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Journal of Dairy Science May 2024The objective of this study was to analyze the in vitro antimicrobial resistance (AMR) of Streptococcus (Sc.) dysgalactiae, Sc. agalactiae, and Sc. canis over a 10-year...
Antimicrobial resistance of Streptococcus dysgalactiae, Streptococcus agalactiae, and Streptococcus canis in quarter milk samples from Bavaria, Southern Germany, between 2012 and 2022.
The objective of this study was to analyze the in vitro antimicrobial resistance (AMR) of Streptococcus (Sc.) dysgalactiae, Sc. agalactiae, and Sc. canis over a 10-year period from 2012 to 2022 against the most commonly used antimicrobial agents. For this purpose, all quarter milk samples (QMS) submitted to the milk laboratory of the Bavarian Animal Health Service (TGD) were analyzed. Each QMS was tested using the California Mastitis Test (CMT) and categorized as negative (N), subclinical (S), or clinical (C) mastitis if the milk character was abnormal. Samples with Sc. dysgalactiae, Sc. agalactiae, or Sc. canis were included and a subset of isolates were further tested for in vitro antimicrobial resistance by breakpoint analysis with broth microdilution. Sc. dysgalactiae (61%, n = 65,750) was the most abundant pathogen among those 3 species, followed by Sc. agalactiae (28%, n = 30,486), and Sc. canis (11%, n = 11,336). All 3 species showed the highest resistance to the same 4 antimicrobial agents: erythromycin, marbofloxacin, pirlimycin, and cefalexin/kanamycin with varying degrees of resistance. Throughout the study period, Sc. dysgalactiae, Sc. agalactiae, and Sc. canis were largely susceptible to the remaining antimicrobial agents tested (penicillin, amoxicillin-clavulanate, oxacillin, cefazolin, cefoperazone, cefquinome). Only less than 14% of isolates of Sc. dysgalactiae and Sc. canis were resistant against any of the antimicrobials tested. Sc. agalactiae was the species with the highest percentage of resistant isolates. While the percentage of resistant isolates from Sc. canis and Sc. dysgalactiae decreased, the percentage of resistant Sc. agalactiae isolates increased since 2017. In summary, most isolates were not resistant to the most commonly used antimicrobial agents for mastitis therapy, including β-lactam antibiotics and penicillin should remain the first-choice therapy against streptococcal mastitis.
PubMed: 38825124
DOI: 10.3168/jds.2023-24555 -
Theriogenology Aug 2024The vaginal microbiota of the queen (i.e., female cat) has never been described using culture independent methods. The objectives of the present research were to...
The vaginal microbiota of the queen (i.e., female cat) has never been described using culture independent methods. The objectives of the present research were to describe the vaginal microbiota of healthy domestic shorthair queens using both 16S rRNA sequencing and culture, and to assess the effects of age, living environment, and reproductive season on its composition. Thirty queens undergoing elective ovariectomy were included in the study. The vaginal samples were collected just before surgery, from animals under general anaesthesia. Two consecutive mini-swabs were introduced in the queens' vaginal tract. A preliminary study with 10 healthy queens aimed to negate sampling order's effect. Two consecutive samples for sequencing (5 queens, 10 swabs) and culture (5 queens, 10 swabs) were collected, confirming a match (100 % in culture, Bray-Curtis P = 0.96 in sequencing). The experiment included 20 queens that were prospectively grouped based on age (prepubertal N = 10, adult N = 10), living environment (indoor N = 10, outdoor N = 10), and time of the year, whether during the reproductive season (N = 10) or during seasonal anoestrous (N = 10). Bacteria were identified through metataxonomic analysis, amplifying the V1-V2 regions of 16S rRNA gene, and through standard culture followed by MALDI-TOF MS. The feline vaginal microbiota is dominated by Proteobacteria, Firmicutes, Bacteroidota, and Actinobacteria. Escherichia-Shigella, Streptococcus, and Pasteurella were the most abundant genera. Although culture underestimated bacterial richness and diversity compared to sequencing, Escherichia and Streptococcus were the most isolated bacteria. No bacterial growth was observed in 15 % of samples (N = 3/20), whereas growth of one or two bacterial species was observed in 64.7 % (N = 11/17) and 35.3 % (N = 6/17) of cases, respectively. No differences in terms of alpha (Kruskal-Wallis rank sum test P = 0.65) and beta diversity (Bray-Curtis, Unweighted and Weighted UniFrac analyses P > 0.5) were observed. Although a difference in alpha diversity based on phylogenetic tree (P = 0.02) was detected between indoor and outdoor queens. In conclusion, mixed and monoculture of Escherichia coli, Streptococcus canis, Staphylococcus felis, and Enterococcus spp. are normal findings within the cat vagina. Age and reproductive season do not influence the feline vaginal microbiota, whereas further research is needed to elucidate the role of the living environment.
Topics: Animals; Cats; Female; Vagina; Microbiota; Bacteria; RNA, Ribosomal, 16S; Seasons
PubMed: 38772246
DOI: 10.1016/j.theriogenology.2024.05.021 -
BMC Research Notes May 2024The purpose of this study was to identify the M protein trans-acting positive regulator (Mga) orthologue and its adjacent M-like protein (SCM) alleles in Streptococcus...
OBJECTIVE
The purpose of this study was to identify the M protein trans-acting positive regulator (Mga) orthologue and its adjacent M-like protein (SCM) alleles in Streptococcus canis.
RESULTS
Using the 39 SCM allele isolates and polymerase chain reaction-based amplification and sequencing, we obtained the deduced Mga amino acid (AA) sequences. The 22 Mga sequences in whole-genome sequences were obtained by searching the National Collection of Type Cultures 12,191(T) Mga sequence into the database. The percentage identity to the type-strain Mga sequence was examined along with its size. The presence of the Mga-specific motifs was confirmed. Of the 62 strains, we identified 59 Mga sequences with an AA size of 509 (except for four different sizes). Percentage identity ranged from 96.66 to 100% with the confirmed Mga-specific motifs and diverse SCM allele populations. Our findings support the presence of an Mga orthologue and diverse SCM allele populations.
Topics: Alleles; Streptococcus; Bacterial Proteins; Amino Acid Sequence
PubMed: 38750516
DOI: 10.1186/s13104-024-06795-8 -
Cureus Apr 2024Prosthetic joint infections (PJIs) are one of the most feared complications by orthopaedic surgeons. Haematogenous PJI represents an important part of PJI cases. is an...
Prosthetic joint infections (PJIs) are one of the most feared complications by orthopaedic surgeons. Haematogenous PJI represents an important part of PJI cases. is an extremely rare cause of haematogenous PJI and its medical and surgical treatment and prognosis are not well established. We present a 79-year-old female patient who had a revision total knee arthroplasty (rTKA) surgery three years before. She was admitted to the hospital referring to three days of knee pain, restricted range of motion, and fever. Blood tests demonstrated leukocyte and C-reactive protein elevation. Joint fluid aspiration showed elevated white blood cell count with a high neutrophil differential and its conventional culture was positive for . She did not have pets but she took care of her daughter's dog. An acute haematogenous infection of the rTKA was diagnosed and treated with debridement, antibiotics (eight weeks of IV ceftriaxone), and implant retention (DAIR). After one year, the patient remains clinically asymptomatic without changes on X-rays and with normal serum levels of inflammatory blood markers. has to be kept in mind as a possible cause of haematogenous TKA infection in patients who have contact with domestic pets and patients should be asked for this contact. We recommend DAIR as a viable treatment option for this type of infection, which may show excellent results.
PubMed: 38745789
DOI: 10.7759/cureus.58247 -
Microbiology Resource Announcements Jun 2024We report seven draft genome sequences of strains revealing reduced penicillin-G susceptibility. The genomes measured 2.054-2.385 Mbp, with G+C contents of 38.8%-39.6%....
We report seven draft genome sequences of strains revealing reduced penicillin-G susceptibility. The genomes measured 2.054-2.385 Mbp, with G+C contents of 38.8%-39.6%. Amino acid substitutions in penicillin-binding proteins were characterized as compared with those of NCTC 12191(T) genome sequence (GenBank accession number NZ_LR134293.1).
PubMed: 38742884
DOI: 10.1128/mra.00219-24 -
Journal of Comparative Pathology May 2024This case series describes the post-mortem findings in 17 bitches (Canis lupus familiaris) with a recent (<7 days) history of caesarean section, most (94%) of which had...
This case series describes the post-mortem findings in 17 bitches (Canis lupus familiaris) with a recent (<7 days) history of caesarean section, most (94%) of which had undergone conservative caesarean section with preservation of the uterus. Brachycephalic breeds accounted for 71% of all cases, with the French Bulldog (35%, n = 6), English Bulldog (18%, n = 3) and Boston Terrier (12%, n = 2) overrepresented. Eleven animals (65%) died between 4 and 48 h after surgery, whereas six (35%) died during the procedure. The most common cause of death was septicaemia (41%, n = 7) associated with Streptococcus canis (29%, n = 5) and/or Escherichia coli (24%, n = 4). Other causes of death included brachycephalic obstructive airway syndrome (BOAS)-associated respiratory failure (24%, n = 4), haemorrhagic shock (18%, n = 3), inconclusive (12%, n = 2) and gastric dilatation and volvulus (6%, n = 1). Histopathological changes were seen in the uterus of 10 cases and included marked inflammation (60%, n = 6), marked haemorrhage (20%, n = 2) or both (20%, n = 2). Metritis was often characterized by fibrinonecrotic, neutrophilic to mixed inflammation, consistent with acute infection. However, prominent lymphohistiocytic infiltrates in two cases suggested that infection had been present prior to surgery. Peritonitis, myositis and panniculitis commonly (35%, n = 6) surrounded the incision sites. The presence of inflammation and bacterial colonies within multiple surgical sites suggested iatrogenic implantation of bacteria, potentially from the uterine lumen. Bacterial culture and isolation, as well as tape measurements for evaluation of conformational BOAS risk factors where applicable, are recommended as part of the routine post-mortem work-up for bitches that die shortly after caesarean section.
Topics: Animals; Female; Dogs; Dog Diseases; Cesarean Section; Pregnancy
PubMed: 38636281
DOI: 10.1016/j.jcpa.2024.03.205 -
BMC Veterinary Research Apr 2024Growing antibiotic resistance has made treating otitis externa (OE) increasingly challenging. On the other hand, local antimicrobial treatments, especially those that...
BACKGROUND
Growing antibiotic resistance has made treating otitis externa (OE) increasingly challenging. On the other hand, local antimicrobial treatments, especially those that combine essential oils (EOs) with nanoparticles, tend to be preferred over systemic ones. It was investigated whether Ajwain (Trachyspermum ammi) EO, combined with chitosan nanoparticles modified by cholesterol, could inhibit the growth of bacterial pathogens isolated from OE cases in dogs. In total, 57 dogs with clinical signs of OE were examined and bacteriologically tested. Hydrogels of Chitosan were synthesized by self-assembly and investigated. EO was extracted (Clevenger machine), and its ingredients were checked (GC-MS analysis) and encapsulated in chitosan-cholesterol nanoparticles. Disc-diffusion and broth Micro-dilution (MIC and MBC) examined its antimicrobial and therapeutic properties.
RESULTS
Staphylococcus pseudintermedius (49.3%) was the most common bacteria isolated from OE cases, followed by Pseudomonas aeruginosa (14.7%), Escherichia coli (13.3%), Streptococcus canis (9.3%), Corynebacterium auriscanis (6.7%), Klebsiella pneumoniae (2.7%), Proteus mirabilis (2.7%), and Bacillus cereus (1.3%). The investigation into the antimicrobial properties of Ajwain EO encapsulated in chitosan nanoparticles revealed that it exhibited a more pronounced antimicrobial effect against the pathogens responsible for OE.
CONCLUSIONS
Using chitosan nanoparticles encapsulated with EO presents an effective treatment approach for dogs with OE that conventional antimicrobial treatments have not cured. This approach not only enhances antibacterial effects but also reduces the required dosage of antimicrobials, potentially preventing the emergence of antimicrobial resistance.
Topics: Dogs; Animals; Oils, Volatile; Ammi; Chitosan; Otitis Externa; Microbial Sensitivity Tests; Anti-Bacterial Agents; Anti-Infective Agents; Bacteria; Escherichia coli; Cholesterol; Dog Diseases
PubMed: 38561827
DOI: 10.1186/s12917-024-03971-7 -
Nucleic Acids Research Apr 2024Genome-wide screens have become powerful tools for elucidating genotype-to-phenotype relationships in bacteria. Of the varying techniques to achieve knockout and...
Genome-wide screens have become powerful tools for elucidating genotype-to-phenotype relationships in bacteria. Of the varying techniques to achieve knockout and knockdown, CRISPR base editors are emerging as promising options. However, the limited number of available, efficient target sites hampers their use for high-throughput screening. Here, we make multiple advances to enable flexible base editing as part of high-throughput genetic screening in bacteria. We first co-opt the Streptococcus canis Cas9 that exhibits more flexible protospacer-adjacent motif recognition than the traditional Streptococcus pyogenes Cas9. We then expand beyond introducing premature stop codons by mutating start codons. Next, we derive guide design rules by applying machine learning to an essentiality screen conducted in Escherichia coli. Finally, we rescue poorly edited sites by combining base editing with Cas9-induced cleavage of unedited cells, thereby enriching for intended edits. The efficiency of this dual system was validated through a conditional essentiality screen based on growth in minimal media. Overall, expanding the scope of genome-wide knockout screens with base editors could further facilitate the investigation of new gene functions and interactions in bacteria.
Topics: Gene Editing; CRISPR-Cas Systems; Escherichia coli; High-Throughput Screening Assays; Genome, Bacterial; CRISPR-Associated Protein 9; Streptococcus; Streptococcus pyogenes; Machine Learning; RNA, Guide, CRISPR-Cas Systems
PubMed: 38499498
DOI: 10.1093/nar/gkae174 -
Frontiers in Veterinary Science 2023To investigate the antimicrobial effect of cold atmospheric plasma (CAP) on pathogens associated with canine bacterial keratitis.
PURPOSE
To investigate the antimicrobial effect of cold atmospheric plasma (CAP) on pathogens associated with canine bacterial keratitis.
MATERIALS AND METHODS
, , and strains, which were obtained from dogs with infectious keratitis, were subjected to testing. For each species, four isolates and a reference strain were cultivated on Columbia sheep blood agar and treated with the kiNPen Vet plasma pen from Neoplas GmbH, Greifswald, Germany. Various continuous treatment durations (0.5, 2, and 5 min) were applied, along with a 0.5-min treatment repeated four times at short intervals. These treatments were conducted at distances of 3 and 18 mm between the agar surface and the pen.
RESULTS
CAP treatment reduced bacterial growth in all three species. The most effective treatment duration was 5 min at 3 mm distance, resulting in inhibition zones ranging from 19 to 22 mm for , 26-45 mm for and an overall reduction of bacterial growth for . Inhibition zones were smaller with decreasing treatment duration and larger distance. Treatment times of 30 s repeated four times and 2 min showed comparable results. Treatment with argon alone did not lead to visible reduction of bacterial growth.
CONCLUSION
Argon cold atmospheric plasma demonstrated a potent antimicrobial effect on and strains with the latter showing the highest sensitivity.
PubMed: 38264471
DOI: 10.3389/fvets.2023.1320145 -
Journal of Veterinary Science Sep 2023Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) on the surface of , coded with gapC, is a glycolytic enzyme that was reported to be a moonlighting protein and virulence...
BACKGROUND
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) on the surface of , coded with gapC, is a glycolytic enzyme that was reported to be a moonlighting protein and virulence factor.
OBJECTIVE
This study assessed GAPDH as a potential immunization candidate protein to prevent streptococcus infections.
METHODS
Mice were vaccinated subcutaneously with recombinant GAPDH and challenged with . They were then evaluated using histological methods. rGAPDH of mouse bone marrow-derived dendritic cells (BMDCs) was evaluated using immunoblotting, reverse transcription quantitative polymerase chain reaction, and enzyme-linked immunosorbent assay methods.
RESULTS
Vaccination with rGAPDH improved the survival rates and decreased the bacterial burdens in the mammary glands compared to the control group. The mechanism by which rGAPDH vaccination protects against was investigated. experiments showed that rGAPDH boosted the generation of interleukin-10 and tumor necrosis factor-α. Treatment of BMDCs with TAK-242, a toll-like receptor 4 inhibitor, or C29, a toll-like receptor 2 inhibitor, reduced cytokines substantially, suggesting that rGAPDH may be a potential ligand for both TLR2 and TLR4. Subsequent investigations showed that rGAPDH may activate the phosphorylation of MAPKs and nuclear factor-κB.
CONCLUSIONS
GAPDH is a promising immunization candidate protein for targeting virulence and enhancing immune-mediated protection. Further investigations are warranted to understand the mechanisms underlying the activation of BMDCs by rGAPDH in a TLR2- and TLR4-dependent manner and the regulation of inflammatory cytokines contributing to mastitis pathogenesis.
Topics: Female; Animals; Mice; Toll-Like Receptor 4; Toll-Like Receptor 2; Streptococcus; Glyceraldehyde-3-Phosphate Dehydrogenases; Cytokines; Immunity, Innate; Immunologic Factors; Vaccines
PubMed: 38031651
DOI: 10.4142/jvs.23103