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The species Lactococcus lactis is a bacterium extensively used in the dairy industry. This bacterium is Generally Recognized as Safe and was added to the European Food Safety Authority's Qualified Presumption of Safety list. The major functions of this species in dairy fermentation are the production of lactic acid from lactose, citric acid fermentation, and the hydrolysis of casein. But, the representatives of this species that produce bacteriocin substances can also exert an inhibitory effect against spoilage bacteria. The aims of this study were to test three lactococcal strains isolated from raw goat milk for their postbiotic activity and to test their stability in goat milk yogurts after their application in encapsulated form for their further application. To achieve these aims, validated methods were used. Three Lactococcus lactis strains (identified by Blastn 16S rRNA analysis) produced bacteriocin substances/postbiotics. These concentrated postbiotics inhibited the growth of enterococci and staphylococci (by up to 97.8%), reaching an inhibitory activity of up to 800 AU/mL. The encapsulated (freeze-dried) lactococci survived in the goat milk yogurts with sufficient stability. Strain MK2/8 fortified the yogurts in the highest amount (8.1 ± 0.0 cfu/g log 10). It did not influence the pH of the yogurt. [ABSTRACT FROM AUTHOR]

For several years, alpha klotho has been considered as a candidate biomarker in chronic kidney disease (CKD), progression of CKD and CKD mineral bone disorders (CKD-MBD). The evidence on the relationship between klotho and kidney function is controversial in some areas. The aim of the study was to identify the influence of age, sex and breed on urinary alpha klotho, values in the early stages of CKD within the studied population and determine a reference interval in a group of healthy dogs. Significantly higher values were measured in older dogs over 6 years old (p = 0.026, p = 0.0007) and in the breed German Shepherd than Belgian Shepherd (p = 0.0401). On the basis of sex and in small breed dogs, no significant differences were noted. In dogs with CKD stage 2, alpha klotho values were significantly lower (p = 0.0135) than in healthy dogs. Within the studied population, a reference interval for urinary klotho to creatinine ratio (UrKl/Cr) was determined in the range of 3.94–23.55 pg/gCr. Since our findings show that alpha klotho is associated with older age, we assume that this may have influenced the results in the group of dogs with CKD stage 1 due to the presence of predominantly old dogs in this group. Future studies would be needed to consider age as a factor affecting urinary alpha klotho in dogs with CKD. [ABSTRACT FROM AUTHOR]

Simple Summary: Simple Summary: Uromodulin has been known for many years as a normal protein component of urine. However, in recent years, serum as well as urinary uromodulin have been investigated in relation to kidney diseases. Chronic kidney disease (CKD) is a common diagnosis, especially in old dogs, and suitable markers for the early stages of the disease are constantly being investigated. We focused on the effect of age and gender on uromodulin in serum and urine in a healthy population of dogs of the same breed, German shepherd. We compared the results with two groups of other breeds of healthy dogs. Compared with groups of patients in the early stages of CKD, we concluded that urinary uromodulin corrected to creatinine in urine seems to be the most prospective marker. Serum and urinary uromodulin are evaluated as potential biomarkers of kidney disease. The aim of our research was to select a more appropriate form of uromodulin for the diagnosis of early stages of chronic kidney disease (CKD). We also focused on the influence of age and gender in one breed on uromodulin and on the possible interbreed differences. Serum uromodulin had the lowest values in dogs younger than 2 years but no effect of gender, breed, or CKD was observed. Urinary uromodulin indexed to urinary creatinine was significantly reduced in dogs in stage 2 of CKD (p = 0.003) in contrast to uromodulin converted to urine specific gravity. Urinary uromodulin with both corrections was significantly lower in Belgian shepherds compared to German shepherds (p < 0.0001, p = 0.0054) but was not influenced by gender or age. In stage 1 of CKD, urinary uromodulin correlated with kidney disease markers SDMA (p = 0.0424, p = 0.0214) and UPC (p = 0.0050, p = 0.0024). Urinary uromodulin appears to be more associated with CKD than serum uromodulin. Further studies with a larger number of patients are needed for the suitability of urinary uromodulin as a marker of early-stage disease. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the antimicrobial and antibiofilm activity of Weissella cibaria, Weissella hellenica and Bacillus coagulans, isolated from equine skin, against biofilm-forming Staphylococcus aureus CCM 4223 and clinical isolate methicillin-resistant S. aureus (MRSA). Non-neutralized cell-free supernatants (nnCFS) of tested skin isolates completely inhibited the growth and biofilm formation of S. aureus strains and caused dispersion of the 24 h preformed biofilm in the range of 21–90%. The majority of the pH-neutralized cell-free supernatants (nCFS) of skin isolates inhibited the biofilm formation of both S. aureus strains in the range of 20–100%. The dispersion activity of B. coagulans nCFS ranged from 17 to 77% and was significantly lower than that of nnCFS, except for B. coagulans 3T27 against S. aureus CCM 4223. Changes in the growth of S. aureus CCM 4223 in the presence of catalase- or trypsin-treated W. hellenica 4/2D23 and W. cibaria 4/8D37 nCFS indicated the role of peroxides and/or bacteriocin in their antimicrobial activities. For the first time, the presence of the fenD gene, associated with biosurfactants production, was detected in B. coagulans. The results of this study showed that selected isolates may have the potential for the prevention and treatment of biofilm-forming S. aureus infections. [ABSTRACT FROM AUTHOR]

Simple Summary: Periodontal disease represents a worldwide health problem. Human periodontal pathogens such as Treponema denticola, Porphyromonas gingivalis, Tannerella forsythia and Aggregatibacter actinomycetemcomitans are the cause of inflammatory response resulting in periodontitis. Porphyromonas gulae is mostly involved in periodontitis in dogs; however, it is not a common pathogen in humans. This study deals with the prevalence of periodontal pathogens in Slovak patients with periodontitis. Furthermore, based on the previous findings of animal-to-human transmission of periodontal pathogens, this study also assesses the possible bacterial transmission between animals and their owners. The highest prevalence in Slovak patients amongst the monitored periodontal pathogens had T. forsythia. In regard to the limited information available on T. forsythia, antibiotic sensitivity of this bacterium was evaluated. Most of the T. forsythia isolates were susceptible to antibiotics, namely amoxicillin-clavulanic acid, clindamycin and moxifloxacin, while they were resistant to metronidazole. Moreover, the transmission of P. gulae between animals and their owners was confirmed. Based on the similarity of P. gulae with human P. gingivalis, there arises the question as to whether P. gulae can also be involved in the periodontitis pathogenesis in humans. However, more studies are required for further clarification. Oral health and diseases are greatly influenced by oral bacteria. During dysbiosis, bacterial composition changes, which can lead to periodontitis. Periodontitis in humans is associated with periodontal pathogens such as Treponema denticola, Porphyromonas gingivalis, Tannerella forsythia and Aggregatibacter actinomycetemcomitans. Animal-to-human transmission of some of these pathogens has also been reported. The aim of this study was to evaluate the prevalence of periodontal pathogens in Slovak patients and to assess the possible risk of transmission of these pathogens from animals to their owners. The presence of periodontal pathogens in dental plaque was monitored by PCR. Amplified products were analysed using Sanger sequencing. T. forsythia isolates were assessed for the susceptibility to different antibiotics using the disk diffusion method. In humans, T. denticola, P. gingivalis, T. forsythia and A. actinomycetemcomitans were present in 69.23%, 69.23%, 100% and 84.62%, respectively. Most isolates of T. forsythia were susceptible to amoxicillin-clavulanic acid, clindamycin and moxifloxacin, but they were resistant to metronidazole. The transmission of T. forsythia from animals to their owners was not proven based on sequence analysing. On the other hand, transmission of Porphyromonas gulae was confirmed, but the risk of its involvement in the pathogenesis of periodontitis in humans must be further investigated. [ABSTRACT FROM AUTHOR]

Bacillus licheniformis is used in a broad spectrum of areas, including some probiotic preparations for human and veterinary health. Moreover, B. licheniformis strains are known producers of various bioactive substances with antimicrobial and antibiofilm effects. In searching for new potentially beneficial bacteria for oral health, the inhibitory effect of B. licheniformis strains isolated from canine dental biofilm against pathogenic oral bacteria was evaluated. The antimicrobial effect of neutralized cell-free supernatants (nCFS) was assessed in vitro on polystyrene microtiter plates. Furthermore, molecular and morphological analyses were executed to evaluate the production of bioactive substances. To determine the nature of antimicrobial substance present in nCFS of B. licheniformis A-1-5B-AP, nCFS was exposed to the activity of various enzymes. The nCFS of B. licheniformis A-1-5B-AP significantly (p < 0.0001) reduced the growth of Porphyromonas gulae 3/H, Prevotella intermedia 1/P and Streptococcus mutans ATCC 35668. On the other hand, B. licheniformis A-2-11B-AP only significantly (p < 0.0001) inhibited the growth of P. intermedia 1/P and S. mutans ATCC 35668. However, enzyme-treated nCFS of B. licheniformis A-1-5B-AP did not lose its antimicrobial effect and significantly (p < 0.0001) inhibited the growth of Micrococcus luteus DSM 1790. Further studies are needed for the identification of antimicrobial substances. [ABSTRACT FROM AUTHOR]

Dental plaque bacteria are one of the main factors responsible for the development of a periodontal disease, which is the most common infectious disease in dogs. The aim of this study was to identify the presence of periodontal disease-related bacteria in the dental plaque of dogs. Plaque samples were taken from dogs with and without periodontal disease. Samples were analyzed for the presence of Porphyromonas gulae, Tannerella forsythia and Treponema denticola using a PCR technique amplifying 16S rRNA genes of P. gulae and T. forsythia and flaB2 genes of Treponema species, including T. denticola. The presence of T. forsythia was confirmed in all samples. P. gulae was detected in all dogs with periodontal disease and in 71.43% of dogs without periodontal disease. Treponema spp. were detected in 64.29% of the samples. Based on Sanger sequencing and Basic Local Alignment Search Tool algorithm, Treponema spp. were identified as T. denticola and Treponema putidum. T. denticola was present in 28.57% of dogs with periodontal disease, while T. putidum was present in 42.86% of dogs with periodontal disease and in 57.14% of dogs without periodontal disease. T. putidum was positively correlated with both P. gulae and T. forsythia, suggesting that it may be involved in the development of periodontal disease. [ABSTRACT FROM AUTHOR]

The occurence and spread of animal-derived methicillin resistant staphylococci (MRS) worldwide is a current problem, especially due to their increasing incidence in food animals and their products, with possible contamination of food consumers and handlers. Staphylococci isolated from animals (n = 123) were identified with MALDI-TOF mass spectrometry and screened for methicillin/oxacillin/cefoxitin resistance (MR) using the disk diffusion method. Twenty-three phenotypically MRS strains were analysed using PBP2' Latex Agglutination Test Kit to confirm the phenotypic MR and PCR was performed for mecA gene detection; mecA gene positive strains were furtherly confirmed by means of sequencing. The susceptibility of MRS to 11 partially-purified enterocins (Ent) produced by E. faecium, E. durans and E. mundtii strains of animal, feed/food and environmental origin was checked using agar spot tests. Out of 23 MRS, PBP testing confirmed MR in 17 strains. Three Staphylococcus epidermidis and one S. vitulinus were mecA positive. The majority of MRS, including two mecA gene-positive strains S. epidermidis R44/1 and P3/Tr2a, were susceptible to the tested enterocins, mainly to Ent7420, EntA(P)/EK13, Ent412, Ent55 and Ent9296 (in the range 100 – 12,800 AU/mL). The most susceptible strains appeared to be the mecA gene-positive S. epidermidis SE R44/1 and SE P3/Tr2a strains, inhibited by eight enterocins out of 11 tested (100–200 AU/mL). Only four strains (including mecA gene positive S. epidermidis SE P3/Tr1 and S. vitulinus SV K12PL/1) were resistant to the tested antimicrobial substances. These results indicate that the enterocins used offer a promising option for prevention and treatment of bacterial infection caused by MRS in animals. [ABSTRACT FROM AUTHOR]

Dental diseases are a persistent problem, not only in humans, but very often in companion animals as well. Aetiological agents of these diseases are the dental plaque bacteria. In the present study, we focused on identifying cultivable bacteria living in the dental plaque of dogs, specifically dogs suffering from the early stages of periodontal disease. Canine oral bacteria pose a risk to humans that get bitten by the dog, but they also have a zoonotic potential. Dental plaque samples were taken from five dogs of small breeds. Samples were cultured under aerobic and anaerobic conditions on several types of microbiological agars. All obtained and selected bacterial colonies were identified by PCR with universal primers for the 16S rRNA gene and the sequences of the 16S rRNA gene were compared with the sequences available in the GenBank database using BLASTn analysis. A total of 75 bacteria belonging to five phyla, predominantly to Firmicutes and Proteobacteria, were identified. The most frequent species was Pasteurella canis which was detected in all samples. In addition, representatives of the genera Actinomyces, Bacillus, Bacteroides, Corynebacterium, Frederiksenia, Fusobacterium, Haemophilus, Lactobacillus, Leucobacter, Neisseria, Ottowia, Porphyromonas, Pseudomonas, Staphylococcus, Stenotrophomonas and Streptococcus were detected in the samples. In the present study, a broad spectrum of bacteria in dental plaque samples, including canine periodontal pathogens such as Porphyromonas gulae or Porphyromonas macacae were identified. In addition, highly pathogenic bacteria, specifically Actinomyces hordeovulneris, Bacillus circulans, and Bacteroides pyogenes, which pose a serious risk to human health, were detected in samples. [ABSTRACT FROM AUTHOR]

Introduction and objectives. The parasite Cryptosporidium spp. is an intracellular protozoa which has a broad range of hosts and zoonotic potential. It presents a serious health risk for agricultural workers and veterinarians. The aim of the study was to identify the species and subtypes of Cryptosporidium occurring in a veterinary student who came into contact with calves on a farm. Materials and method. The Ziehl-Neelsen staining technique was employed to confirm the presence of Cryptosporidium oocysts. ELISA test was applied to detect coproantigen in faecal specimens. Nested PCR was used to amplify a small ribosomal subunit (SSU rRNA) and sequencing of the GP60 gene served to identify the zoonotic subtypes. Results. The nested PCR allowed to confirm the C. parvum species; subsequently, the IIdA15G1 zoonotic subtype was identified. Conclusion. This is the first confirmed case in Slovakia of human cryptosporidiosis caused by the unique subtype IIdA15G1. [ABSTRACT FROM AUTHOR]

Biosurfactants (BSs) are surface-active compounds produced by diverse microorganisms, including the genus Bacillus. These bioactive compounds possess biological activities such as antiadhesive, antimicrobial and antibiofilm effects that can lead to important applications in combating many infections. Based on these findings, we decided to investigate the antibiofilm activity of BSs from the marine Bacillus amyloliquefaciens against Staphylococcus aureus CCM 4223. Expression of biofilm-related genes was also evaluated using qRT-PCR. Isolated and partially purified BSs were identified and characterized by molecular tools and by UHPLC-DAD and MALDI-TOF/MS. Bacillus amyloliquefaciens 3/22, that exhibited surfactant activity evaluated by oil spreading assay, was characterized using the 16S rRNA sequencing method. Screening by PCR detected the presence of the sfp, srfAA, fenD and ituD genes, suggesting production of the lipopeptides (LPs) surfactin, fengycin and iturin. The above findings were further supported by the results of UHPLC-DAD and MALDI-TOF/MS. As quantified by the crystal violet method, the LPs significantly (p < 0.001) reduced biofilm formation of S. aureus in a dose-dependent manner and decreased expression of biofilm-related genes fnbA, fnbB, sortaseA and icaADBC operon. Data from our investigation indicate a promising therapeutic application for LPs isolated from B. amyloliquefaciens toward prevention of S. aureus biofilm infections. [ABSTRACT FROM AUTHOR]

Oral probiotics are increasingly used in the harmonization of the oral microbiota in the prevention or therapy of various oral diseases. Investigation of the antimicrobial activity of the bacteriocinogenic strain Streptococcus salivarius K12 against oral pathogens shows promising results, not only in suppressing growth, but also in eliminating biofilm formation. Based on these findings, we decided to investigate the antimicrobial and antibiofilm activity of the neutralized cell-free supernatant (nCFS) of S. salivarius K12 at various concentrations against selected potential oral pathogens under in vitro conditions on polystyrene microtiter plates. The nCFS of S. salivarius K12 significantly reduced growth (p < 0.01) in Streptococcus mutans Clarke with increasing concentration from 15 to 60 mg/mL and also in Staphylococcus hominis 41/6 at a concentration of 60 mg/mL (p < 0.001). Biofilm formation significantly decreased (p < 0.001) in Schaalia odontolytica P10 at nCFS concentrations of 60 and 30 mg/mL. Biofilm inhibition (p < 0.001) was also observed in Enterobacter cloacae 4/2 at a concentration of 60 mg/mL. In Schaalia odontolytica P10 and Enterobacter cloacae 4/2, the nCFS had no effect on their growth. [ABSTRACT FROM AUTHOR]

Periodontal diseases are the most common condition in companion animal practice. The administration of antibiotics is associated with the therapy of these diseases. The aim of the present study was to verify the effect of antibiotics on canine dental biofilm bacteria due to increasing antibiotic resistance. Dental biofilm samples were taken from six dogs before and after administration of antibiotics, specifically, the combination of spiramycin and metronidazole. The samples were cultured on solid media under aerobic and anaerobic conditions. Sequencing analysis of the 16S rRNA gene was used to identify bacterial isolates. In addition, total bacterial DNA was extracted from samples from one dog and the V3−V4 region of the 16S rRNA gene was sequenced using the Illumina MiSeq platform. Using cultivation, 55 isolates belonging to 4 phyla were isolated before antibiotics administration, and 36 isolates belonging to 3 phyla were isolated after antibiotics administration. A significant decrease was noted in the genera Porphyromonas, Neisseria and Frederiksenia, whereas there was a significant increase in the genus Streptococcus. Of the total microbiota, there were 69 operational taxonomic units (OTUs) belonging to 11 phyla before antibiotics administration, and 51 OTUs belonging to 8 phyla after antibiotics administration. A significant decrease was recorded in the genus Porphyromonas, while a significant increase in the genus Capnocytophaga. The significant effect of spiramycin and metronidazole on the genus Porphyromonas at the time of their administration was confirmed by both cultivation and amplicon sequencing. [ABSTRACT FROM AUTHOR]