Consolidated studies on animal, human, and environmental health have become very important for understanding emerging zoonotic diseases and the spread of antimicrobial resistance (AMR). The aim of this study was to analyse the oral microbiomes of healthy dogs and their owners, including determinants of AMR. Shotgun metagenomic sequencing detected 299 bacterial species in pets and their owners, from which 70 species were carried by dogs and 229 species by humans. Results demonstrated a unique microbial composition of dogs and their owners. At an order level, Bacteroidales were the most prevalent oral microbiota of dogs with significantly lower prevalence in their owners where Actinomycetales and Lactobacillales predominated. Porphyromonas and Corynebacterium were the most prevalent genera in dogs, whereas Streptococcus and Actinomyces were in animal owners. The resistances to macrolides, tetracyclines, lincosamides and Cfx family A class broad-spectrum β-lactamase were detected in both animal and human microbiomes. Resistance determinants to amphenicols, aminoglycosides, sulphonamides, and quaternary ammonium compounds were detected exceptionally in dogs. In conclusion, the study demonstrated different bacterial composition in oral microbiomes of healthy dogs without clinical signs of periodontal disease and their owners. Due to the low numbers of the samples tested, further investigations with an increased number of samples should be performed.

The bovine uterus, once considered sterile, is now recognized as a dynamic microbial ecosystem that undergoes substantial changes during the postpartum period and plays a critical role in reproductive health. This study investigated the composition and temporal dynamics of the uterine bacterial and fungal microbiota in postpartum Angus cows and showed that dietary grape pomace bolus supplementation was associated with temporal shifts in microbial community composition, including changes in selected bacterial taxa and increased fungal community stability. A total of 19 cows were allocated to control (n = 10) or treatment groups (n = 9), with treated animals receiving slow-release grape pomace boluses administered every three weeks from 21 days prepartum until 60–70 days postpartum. Uterine lavage samples were collected during the first (days 4–12) and ninth (days 63–70) postpartum weeks and analyzed using amplicon-based sequencing targeting the bacterial 16S rRNA (V3–V4) region and the fungal ITS2 region. The uterine microbiota exhibited pronounced temporal changes, with Firmicutes predominating in the early postpartum period and an increased abundance of potentially pathogenic Fusobacteria and Bacteroidetes observed by week nine postpartum, particularly in control cows. Grape pomace supplementation was associated with a more favorable bacterial profile, including a reduced relative abundance of key uterine pathogens such as Fusobacterium necrophorum and Trueperella pyogenes. The uterine mycobiome was dominated by Ascomycota across all groups; however, supplemented cows showed greater fungal community stability and a lower prevalence of opportunistic genera, including Candida spp. In conclusion, dietary grape pomace supplementation may beneficially modulate both bacterial and fungal uterine microbiota during the postpartum period, suggesting its potential as a natural strategy to support uterine microbial homeostasis and reproductive health in beef cows.

Periodontitis is a serious gum infection that damages the soft tissue and destroys the bone supporting the teeth. The aim of the study was to investigate the microbiota using traditional microbiology plating and metagenomic sequencing of extracted tooth alveoli in dogs with severe periodontitis. Isolation of culturable microorganisms was performed as part of bacteriological testing to provide bacteriological diagnosis to veterinary surgeons. Metagenomic sequencing was performed using shotgun sequencing on the Illumina HiSeq system platform. The most prevalent species at sites of periodontal infection detected by metagenomic sequencing were Porphyromonas gulae, Prevotella spp., Tannerella forsythia, Porphyromonas crevioricanis, Porphyromonas cangingivalis, and Bacteroides heparinolyticus. Pasteurella, Streptococcus, and Neisseria were the most frequently isolated culturable bacteria from infected sites detected by traditional microbiologic methods. Metagenomic data revealed that these three genera accounted for only 1.6% of all microbiota at the sites of infection. Antimicrobial resistance patterns of the isolated bacteria included resistance to ampicillin, doxycycline, sulfamethoxazole-trimethoprim, ciprofloxacin, colistin, cefotaxime, and chloramphenicol. Antimicrobial-resistant genes detected using shotgun sequencing also showed resistance to aminoglycosides and macrolides. Dogs with periodontal infections carry bacteria that can cause bite infections in humans as well as multi-resistant isolates. Therefore, treatment and prophylaxis or periodontal disease of dogs is important from a One Health perspective.

Canine periodontitis is one of the most prevalent chronic diseases for dogs over two years of age. Periodontal pockets may serve as a reservoir for opportunistic bacteria including Pasteurella stomatis, Neisseria animaloris, and Streptococcus canis; however, data on their antimicrobial susceptibility and potential One Health relevance remain limited. This pilot study investigated culturable bacterial isolates recovered from periodontal pockets of dogs with different stages of periodontal disease. Subgingival samples were collected under general anesthesia after periodontal probing and dental radiographic assessment during routine comprehensive oral health assessment and treatment (COHAT) procedures. Bacterial isolates were cultured, identified using MALDI-TOF MS, and tested for minimum inhibitory concentrations (MIC) against amoxicillin (AML), doxycycline (DX), trimethoprim–sulfamethoxazole (SXT), gentamicin (CN), chloramphenicol (C), and ciprofloxacin (CIP). In total, 122 isolates from 101 dogs were analyzed, including Pasteurella stomatis (n = 54), Neisseria animaloris (n = 33), and Streptococcus canis (n = 35). MIC distributions varied between bacterial species and antimicrobial agents, while interpretation was limited by the lack of species-specific veterinary medicine breakpoints for some isolates. These preliminary findings highlight the need for larger standardized studies to support antimicrobial resistance surveillance in canine oral microbiota.