acid sequence (Ser83→Tyr/Leu/Phe). Domesticated pigeons could be a reservoir for AMR Lactobacillus strains and AMR genes.

Evaluation of the ability of colistin, amoxicillin (components of Potencil® ), and fluoroquinolones to attenuate bacterial endotoxin- and Shiga exotoxin-mediated cytotoxicity-In vitro studies.

Escherichia coli is one of the major pathogens in humans and animals causing localized and systemic infections, which often lead to acute inflammation, watery diarrhea, and hemorrhagic colitis. Bacterial lipopolysaccharide (LPS) and Shiga exotoxins (Stx) are mostly responsible for such clinical signs. Therefore, highly effective treatment of E. coli infections should include both eradication of bacteria and neutralization of their toxins. Here, for the first time, we compared the in vitro ability of common antibiotics to decrease LPS- and Stx-mediated cytotoxicity: colistin, amoxicillin (used separately or combined), enrofloxacin, and its metabolite ciprofloxacin. Three experimental scenarios were realized as follows: (a) the direct effect of antibiotics on endotoxin, (b) the effect of antibiotic treatment on LPS-mediated cytotoxicity in an experiment mimicking "natural infection," (c) the effect of antibiotics to decrease Stx2e-mediated cytotoxicity. Two cell lines, A549 and Vero cells, were used to perform cytotoxic assays with the methyl tetrazolium (MTT) and lactate dehydrogenase leakage (LDH) methods, respectively. Colistin and amoxicillin, especially used in combination, were able to attenuate LPS toxic effect, which was reflected by increase in A549 cell viability. In comparison with other antibiotics, the combination of colistin and amoxicillin exhibited the highest boster or additive effect in protecting cells against LPS- and Stx2e-induced toxicity. In summary, in comparison with fluoroquinolones, the combination of colistin and amoxicillin at concentrations similar to those achieved in plasma of treated animals exhibited the highest ability to attenuate LPS- and Stx2e-mediated cytotoxicity.

Identification and antibiotic susceptibility of lactobacilli isolated from turkeys.

BACKGROUND: The aim of this study was to identify Lactobacillus isolates derived from turkeys from six Polish farms and to characterize their phenotypic and genotypic antibiotic resistance profiles. RESULTS: Among 62 isolates identified by MALDI-TOF mass spectrometry and restriction analysis of 16S rDNA, the dominant species was L. salivarius (35%), followed by L. crispatus (21%), L. ingluviei (14.5%) and L. johnsonii (10%). A high prevalence of resistance to tetracycline (68% resistant isolates), lincomycin (64.5%) and enrofloxacin (60%) among the lactobacilli tested was observed. Fewer than 50% isolates were resistant to ampicillin (47%), erythromycin (45%), streptomycin (31%), chloramphenicol (29%) and gentamicin (10%). As many as 64,5% of the isolates showed multidrug resistance. High MIC values for ampicillin (≥64 µg/ml) were usually accompanied by elevated MICs for cephalosporins (≥16 µg/ml) and high MICs for tiamulin, i.e. ≥32 µg/ml, were noted in most of the turkey lactobacilli (61%). The occurrence of resistance genes was associated with phenotypic resistance, with the exception of five phenotypically susceptible isolates that contained the tetM, tetL, ermC, ermB or cat genes. The most frequently identified were ermB (45% isolates), tetL (40%), tetW (37%) and tetM (29%), and the occurrence of lnuA (18%), cat (10%), ermC (6%), ant(6)-Ia (5%) and aadE (5%) was less frequent. The mechanism of ampicillin resistance has not been elucidated, but the results of nitrocefin test confirmed that it is not involved in the production of beta-lactamases. CONCLUSIONS: The high rate of antibiotic resistance observed in this study indicates the need to implement the principles of rational use of antibiotics in poultry. The presence of transmissible resistant genes in lactobacilli may contribute to the development of antibiotic resistant pathogenic strains that pose a threat to both poultry and consumers. The results of these studies may be useful for committees providing guidance on antibiotic susceptibility of microorganisms in order to revise and supplement current microbiological cut-offs values within the genus Lactobacillus.

Association Between the Methicillin Resistance of Staphylococcus aureus Isolated from Slaughter Poultry, Their Toxin Gene Profiles and Prophage Patterns.

In this work, 85 strains of Staphylococcus aureus were isolated from samples taken from slaughter poultry in Poland. Attempts were made to determine the prophage profile of the strains and to investigate the presence in their genome of genes responsible for the production of five classical enterotoxins (A-E), toxic shock syndrome toxin (TSST-1), exfoliative toxins (ETA and ETB) and staphylokinase (SAK). For this purpose, multiplex PCR was performed using primer-specific pairs for targeted genes. The presence of the mecA gene was found in 26 strains (30.6%). The genomes of one of the methicillin-resistant S. aureus (MRSA) strains and two methicillin-sensitive S. aureus (MSSA) strains contained the gene responsible for the production of enterotoxin A. Only one MRSA strain and two MSSA strains showed the presence of the toxic shock syndrome toxin (tst) gene. Only one of the MSSA strains had the gene (eta) responsible for the production of exfoliative toxins A. The presence of the staphylokinase gene (sak) was confirmed in 13 MRSA strains and in 5 MSSA strains. The study results indicated a high prevalence of prophages among the test isolates of Staphylococcus aureus. In all, 15 prophage patterns were observed among the isolates. The presence of 77-like prophages incorporated into bacterial genome was especially often demonstrated. Various authors emphasize the special role of these prophages in the spread of virulence factors (staphylokinase, enterotoxin A) not only within strains of the same species but also between species and even types of bacteria.

Bacteriophage therapy to combat bacterial infections in poultry.

Infections in poultry are an economic and health problem in Europe and worldwide. The most common infections are associated with salmonellosis, colibacillosis, campylobacteriosis, and others. The prevalence of Campylobacter-positive poultry flocks in European countries varies from 18% to 90%. In the United States, the prevalence of infected flocks is nearly 90%. A similar percentage of infection has been noted for salmonellosis (about 75-90%) and E. coli (90-95%). The occurence of Clostridium perfringens is a major problem for the poultry industry, with some estimates suggesting colonization of as many as 95% of chickens, resulting in clinical or subclinical infections. In the US, annual economic losses due to Salmonella infections run from $1.188 billion to over $11.588 billion, based on an estimated 1.92 million cases. Similar costs are observed in the case of other types of infections. In 2005 economic losses in the the poultry industry due to mortalities reached 1,000,000 USD.Infections caused by these pathogens, often through poultry products, are also a serious public health issue.The progressive increase in the number of multi-drug resistant bacteria and the complete ban on the use of antibiotics in livestock feed in the EU, as well as the partial ban in the US, have led to the growth of research on the use of bacteriophages to combat bacterial infections in humans and animals.The high success rate and safety of phage therapy in comparison with antibiotics are partly due to their specificity for selected bacteria and the ability to infect only one species, serotype or strain. This mechanism does not cause the destruction of commensal bacterial flora. Phages are currently being used with success in humans and animals in targeted therapies for slow-healing infections. They have also found application in the US in eliminating pathogens from the surface of foods of animal and plant origin. At a time of growing antibiotic resistance in bacteria and the resulting restrictions on the use of antibiotics, bacteriophages can provide an alternative means of eliminating pathogens.

16S-ARDRA and MALDI-TOF mass spectrometry as tools for identification of Lactobacillus bacteria isolated from poultry.

BACKGROUND: The objective of our study is to evaluate the potential use of Amplified 16S Ribosomal DNA Restriction Analysis (16S-ARDRA) and MALDI-TOF mass spectrometry (MS) as methods for species identification of Lactobacillus strains in poultry. RESULTS: A total of 80 Lactobacillus strains isolated from the cloaca of chicken, geese and turkeys were identified to the species level by MALDI-TOF MS (on-plate extraction method) and 16S-ARDRA. The two techniques produced comparable classification results, some of which were additionally confirmed by sequencing of 16S rDNA. MALDI-TOF MS enabled rapid species identification but produced more than one reliable identification result for 16.25 % of examined strains (mainly of the species L. johnsonii). For 30 % of isolates intermediate log(scores) of 1.70-1.99 were obtained, indicating correct genus identification but only presumptive species identification. The 16S-ARDRA protocol was based on digestion of 16S rDNA with the restriction enzymes MseI, HinfI, MboI and AluI. This technique was able to distinguish 17 of the 19 Lactobacillus reference species tested and enabled identification of all 80 wild isolates. L. salivarius dominated among the 15 recognized species, followed by L. johnsonii and L. ingluviei. CONCLUSIONS: The MALDI-TOF MS and 16S-ARDRA assays are valuable tools for the identification of avian lactobacilli to the species level. MALDI-TOF MS is a fast, simple and cost-effective technique, and despite generating a high percentage of results with a log(score) <2.00, the on-plate extraction method is characterized by high-performance. For samples for which Biotyper produces more than one reliable result, MALDI-TOF MS must be used in combination with genotypic techniques to achieve unambiguous results. 16S-ARDRA is simple, repetitive method with high power of discrimination, whose sole limitation is its inability to discriminate between species with very high 16S rDNA sequence homology, such as L. casei and L. zeae. The assays can be used for discrimination of Lactobacillus bacteria from different habitats.

Heat shock protein 70 and nitric oxide concentrations in non-tumorous and neoplastic canine mammary tissues: preliminary results - Short communication.

The concentrations of heat shock protein 70 (Hsp70) and nitric oxide ions (NO), measured as nitrite, were determined in canine mammary tumours and nontumorous mammary gland tissues. The concentrations of Hsp70 and NO were significantly higher in both benign and malignant tumours than in non-tumorous mammary tissues. Hsp70 concentration decreased with the increase in the grade of histological malignancy. A strong positive correlation was found between the concentrations of Hsp70 and NO in the benign tumours as well as in grade I and grade II malignant tumours. The results indicate that the process of neoplastic transformation in the canine mammary gland is related to a significant increase in Hsp70 and NO concentration in tumour tissues, and an interdependence between Hsp70 and nitrite ion production can be observed.

Screening of Lactobacillus strains of domestic goose origin against bacterial poultry pathogens for use as probiotics.

Lactobacilli are natural inhabitants of human and animal mucous membranes, including the avian gastrointestinal tract. Recently, increasing attention has been given to their probiotic, health-promoting capacities, among which their antagonistic potential against pathogens plays a key role. A study was conducted to evaluate probiotic properties of Lactobacillus strains isolated from feces or cloacae of domestic geese. Among the 104 examined isolates, previously identified to the species level by whole-cell matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and analysis of 16S-23S regions of rDNA, dominated Lactobacillus salivarius (35%), followed by Lactobacillus johnsonii (18%) and Lactobacillus ingluviei (11%). All lactobacilli were screened for antimicrobial activity toward Salmonella Enteritidis, Escherichia coli, Clostridium perfringens, Staphylococcus aureus, Pasteurella multocida, and Riemerella anatipestifer using the agar slab method and the well diffusion method. Lactobacillus salivarius and Lactobacillus plantarum exhibited particularly strong antagonism toward all of the indicator strains. In the agar slab method, the highest sensitivity to Lactobacillus was observed in R. anatipestifer and P. multocida, and the lowest in E. coli and S. aureus. The ability to produce H2O2was exhibited by 92% of isolates, but there was no correlation between the rate of production of this reactive oxygen species and the antimicrobial activity of Lactobacillus sp. All lactobacilli showed resistance to pH 3.0 and 3.5 and to 2% bile. The data demonstrate that Lactobacillus isolates from geese may have probiotic potential in reducing bacterial infections. The antibacterial activity of the selected lactobacilli is mainly due to lactic acid production by these bacteria. The selected Lactobacillus strains that strongly inhibited the growth of pathogenic bacteria, and were also resistant to low pH and bile salts, can potentially restore the balance of intestinal microflora in geese and could offer an alternative to antibiotic therapy.

Lameness in Cattle-Etiopathogenesis, Prevention and Treatment.

The aim of this review was to analyse the health problem of lameness in dairy cows by assessing the health and economic losses. This review also presents in detail the etiopathogenesis of lameness in dairy cattle and examples of its treatment and prevention. This work is based on a review of available publications. In selecting articles for the manuscript, the authors focused on issues observed in cattle herds during their clinical work. Lameness in dairy cattle is a serious health and economic problem around the world. Production losses result from reduced milk yield, reduced feed intake, reproductive disorders, treatment costs, and costs associated with early culling. A significant difficulty in the control and treatment of lameness is the multifactorial nature of the disease; causes may be individual or species-specific and may be associated with the environment, nutrition, or the presence of concomitant diseases. An important role is ascribed to infectious agents of both systemic and local infections, which can cause problems with movement in animals. It is also worth noting the long treatment process, which can last up to several months, thus significantly affecting yield and production. Given the high economic losses resulting from lameness in dairy cows, reaching even >40% (depending on the scale of production), there seems to be a need to implement extensive preventive measures to reduce the occurrence of limb infections in animals. The most important effective preventive measures to reduce the occurrence of limb diseases with symptoms of lameness are periodic hoof examinations and correction, nutritional control, and bathing with disinfectants. A clean and dry environment for cows should also be a priority.

Bacteriophages for Controlling Staphylococcus spp. Pathogens on Dairy Cattle Farms: In Vitro Assessment.

Pathogenic Staphylococcus spp. strains are significant agents involved in mastitis and in skin and limb infections in dairy cattle. The aim of this study was to assess the antibacterial effectiveness of bacteriophages isolated from dairy cattle housing as potential tools for maintaining environmental homeostasis. The research will contribute to the use of phages as alternatives to antibiotics. The material was 56 samples obtained from dairy cows with signs of limb and hoof injuries. Staphylococcus species were identified by phenotypic, MALDI-TOF MS and PCR methods. Antibiotic resistance was determined by the disc diffusion method. Phages were isolated from cattle housing systems. Phage activity (plaque forming units, PFU/mL) was determined on double-layer agar plates. Morphology was examined using TEM microscopy, and molecular characteristics were determined with PCR. Among 52 strains of Staphylococcus spp., 16 were used as hosts for bacteriophages. Nearly all isolates (94%, 15/16) showed resistance to neomycin, and 87% were resistant to spectinomycin. Cefuroxime and vancomycin were the most effective antibiotics. On the basis of their morphology, bacteriophages were identified as class Caudoviricetes, formerly Caudovirales, families Myoviridae-like (6), and Siphoviridae-like (9). Three bacteriophages of the family Myoviridae-like, with the broadest spectrum of activity, were used for further analysis. This study showed a wide spectrum of activity against the Staphylococcus spp. strains tested. The positive results indicate that bacteriophages can be used to improve the welfare of cattle.

Characterization of Riemerella anatipestifer Strains Isolated from Various Poultry Species in Poland.

Riemerella anatipestifer (R. anatipestifer) is one of the common pathogens found in poultry flocks, resulting in serious economic losses for the poultry industry due to high mortality, reduced growth rate, poor feed conversion, increased condemnations, and high treatment costs. The aim of this study was to phenotypically characterize phylogenetic relationships and assess the presence of resistance gene strains of R. anatipestifer obtained from various poultry species in Poland. A total of 57 isolates of Riemerella were included in this study. A polymerase chain reaction (PCR) and matrix assisted laser desorption ionization mass spectrometry (MALDI-TOF MS) were used for identification of the strains. The phylogenetic relationship of the R. anatipestifer isolates was determined by analysing the rpoB gene sequence. The susceptibility to antibiotics was evaluated by minimum inhibitory concentration (MIC) in liquid media. All of the field strains of R. anatipestifer were grouped into one of two clades resulting from rpoB gene sequencing. High MIC50 and MIC90 values were obtained for gentamycin, amikacin, and colistin. Low MIC50 and MIC90 values were obtained for amoxicillin cefuroxime, cefoperazone, piperacillin, and trimethoprim/sulfamethoxazole. Among the resistance genes, tet(X) and ermF were identified most frequently. This is the first phenotypic characterization of R. anatipestifer strains obtained from poultry flocks in Poland.

Purification and electrophoretic characterization of bovine conglutinin.

In this study a two-stage procedure for purification of conglutinin using affinity and ion-exchange chromatography was developed. To isolate conglutinin from bovine serum, its unique ability to bind to complement component iC3b was exploited. Incubation of bovine serum with chromatographic beads (TSK, Toyopearl HW-75 F) at 37 °C allows for iC3b deposition and subsequent binding of conglutinin. A single protein fraction eluted with ethylenediaminetetraacetic acid (EDTA) was then separated on an ion-exchange column in an NaCl gradient. The purification was evaluated by SDS-PAGE and western blotting. Conglutinin analyzed by SDS-PAGE under reducing conditions showed two main bands at 41 and 47 kDa and eight weaker bands. Nonreduced conglutinin appeared as a ladder pattern composed of many fractions ranging from 34 to 630 kDa. The bands at 34, 153, 174, 247, 338 and 387 kDa displayed the highest optical density. In the native conglutinin profile four fractions were observed, and the pI of this protein was below 8.5. The presence of sugar residues in the conglutinin molecule was detected using Schiff's reagent.

Pet Reptiles in Poland as a Potential Source of Transmission of Salmonella.

Reptiles are considered a potential source of Salmonella transmission to humans. The aim of this research was to determine the incidence of Salmonella in pet reptiles in Poland and to examine Salmonella isolates with regard to their biochemical characteristics, serotype, antimicrobial susceptibility, and pathogenic and zoonotic potential. The research material consisted of 67 reptile faeces samples. The taxonomic affiliation of the Salmonella isolates was determined by MALDI-TOF mass spectrometry, biochemical analyses, and serotyping; whole genome sequencing (WGS) analysis was performed on three isolates whose serotype could not be determined by agglutination. The antimicrobial susceptibility of the Salmonella isolates was determined by the broth dilution method, and in the case of some antimicrobials by the disk diffusion method. The pathogenic and zoonotic potential of the identified serotypes was estimated based on available reports and case studies. The presence of Salmonella was confirmed in 71.6% of faecal samples, with the highest incidence (87.1%) recorded for snakes, followed by lizards (77.8%) and turtles (38.9%). All isolates (n = 51) belonged to the species S. enterica, predominantly to subspecies I (66.7%) and IIIb (25.5%). Among these, 25 serotypes were identified, including 10 that had previously been confirmed to cause reptile-associated salmonellosis (RAS). Salmonella isolates were susceptible to all antimicrobial substances used except streptomycin, to which 9.8% of the strains showed resistance. None of the strains contained corresponding resistance genes. The study demonstrates that pet reptiles kept in Poland are a significant reservoir of Salmonella and contribute to knowledge of the characteristics of reptilian Salmonella strains. Due to the risk of salmonellosis, contact with these animals requires special hygiene rules.

Virulence Profiles and Antibiotic Susceptibility of Escherichia coli Strains from Pet Reptiles.

Exotic reptiles are increasingly being bred as pets in many countries around the world, including Poland. However, the close contact between reptiles and their owners provides favourable conditions for the transmission of zoonotic pathogens. In this work, we examined E. coli isolates from 67 captive reptiles regarding their virulence, antibiotic susceptibility, phylogenetic affiliation, and genetic diversity. The incidence of E. coli was highest in snakes (51.6%, 16 isolates/31 samples), and slightly lower in turtles (44.4%, 8/18) and lizards (44.4%, 8/18). Genes encoding virulence factors were confirmed in 50% of isolates and the most common were the traT (37.5%, n = 12), fyuA (21.87%, n = 7), and irp-2 (15.62%, n = 5). The majority (71.87%, n = 23) of E. coli isolates were susceptible to all of the antimicrobial substances used in the study. Streptomycin resistance (21.87%, n = 7) was the most frequent, while resistance to other antimicrobial substances was sporadic. One strain (3.12%) was classified as multidrug-resistant. The presence of resistance genes (aadA, tetA, tetB, tetM, and blaTEM) was confirmed in 12.5% (n = 4) of the isolates. The majority (65.6%, n = 21) of E. coli isolates represented the B1 phylogenetic group. (GTG)5-PCR fingerprinting showed considerable genetic variation in the pool of tested isolates. The frequency of E. coli in reptiles is much lower than in mammals or birds. Due to the presence of virulence genes, characteristic of both intestinal pathogenic E. coli (IPEC) and extraintestinal pathogenic E. coli (ExPEC), reptilian strains of E. coli have pathogenic potential, and therefore people in contact with these animals should follow good hygiene practices.

Antimicrobial Resistance and Virulence Genes in Staphylococci Isolated from Aviary Capercaillies and Free-living Birds in South-eastern Poland.

Introduction: The current study characterises Staphylococcus bacteria recovered from dead free-living birds and captive capercaillies kept in south-eastern Poland. The results provide novel information about the antimicrobial resistance phenotype/genotype and the virulence profile of these bacteria. Material and Methods: Samples of internal organs were taken from dead birds. Staphylococcus strains were identified by matrix-assisted laser desorption/ionisation-time-of-flight mass spectrometry. Susceptibility to 13 antibiotics was tested using a standard disc diffusion method on Mueller-Hinton agar. All isolates were screened for the presence of antibiotic resistance genes and staphylococcal enterotoxins (A to E), toxic shock syndrome toxin 1, exfoliative toxins A and B and Panton-Valentine leukocidin. Results: A total of 129 bacterial strains belonging to 19 species of the Staphylococcus genus were isolated. A relatively high percentage of them resisted fluoroquinolones, tetracyclines, macrolides and ß-lactams to a significant degree and harboured the tetK, tetM, ermC, mphC and mecA genes. Strains of the coagulase-negative S. sciuri, S. xylosus and S. cohnii were isolated with genes encoding enterotoxin A and toxic shock syndrome toxin. Conclusion: Both coagulase-positive and coagulase-negative staphylococci isolated from aviary capercaillies and free-living birds have significant pathogenic potential, and greater attention must be paid to the coagulase-negative species, which are still often considered mere contaminants. Virulence factors associated with resistance to antimicrobials, this being multiple in some strains, seem most important because they can be easily transferred between animals, especially those living in a given area.

Antibiotic Resistance in Bacteria-A Review.

BACKGROUND: A global problem of multi-drug resistance (MDR) among bacteria is the cause of hundreds of thousands of deaths every year. In response to the significant increase of MDR bacteria, legislative measures have widely been taken to limit or eliminate the use of antibiotics, including in the form of feed additives for livestock, but also in metaphylaxis and its treatment, which was the subject of EU Regulation in 2019/6. Numerous studies have documented that bacteria use both phenotypis and gentic strategies enabling a natural defence against antibiotics and the induction of mechanisms in increasing resistance to the used antibacterial chemicals. The mechanisms presented in this review developed by the bacteria have a significant impact on reducing the ability to combat bacterial infections in humans and animals. Moreover, the high prevalence of multi-resistant strains in the environment and the ease of transmission of drug-resistance genes between the different bacterial species including commensal flora and pathogenic like foodborne pathogens (E. coli, Campylobacter spp., Enterococcus spp., Salmonella spp., Listeria spp., Staphylococcus spp.) favor the rapid spread of multi-resistance among bacteria in humans and animals. Given the global threat posed by the widespread phenomenon of multi-drug resistance among bacteria which are dangerous for humans and animals, the subject of this study is the presentation of the mechanisms of resistance in most frequent bacteria called as "foodborne pathoges" isolated from human and animals. In order to present the significance of the global problem related to multi-drug resistance among selected pathogens, especially those danger to humans, the publication also presents statistical data on the percentage range of occurrence of drug resistance among selected bacteria in various regions of the world. In addition to the phenotypic characteristics of pathogen resistance, this review also presents detailed information on the detection of drug resistance genes for specific groups of antibiotics. It should be emphasized that the manuscript also presents the results of own research i.e., Campylobacter spp., E. coli or Enetrococcus spp. This subject and the presentation of data on the risks of drug resistance among bacteria will contribute to initiating research in implementing the prevention of drug resistance and the development of alternatives for antimicrobials methods of controlling bacteria.

Determination of Anti-phage Antibodies in Calf Sera Following Application of Escherichia Coli and Mannheimia Haemolytica-specific Bacteriophages.

Introduction: The widespread occurrence of drug-resistant bacteria has increased interest in alternatives to antibiotics for combatting bacterial infections, among which bacteriophages play an important role. The ability of phage proteins to induce an anti-phage immune response can significantly limit the effectiveness of treatment, which was the basis for the study described in this article. The aim of the study was to assess the effects of bacteriophages on the induction of an anti-phage humoral response in calves. Material and Methods: The study was conducted using phage components of experimental preparations and sera from calves treated and not treated with phages. Levels of G, M and A immunoglobulins were analysed by ELISA. The assay plates were coated with whole Escherichia coli and Mannheimia haemolytica phages and selected phage proteins obtained in sodium dodecyl sulphate-polyacrylamide gel electrophoresis and two-dimensional electrophoresis. Neutralisation of phages by immunoglobulins was assessed by determining phage titres using double-layer plates. Results: The results confirmed an increased anti-phage response affecting all immunoglobulin classes in the calf sera. The highest significant (P ≤ 0.05) level of antibodies was observed for IgG in the sera of calves receiving phages. The phage neutralisation test showed a significant differences (P ≤ 0.05) in the reduction of phage titres in comparison to untreated calves. Conclusion: Despite the induction of an anti-phage response, no significant negative effect on the antibacterial activity of phages was observed in vitro.

Experimental Phage Therapies in Companion Animals with A Historical Review.

BACKGROUND: The aim of the review was to comprehensively characterize the antimicrobial efficacy of bacteriophages in eliminating pathogens occurring in companion animals, as an alternative to antibiotics for controlling infections that pose potential threats to the health and life of people and to the environment. METHODS: The review contains detailed information on the characteristics and classification of bacteriophages and an analysis of their life cycle. The dominant element is a detailed analysis of the experimental use of bacteriophages in combating infections caused by various microorganisms in companion animals with regard to their potential use in therapy. RESULTS: It seems that in the near future, phage therapies will provide an alternative to antibiotics in the treatment of diseases caused by multi-drug resistant bacteria in people and animals. CONCLUSIONS: The effectiveness of phage therapies depends on many factors and the properties of the bacteriophages themselves, which requires comprehensive knowledge of them.

Bacteriophages as an Alternative Method for Control of Zoonotic and Foodborne Pathogens.

The global increase in multidrug-resistant infections caused by various pathogens has raised concerns in human and veterinary medicine. This has renewed interest in the development of alternative methods to antibiotics, including the use of bacteriophages for controlling bacterial infections. The aim of this review is to present potential uses of bacteriophages as an alternative to antibiotics in the control of bacterial infections caused by multidrug-resistant bacteria posing a risk to humans, with particular emphasis on foodborne and zoonotic pathogens. A varied therapeutic and immunomodulatory (activation or suppression) effect of bacteriophages on humoral and cellular immune response mechanisms has been demonstrated. The antibiotic resistance crisis caused by global antimicrobial resistance among bacteria creates a compelling need for alternative safe and selectively effective antibacterial agents. Bacteriophages have many properties indicating their potential suitability as therapeutic and/or prophylactic agents. In many cases, bacteriophages can also be used in food quality control against microorganisms such as Salmonella, Escherichia coli, Listeria, Campylobacter and others. Future research will provide potential alternative solutions using bacteriophages to treat infections caused by multidrug-resistant bacteria.