Bacteria from the species Trueperella pyogenes are a part of the biota of skin and mucous membranes of the upper respiratory, gastrointestinal, or urogenital tracts of animals, but also, opportunistic pathogens. T. pyogenes causes a variety of purulent infections, such as metritis, mastitis, pneumonia, and abscesses, which, in livestock breeding, generate significant economic losses. Although this species has been known for a long time, many questions concerning the mechanisms of infection pathogenesis, as well as reservoirs and routes of transmission of bacteria, remain poorly understood. Pyolysin is a major known virulence factor of T. pyogenes that belongs to the family of cholesterol-dependent cytolysins. Its cytolytic activity is associated with transmembrane pore formation. Other putative virulence factors, including neuraminidases, extracellular matrix-binding proteins, fimbriae, and biofilm formation ability, contribute to the adhesion and colonization of the host tissues. However, data about the pathogen–host interactions that may be involved in the development of T. pyogenes infection are still limited. The aim of this review is to present the current knowledge about the pathogenic potential and virulence of T. pyogenes.

This study was performed in order to isolate lactobacilli from chicken droppings and to select strains with the most promising probiotic properties. Lactobacillus strains were isolated from a flock of healthy laying hens. The first selection criterion was the ability to inhibit the growth of Salmonella Enteritidis. Then the tolerance to low pH and bile salt, the ability to coaggregate with pathogenic bacteria and hydrogen peroxide production were evaluated. Four isolates showing the best antagonistic activity against Salmonella Enetritidis were selected for further research. All isolates tested tolerated low pH and bile salt, likewise all produced hydrogen peroxide. They efficiently coaggregated with C. perfringens and relatively less with E. coli. Isolate 03’04 displayed above-average results in all criteria, thus it is considered as a potential probiotic for chickens, and will be further evaluated for health promoting effect in animals. The results presented in this study confirm the strain specific probiotic properties and prove the probiotic potential of isolate 03’04. Strong antagonistic properties against C. perfringens exhibited by certain Lactobacillus strains indicate the possibility to use them as a component of probiotic supplement in necrotic enteritis of poultry.

The purpose of the study was to examine of bacteria present in chicken embryos and newly hatched chicks. The bacteria were determined quantitatively in caecal contents, liver and yolk sac of 25 embryos at 18 day of incubation, 25 embryos at 20 day incubation, and 25 newly hatched chicks....

Rhodococcus equi is an emerging zoonotic presumably foodborne pathogen. Since the data on the worldwide prevalence of R. equi in meat animals are scarce, the present study aimed to investigate the molecular epidemiology of R. equi in swine, cattle and horse carcasses intended for human consumption in Poland. Totally 1028 lymph node samples were examined. R. equi was isolated from 26.6 % (105/395) swine and 1.3 % (3/234) bovine healthy submaxillary lymph nodes. In horses, R. equi was isolated only from 0.5 % (1/198) samples of middle tracheo-branchiales lymph node while no lymphocentrum retropharyngeum sample was positive (0/198). The purulent lesions were observed only in 0.8 % swine submaxillary lymph nodes samples (3/398) and in two of them R. equi was detected. All bovine and most of swine isolates (98.1 %) were vapB-positive. 87.9 % of swine isolates carried 95-kb type 5 plasmid, 3.7 % type 1 and plasmid types: 4, 7, 10, 11, 21, 31 were carried by a single isolate (0.9 %). All bovine isolates carried VAPB type 26. Single horse isolate was vapA-positive and carried plasmid VAPA 85-kb type I. The prevalence of vapB-positive R. equi in investigated healthy swine intended for human consumption was very high. Not only swine, but also even apparently healthy cattle or horse carcasses should be considered as a potential source of R. equi for humans, especially in countries where undercooked or raw beef or horsemeat is traditionally consumed.

Mupirocin is one of the few antimicrobials active against methicillin-resistant Staphylococcus aureus (MRSA), and is frequently used for the eradication of MRSA nasal colonisation in humans. Initially, mupirocin resistance was recognised in human S. aureus, including MRSA isolates, then also among coagulase-negative staphylococci (CoNS). Nowadays, mupirocin resistance is occasionally observed in canine staphylococci, along with Staphylococcus pseudintermedius (MRSP) strains, as well as CoNS, which usually show methicillin resistance. In the current study, high-level mupirocin resistance in methicillin-resistant staphylococci isolated from diseased dogs and cats was investigated. Among 140 methicillin-resistant staphylococci isolates from dogs and cats, three showed high-level mupirocin resistance in a screening test using the agar disk diffusion method. One was recognised as methicillin-resistant S. aureus, one as methicillin-resistant S. pseudintermedius, and one as methicillin-resistant Staphylococcus haemolyticus. S. pseudintermedius and S. aureus were isolated from dogs, S. haemolyticus was obtained from a cat. All isolates showed high-level mupirocin resistance, confirmed by minimum inhibitory concentration (MIC) values of above 1024 μg/ml and the presence of the plasmid-located gene ileS2. This is the first report on the detection of high-level mupirocin resistance (HLMR) in S. haemolyticus of feline origin. This study revealed the occurrence of HLMR in three Staphylococcus isolates obtained from companion animals in Poland. The results of this study indicate that the monitoring of mupirocin resistance in staphylococci of animal origin, especially in methicillin-resistant isolates, is strongly recommended.