Search Results (1,009)

Pasteurellosis is a major bacterial disease of domestic rabbits, commonly associated with respiratory disorders, abscesses, reproductive pathology, and systemic infections. This study investigated the occurrence, clinical manifestations, pathological lesions, and antimicrobial susceptibility of bacterial isolates obtained from rabbits raised in traditional extensive systems in western Romania, with identification of Pasteurella multocida performed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). A total of 308 rabbits from 23 holdings were clinically examined, necropsied when applicable, and subjected to bacteriological analysis. Clinical signs compatible with pasteurellosis were observed in 132 rabbits (42.9%), including respiratory diseases, abscess formation, otitis, and reproductive disorders. Samples collected from affected and deceased rabbits were cultured and analyzed using MALDI-TOF MS, confirming 87 isolates as P. multocida. Antimicrobial susceptibility testing using the VITEK 2 system revealed high resistance to tetracyclines (63.22%) and beta-lactams (55.17%), while higher susceptibility was observed for enrofloxacin (91.95%), gentamicin (89.66%), ciprofloxacin (86.21%), and florfenicol (80.46%). The presence of multidrug-resistant isolates highlights the need for laboratory-guided antimicrobial therapy and improved biosecurity measures in traditional rabbit holdings. Full article

Schistosomiasis, a neglected tropical disease (NTD), affects humans and leads to considerable clinical morbidity and severe long-term sequelae. Laboratory diagnostics for Schistosoma mansoni are mainly based on microscopic identification of eggs in stool, but sensitivity varies with infection intensity. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) is the gold standard for bacterial identification in high-income countries. Here, we first evaluate the capacity of MALDI-TOF MS and our existing ‘in-house helminths’ database for the identification of S. mansoni worms and eggs. A subset of adult worms and egg samples was used to generate MALDI reference spectra, which were added to the database and evaluated by blind-test identification. Subsequently, egg-free human stool was spiked with purified S. mansoni eggs and analyzed by MALDI-TOF MS. Log score values (LSVs) were employed to assess the reliability of identification. A total of 62/90 (68.9%, 95% confidence interval (CI): 58.3–78.2%) adult samples were correctly identified. After database expansion, 90/90 (100%, 95% CI: 96.0–100%) and 59/60 (98.3%, 95% CI: 91.1–100%) were correctly identified for adult worms and purified eggs, respectively. In contrast, the analysis of 35 human stool samples spiked with S. mansoni as eggs did not yield identifiable spectra. MALDI-TOF MS can be applied for the identification of isolated adult S. mansoni worms and eggs. Further investigations and optimization are necessary before potential application to clinical samples (e.g., for egg detection in stool). Full article

The occurrence of the European brown hare (Lepus europaeus Pallas 1778) has declined throughout Europe in recent years. However, it remains economically valuable as an important game species. To date, information on the individual microbiota of the European hare has been limited. The phylum Firmicutes (Bacillota) was dominant, and enterococci belong to this phylum. However, they can carry virulence factor genes. Therefore, this study aimed to address two aspects: the health of hares due to their recent decline, and, as a game animal, the protection of consumers’ health. Based on MALDI-TOF mass spectrometry, five strains were identified as Enterococcus faecium and two as E. faecalis; these findings were confirmed by genotyping using PCR and phenotypic analysis. The average value of lactic acid production was 0.680 ± 0.005 mmol/L. The strains lacked the virulence factor genes esp, agg, and gelE. However, they showed susceptibility to antibiotics and to postbiotic substances, even to 13 of 14 tested. PS/Ent M appears to be the most active PS against tested strains, with inhibitory activity of 25,600 AU/mL. Postbiotic substances represent a new tool for preventing unwanted microbiota in game animals. Full article

Background/Objectives: Pet birds are increasingly recognized as potential reservoirs of zoonotic and antimicrobial-resistant bacteria, raising concerns within the One Health framework. However, data on bacterial diversity and resistance profiles in clinically affected ornamental birds remain limited. Methods: This study, conducted over three years (November 2022–March 2026), included 198 pet birds presenting with digestive and respiratory disorders. From these birds, clinical samples were analyzed bacteriologically; resulting isolates were identified by MALDI-TOF mass spectrometry, and antimicrobial susceptibility assessed using the Kirby-Bauer disk diffusion method according to EUCAST and CLSI guidelines. Results: Bacterial growth was detected in 87.9% of cases, yielding 249 distinct isolates. Gram-positive cocci predominated (62.3%), led by Staphylococcus spp. (33.3%) and Enterococcus spp. (9.6%), while Escherichia coli (9.2%) was the primary Gram-negative species. At the genus level, Staphylococcus spp. demonstrated high susceptibility to amikacin (88.5%) but significant resistance to gentamicin (75.6%) and oxytetracycline (63.6%). In contrast, Escherichia spp. isolates were largely resistant, showing only 50% susceptibility to enrofloxacin and 40% to doxycycline, with resistance to tylosin reaching 90%. Overall, 57% of isolates were multidrug-resistant, with Staphylococcus spp. contributing most to this burden. Conclusions: These findings characterize clinically ill pet birds as significant carriers of multidrug-resistant bacteria, highlighting the need for routine diagnostics and improved antimicrobial stewardship in avian medicine. Full article

Staphylococcus aureus is a common opportunistic pathogen in rabbits and may cause localized or systemic infections that affect animal health and farm productivity. The present study aimed to investigate the clinical evolution, pathological lesions, and antimicrobial susceptibility profile of S. aureus infections in rabbits raised under traditional extensive systems in Western Romania. A total of 251 rabbits from 11 holdings located in Arad, Timiș, and Caraș-Severin counties were evaluated through epidemiological investigation, clinical examination, necropsy, and bacteriological analysis. Samples were cultured on Brain Heart Infusion medium and 5% sheep blood agar, and isolates were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Antimicrobial susceptibility testing was performed using an automated system (VITEK 2, bioMérieux) and interpreted according to EUCAST guidelines. Among the examined animals, 68 rabbits (27.1%) showed clinical lesions compatible with S. aureus infection. The most common manifestations included subcutaneous abscesses, otitis externa, rhinitis, mammary abscesses, pyometra, and dental abscesses. Necropsy revealed suppurative and septicemic lesions affecting multiple organs. Antimicrobial susceptibility testing indicated high resistance to penicillin (100%), tetracycline (76.5%), doxycycline (67.6%), and amoxicillin (63.2%). In contrast, florfenicol (69.1% susceptible), ciprofloxacin (61.8%), gentamicin (54.4%), and enrofloxacin (52.9%) showed better antimicrobial activity. The results confirm the clinical and microbiological relevance of S. aureus infections in rabbits raised under traditional conditions and highlight the need for improved biosecurity measures and rational antimicrobial use. Full article

Bacteria associated with unhatched sea turtle eggs remain poorly characterized at the genomic level. This study provides genome-scale characterization of bacterial isolates recovered from unhatched green sea turtle (Chelonia mydas) eggs at Akyatan Beach—a critical nesting site in the Eastern Mediterranean. Sampling 30 nests during the nesting season, we isolated bacteria from infected eggshells and dead embryos. Following Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry(MALDI-TOF MS) identification and 16S rRNA validation, we performed whole-genome sequencing (WGS) on Citrobacter farmeri and Enterobacter cloacae, two opportunistic pathogens of significant clinical and ecological concern. High-quality draft genomes revealed remarkable metabolic versatility, particularly within carbon and nitrogen pathways. Most notably, we identified extensive resistomes including resistance to $\beta$-lactams, fluoroquinolones, and aminoglycosides, alongside virulence factors for adhesion and iron acquisition. ANI analysis confirmed high genomic similarity to clinical reference strains, comparative genomic analysis revealed a substantial accessory gene pool, suggesting potential genomic flexibility between the two isolates. These findings provide the first genome-scale insight into these pathogens in C. mydas nests, and highlighting their genomic potential for opportunistic pathogenicity. Our results advocate for integrating genomic microbial surveillance into nesting beach management through a ‘One Health’ lens. Full article

Lactic acid bacteria are important components of the early gut microbiota in piglets and may contribute to gastrointestinal stability and control of enteric pathogens, particularly under increasing restrictions on antibiotic use in livestock production. This study aimed to perform in vitro phenotypic screening and characterization of lactic acid bacteria isolated from feces of suckling piglets aged 7–28 days. A total of 42 fecal samples were collected and cultured on selective media, yielding 318 colonies, of which 135 Gram-positive, rod-shaped, catalase-negative isolates were selected for further evaluation. These isolates were assessed for tolerance to acidic conditions (pH 2.0–3.1), bile salts (0.3–0.5%), cell surface hydrophobicity, hemolytic activity, and antibacterial activity against Escherichia coli and Staphylococcus aureus. Among the tested isolates, only two (PMvet212 and PMvet318) demonstrated limited tolerance to acidic and bile conditions and exhibited moderate antibacterial activity, with inhibition zones of approximately 10–12 mm. Identification using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry indicated that PMvet212 was closely related to Lactobacillus brevis, whereas PMvet318 was identified at the genus level as Lactobacillus sp. However, both isolates exhibited α-hemolytic activity and therefore did not meet the safety criteria required for probiotic application. In conclusion, although piglet-derived lactic acid bacteria may exhibit certain functional properties, the present findings highlight that probiotic potential is strain-specific and that rigorous multi-step screening, together with further in vivo validation, is essential before practical application can be considered. Full article

Protein profiling generated by MALDI-TOF (matrix-assisted laser desorption ionization-time-of-flight) was used to distinguish meat from different livestock species and identify meat species. Meat proteins from fresh beef (n = 12), pork (n = 7), chicken (n = 5) and tilapia fish (n = 3) were extracted and analyzed in a MALDI Biotyper mass spectrometer (Bruker Daltonics, Bremen, Germany) with alpha-cyano-4-hydroxycinnamic acid as the matrix. Mass spectra allowed the distinction of meat species, including between Nellore and Angus bovine breeds, and PCA classification revealed possible biomarkers for meat types. Our results corroborate MALDI-TOF mass spectrometry as an interesting tool for meat identification, which is useful for quality control and the certification of meat products. Full article

Conventional and emerging extraction methods for recovering phenolic compounds (PCs) from Pinus radiata bark were investigated for their potential use in bio-composites and bio-based biomaterial applications. To optimize the recovery process, a Response Surface Methodology (RSM) based on a Box–Behnken design was used to evaluate the effects of extraction time (20–100 min), temperature (20–80 °C), and water or ethanol-water solvent concentrations with β-cyclodextrin (βCD) or NaOH (0.5–1.5% w/v CD/db). Polyphenolic profiles of the extracts were characterized using Fourier transform infrared spectroscopy (FTIR), LC-LTQ-Orbitrap-MS, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used to evaluate the thermal stability and degradation behavior of the powdered extracts. Antioxidant capacity (DPPH, FRAP, ABTS) and antibacterial activity against Escherichia coli and Staphylococcus aureus were assessed by spectrophotometric assays and the agar diffusion method, respectively. Highest extraction yields were obtained using alkaline extraction (14.32%) and ultrasound-assisted extraction (UAE) (13.86%), followed by ethanol extraction (12.74%). Minimum inhibitory concentration (MIC) for P-βCD was 0.04 mg/mL, and the minimum bactericidal concentration (MBC) was 0.32 mg/mL against S. aureus. These results suggest a strong inhibitory capacity at low concentrations and the potential incorporation of these extracts into bio-based antimicrobial biomaterials. Full article

Otitis externa in dogs is primarily caused by Malassezia pachydermatis. Treatment involves antifungal and antiseptic agents; however, resistance among causative organisms has been noted. Pomelo (Citrus maxima) is a source of bioactive compounds with antimicrobial activity. Its extract mainly includes essential oils, which are mostly applied for alternative treatment for M. pachydermatis. The study aimed to investigate the anti-M. pachydermatis effects of pomelo peel extracts and their potential use in topical solutions for canine infections. M. pachydermatis was isolated from dogs and confirmed with Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF/MS). Antifungal susceptibility of M. pachydermatis to itraconazole was evaluated. Phytochemicals of essential oil and crude extract from C. maxima peel were determined using Gas Chromatograph–Mass Spectrometry (GC-MS/MS). In addition, the antifungal activity of the extracts was assessed using an agar plate dilution assay. The essential oil was formulated into a prototypic topical solution, and its effects on M. pachydermatis were observed in vitro. The prevalence of M. pachydermatis was 42%, with 53% having yeast on both ear sides. The minimum inhibitory concentrations (MIC) of itraconazole, essential oil, and crude extract to M. pachydermatis were 0.03–0.25 µg/mL, 1.0% v/v, and >200 mg/mL, respectively. The prominent phytochemicals in peel extracts were meranzin hydrate and D-limonene, identified in the crude extract and essential oil, respectively. Moreover, a topical solution containing essential oils inhibited M. pachydermatis growth and showed destructive effects on the yeast cell wall at higher concentrations. The essential oil exhibits antifungal activity against M. pachydermatis, primarily due to the high concentration of D-limonene. The growth was inhibited completely at MIC, observed over a 5-day period. Furthermore, the prototypic topical solution demonstrated an anti-M. pachydermatis effect. These findings suggest potential veterinary applications for pomelo peel extract, though further studies are necessary to assess stability, mechanism of action, and industrial suitability. Full article

Background/Objectives: Antimicrobial resistance (AMR) is a global threat to human, animal, and environmental health. Among bacteria, E. coli is frequently used as a key indicator of AMR. Despite their genetic proximity to humans, studies on AMR in Non-Human Primates (NHPs) remain limited, particularly in semi-anthropized environments. This study aims to characterize the antibiotic resistance profiles and phylo-groups of E. coli isolated from NHPs and humans at a primatology center. Methods: A total of 143 stool samples were collected, including 125 from NHPs and 18 from humans. Isolates were cultured on Eosin Methylene Blue agar and then identified by MALDI-TOF mass spectrometry. Antibiotic susceptibility was assessed using the Kirby–Bauer disk diffusion method, with 30 antibiotics following CASFM-EUCAST recommendations. E. coli phylo-groups were characterized by quadruplex PCR according to the Clermont method, targeting the genes. Results: A total of 122 E. coli isolates (85.31%) were recovered, with comparable prevalence observed across NHPs and human staff. More than half of the isolates (55.74%) were resistant to at least one antibiotic tested, and 12.3% were classified as multi-drug resistant (MDR). Resistance rates of isolates in Mandrillus sphinx, Pan troglodytes, and humans were 50.6%, 57.7%, and 80.0%, respectively, with no significant statistical difference (p = 0.11). A single Extended-Spectrum Beta-Lactamase (ESBL) producing isolate was identified in the mandrill. Phylo-group analysis revealed the dominance of group A (50%), followed by groups B1, D, and C. Conclusions: Resistance profiles and phylo-group distribution among NHPs could suggest bacterial exchange and potential for cross-transmission of AMR within the shared environment. Full article

Ascosphaera apis is a fungal pathogen of honeybee larvae and the primary cause of chalkbrood disease, which weakens bee colonies, impairing their ability to function effectively and making them more susceptible to other pathogens and environmental stressors. This study aimed to develop and validate an in-house matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) spectral library for A. apis. A new MALDI-TOF MS library was constructed using reference Ascosphaera species and validated through whole-genome-based confirmation of 31 clinical isolates of A. apis. Three different protein extraction methods were tested and compared: liquid cultivation, formic acid–ethanol extraction and extended direct transfer. Our findings demonstrate that MALDI-TOF MS is a rapid and reliable tool for identifying A. apis under the tested laboratory conditions and within the analyzed strain set, with no misidentifications observed for the liquid cultivation and formic acid–ethanol extraction methods. The extended direct mycelium transfer method was slightly less effective but still showed a high sensitivity of 83.9%. This study provides a foundation for improving diagnostic approaches in the management of honeybee fungal diseases. Full article

Avian infective endocarditis is an uncommon but severe disease that is typically diagnosed postmortem because of nonspecific clinical signs and rapid progression. In the present study, five broiler chickens (n = 5) from a commercial flock were examined with septicemia and lesions suggestive of endocarditis. This study reports the first molecularly confirmed and characterized case of valvular endocarditis associated with multidrug-resistant Vagococcus fluvialis in poultry and provides a comprehensive review of bacterial endocarditis in avian species. The case involved a broiler chicken that presented with sudden death and septicemic lesions, including vegetative valvular endocarditis, pericarditis, and multiorgan involvement. Bacterial isolates recovered from cardiac lesions were identified as V. fluvialis using MALDI-TOF mass spectrometry and confirmed by 16S rRNA gene sequencing. Antimicrobial susceptibility testing revealed a multidrug resistance profile, with resistance to several antimicrobial classes commonly used in poultry production. The literature review identified published studies describing avian infective endocarditis, which predominantly affects poultry and is caused mainly by Gram-positive bacteria, with clinical signs and necropsy findings largely overlapping across etiologies. These findings highlight the novelty of V. fluvialis as a potential etiological agent of avian infective endocarditis and underscores the diagnostic challenges associated with avian endocarditis, particularly when uncommon pathogens are involved, and underscore the importance of advanced identification methods for an accurate etiological determination. Collectively, the results of this study expand the spectrum of bacterial species associated with avian infective endocarditis and emphasize the relevance of antimicrobial resistance and improved diagnostic strategies in poultry health and disease surveillance. Full article

Drought stress significantly constrains crop productivity and yield stability. Sorghum (Sorghum bicolor L. Moench), a C4 cereal widely cultivated in arid and semi-arid regions, exhibits high water-use efficiency and remarkable drought tolerance. Understanding both the impacts of drought and the plant’s response mechanisms is essential for enhancing drought resilience in this crop. In this study, physiological changes and differential protein accumulation were analyzed in leaves of the sorghum inbred line BT × 623 under 10% PEG-6000-induced drought stress. The physiological adaptation to drought was characterized by improved water retention and mitigation of oxidative damage through the synergistic action of antioxidant enzymes. Using two-dimensional electrophoresis (2-DE) and MALDI-TOF-TOF mass spectrometry, 43 protein spots were successfully identified, corresponding to 38 unique proteins differentially expressed under osmotic stress. These proteins function in diverse biological processes, including protein synthesis, processing, and degradation; photosynthesis; carbohydrate and energy metabolism; transcriptional regulation; stress and defense; lipid and membrane metabolism; and amino acid metabolism. Proteomic profiling revealed that the coordinated modulation of multiple functional groups, such as those involved in photosynthesis, energy metabolism, transcriptional adjustment, ROS scavenging, and protein turnover, underpins sorghum’s osmotic stress adaptation. These findings provide key insights into the drought resistance mechanisms of sorghum at both physiological and proteomic levels. Full article

Background/Objectives: Multidrug-resistant (MDR) Escherichia coli has increasingly been recognized as a pathogen capable of causing severe systemic infections in various animal species. However, reports describing respiratory and septicemic infections caused by MDR E. coli in guinea pigs remain scarce. The objective of this report was to describe the clinical, pathological, and microbiological findings associated with a fatal infection in a domestic guinea pig. Case Study: A 10-month-old female guinea pig (Cavia porcellus), kept as a companion animal in a household environment, presented with acute respiratory distress, lethargy, and anorexia, progressing rapidly to death within approximately 36 h of onset. Post-mortem examination revealed severe pulmonary congestion, diffuse inflammatory lesions in the trachea, and generalized vascular congestion in multiple organs. Bacteriological cultures obtained from lung and bone marrow samples yielded pure growth of Escherichia coli. Identification was confirmed using MALDI-TOF mass spectrometry. Antimicrobial susceptibility testing demonstrated resistance to several antibiotic classes, including β-lactams, fluoroquinolones, tetracyclines, sulfonamides, and phenicols, while susceptibility was retained only to aminoglycosides. Molecular analysis revealed the presence of virulence genes involved in adhesion and iron acquisition, supporting the pathogenic potential of the isolate. Conclusions: This report highlights the ability of MDR E. coli to cause severe respiratory and systemic infections in guinea pigs. The findings underline the importance of early diagnosis, appropriate antimicrobial stewardship, and improved husbandry conditions in preventing such infections. From a One Health perspective, the circulation of resistant strains in companion animals may represent a potential risk for both environmental and human health. Full article