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This study aimed to investigate the prevalence and diversity of pathogenic bacteria associated with periodontal disease in Pit Bulls. This medium-large breed is frequently in close contact with humans. Dental plaque and subgingival swab samples were obtained from 90 dogs (40 males and 50 females) with periodontitis detected during routine veterinary clinic examinations in the Western Aegean region of Türkiye. Bacterial cells cultivated on agar plates were then subjected to PCR to amplify 16S rRNA genes, and 80 out of 90 samples (89%) were evaluated as positive. The positive samples were analysed for the presence of Porphyromonas gingivalis, Porphyromonas gulae, Treponema denticola, Tannerella forsythia, Capnocytophaga ochracea, Capnocytophaga sputigena, Prevotella intermedia, Prevotella nigrescens, Campylobacter rectus, Aggregatibacter actinomycetemcomitans and Eikenella corrodens. The most common species were P. gingivalis (98%), P. gulae and P. intermedia (60%). T. denticola (1.25%) and C. rectus (1.25%) were less commonly detected. It was observed that gender did not significantly affect the presence of bacteria. Notably, polymicrobial infections were present in 68% of positive cases, highlighting the complex microbial ecology of canine periodontitis. These findings highlight the clinical importance of periodontal pathogens in dogs and their potential zoonotic implications. The results emphasise the need for an integrated veterinary and medical approach to improve our understanding of the microbiological interactions between companion animals and humans, particularly systemic inflammatory and neurodegenerative disorders.

Objectives: Increasing antimicrobial resistance among foodborne pathogens, particularly extended-spectrum β-lactamase (ESBL) and plasmid-mediated AmpC β-lactamase (pAmpC) production, has become a major public health concern worldwide. This study aimed to determine the presence of Salmonella Enteritidis, Salmonella Typhimurium, and Escherichia coli O157:H7 in bovine carcasses and to evaluate their antibiotic resistance profiles together with ESBL and pAmpC resistance characteristics. Methods: A total of 300 bovine carcasses were examined for the presence of Salmonella spp. and E. coli O157:H7 using culture-based isolation methods following ISO 6579-1 and FDA guidelines, respectively. The isolates were confirmed by molecular methods, and stx1, stx2, eae, and hly were investigated in E. coli O157:H7 isolates. Antimicrobial susceptibility testing was performed according to EUCAST guidelines. ESBL and pAmpC production were determined phenotypically and subsequently characterized by molecular methods. Results: A total of 25 Salmonella spp. (32% S. Enteritidis and 68% S. Typhimurium) and 20 E. coli O157:H7 isolates were recovered from different bovine carcasses. stx2 was the most frequently detected virulence gene. Of the 31 phenotypically ESBL-positive isolates, 29 carried at least one ESBL-associated gene. The predominant ESBL gene was bla_CTX-M (79.3%), followed by bla_TEM and bla_SHV (37.9%). Among CTX-M gene groups, CTX-M-25 was the most prevalent (94.4%). Phenotypic pAmpC production was detected in 13 isolates, while 17 isolates carried at least one pAmpC-associated gene, with FOX identified as the predominant gene group. All isolates were resistant to pefloxacin, followed by gentamicin (93.3%) and cefoxitin (55.5%). Multidrug resistance was detected in 34 (75.6%) isolates. Conclusions: The detection of ESBL-producing, pAmpC-positive, and multidrug-resistant Salmonella spp. and Escherichia coli O157:H7 isolates in bovine carcasses indicates the presence of antimicrobial-resistant foodborne pathogens in the beef production chain. These findings highlight the need for continued monitoring of antimicrobial resistance and effective control measures at the slaughterhouse level.

Oral vaccine technologies offer significant advantages in veterinary applications by having the potential to simultaneously induce local and systemic immune responses in the gastrointestinal mucosa, going beyond traditional injection methods. Their low cost within the food production chain, elimination of needle use, and ability to immunize large animal populations en masse confer particular benefits under field conditions. Antigens transported to the gut‐associated lymphoid tissue via M cells trigger secretory IgA and systemic IgG production, thereby reinforcing mucosal barrier integrity and promoting the formation of immunological memory. This review will examine the fundamental characteristics of oral vaccines used in veterinary medicine, their immune mechanisms, and the factors influencing these mechanisms. Oral and injectable vaccines will be compared to elucidate their advantages and disadvantages. Additionally, strategies for the design and distribution of oral vaccines developed for animals and the challenges encountered throughout this process will be discussed. Finally, the current developments in this field will be reviewed.

In this study, a total of 400 samples were collected from the milk, skin, vaginal mucosa, and nasal mucosa of 50 lactating Hair goats and 50 lactating Saanen goats raised in the Aydın province during the summer of 2010. The samples were transported to the laboratory of the Department of Microbiology, Faculty of Veterinary Medicine, Adnan Menderes University. Staphylococcus aureus was isolated from 48 samples (12%). Polymerase chain reaction (PCR) analysis revealed that 13 (27%) of these isolates harbored the sek staphylococcal enterotoxin gene (278-bp fragment). Among the detected enterotoxin genes, 10 (66.7%) were obtained from milk isolates, 2 (22%) from nasal isolates, and 1 (11.1%) from a skin isolate. Distribution by breed showed that 8 (42.1%) of the genes were detected in milk isolates of Hair goats, 2 (25%) in milk isolates of Saanen goats, 1 (5.2%) in a skin isolate of a Hair goat, and 2 (10.5%) in nasal isolates of Hair goats. The higher prevalence of S. aureus in Hair goats may be associated with their extensive breeding practices and increased environmental exposure to the pathogen. These findings emphasize the importance of management, nutrition, and hygiene practices in Hair goat flocks. Furthermore, molecular methods provided rapid and highly sensitive detection of staphylococcal enterotoxin genes.

Blackleg, caused by Clostridium chauvoei, remains a serious disease of cattle and small ruminants. Potency testing of C. chauvoei vaccines is still based on guinea pig challenge assays, which in this study involved 300 Wistar Albino guinea pigs (350–450 g). Although regarded as the reference method, it is labor-intensive, time-consuming, and raises animal welfare concerns. This study aimed to evaluate whether an antigen-based ELISA could serve as a rapid, reproducible, and animal-friendly in vitro alternative for potency testing of inactivated C. chauvoei vaccines. Twenty commercial vaccines (15 with C. chauvoei antigen, 5 without) were evaluated by both the guinea pig challenge test and a flagellar antigen–specific ELISA. For each vaccine, 10 guinea pigs were vaccinated and 5 remained as controls. Relative potency (RP) was calculated against a standardized reference vaccine. Correlation between methods, sensitivity, and specificity were determined. The ELISA achieved 93.3% sensitivity, 100% specificity, and 95.0% relative accuracy. RP values of positive vaccines ranged from 1.02 to 5.44, showing a strong correlation with in vivo results (r = 0.882, p < 0.001). Intra-plate (CV < 10%) and inter-plate (CV < 15%) variation were within acceptable limits. No false positives occurred, and vaccines lacking C. chauvoei antigen produced very low RP values. The developed ELISA represents a reliable alternative to animal testing, significantly reducing both animal use and testing duration while maintaining accuracy. Implementation would align with 3R principles (Replacement, Reduction, Refinement) and enhance the efficiency of vaccine quality control protocols.

Dermatofitozis (Favus), Microsporum gallinae, Trichophyton simii ve Microsporum gypseum tarafından oluşturulan, kanatlılarda görülen bir mantar enfeksiyonudur. Dermatofitozis, derinin tüysüz bölgelerinde görülen beyazımsı, kabuklu lezyonlar ile karakterizedir ve doğrudan temas veya kontamine fomitler (örneğin, ahşap kümes yüzeyleri, tüy döküntüleri, yemlikler) yoluyla bulaşmaktadır. Hastalık genellikle sakal, ibik ve bacaklarda kabuklu lezyonlar, tüy dökülmesi ve deri kalınlaşması ile karakterizedir. Dermatofitozis etkenleri, keratinize dokuları istila eder ve zamanla kaba, pullu, petek benzeri kabukların oluşmasına neden olurlar. Tanı için mikroskobik inceleme, kültür ve moleküler yöntemler kullanılmaktadır. Tedavide topikal ve sistemik antifungal ajanlar uygulanırken, biyogüvenlik önlemleri ve kümes dezenfeksiyonu hastalığın yayılımını kontrol altına almak için önemlidir. Dermatofitozis zoonotik potansiyele sahip olmasına rağmen, insanlara bulaşması genellikle nadir ve sınırlı düzeydedir. Hijyen kurallarına uyulması ve enfekte hayvanlarla temastan kaçınılması, zoonotik bulaşı önlemek için gereklidir.

In this study, the presence of Candida species was investigated in 60 oral swab samples collected from dogs. The samples were cultured on Candida chromogenic agar and incubated at 30°C for 48 hours. Following the incubation period, growth was observed on 30 (50%) of the plates, resulting in the isolation of 57 Candida colonies. These colonies exhibited growth either as single or multiple agents on the chromogenic agar. Species identification was performed based on the color patterns displayed on the chromogenic agar, leading to the detection of six distinct Candida species. Among the isolates, 16 (28.1%) were identified as Candida krusei, 10 (17.5%) as Candida glabrata, 10 (17.5%) as Candida parapsilosis, 9 (15.8%) as Candida utilis, 7 (12.3%) as Candida tropicalis, and 5 (8.8%) as Candida albicans. To confirm their identification at the molecular level, all isolates were verified as belonging to the Candida genus using PCR with ITS3-ITS4 primers. The antifungal susceptibility of the isolates (n=57) was assessed using the disk diffusion method. The results revealed that the isolates exhibited resistance to miconazole (43.8%), ketoconazole (26.3%), flucytosine (100%), and fluconazole (93.1%), while showing high sensitivity to nystatin (93.1%). This study highlights the presence of pathogenic Candida species in the oral flora of dogs and underscores the emergence of antifungal resistance among these isolates. The findings suggest that the presence of Candida species in the oral microbiota of dogs could pose a potential health risk to both animals and humans, particularly in immunocompromised individuals.

This study was conducted to isolate Vibrio species from sea bass, identify them using molecular methods, and determine their antibiotic resistance. In the research, 100 sea bass samples taken from fish farms in the Aegean region between May and September 2021 were examined. After the phenotypic and genotypic identification of the isolates obtained from the samples, antibiotic resistances were determined by the disk diffusion method and antibiotic resistance genes were determined by multiplex PCR. In this study, 46 (46%) Vibrio spp. isolates were obtained from 100 sea bass samples by conventional and biochemical methods. The obtained 46 isolates were confirmed to be Vibrio spp. by 16S rRNA PCR. From 46 isolates, 22 (47,8%) isolates were identified as V. alginolyticus, 13 (28,2%) isolates as V. harveyi, 3 (6,5%) isolates as V. parahaemolyticus, 1 (2%) isolate as V. vulnificus and 7 (15%) isolates as Vibrio spp. by multiplex PCR. The highest resistance was found to ampicillin (84,8%) in the isolates in the antibiogram. All isolates were found to be susceptible to enrofloxacin and sulfamethoxazole-trimethoprim (100%). In isolates, the highest resistance gene was found to be trimethoprim resistance gene (63%), and the lowest resistance gene was found to be fluoroquinolone resistance gene (6,5%). In this study, it was determined that Vibrio species have an important role as a primary agent in fish diseases, molecular methods give more reliable results in identification, and there is single and multiple antibiotic resistance among isolates.

This study aimed to investigate the formation of antimicrobial resistance genes associated with vancomycin and gentamicin, as well as the capacity to develop biofilms, in Enterococcus sp. strains isolated from subclinical mastitis in sheep. In total, Enterococcus faecalis (22/26, 84.62%) was found to be the most prevalent species among the samples of mastitic milk collected from sheep. In general, E. faecalis strains exhibited higher resistance compared to Enterococcus faecium. After isolation and identification using polymerase chain reaction, a total of twenty-six enterococci (22 E. faecalis, 4 E. faecium) were submitted to susceptibility tests against eight antimicrobial agents. The isolates indicated multidrug resistance to amoxicillin-clavulanic acid (100%), kanamycin (100%), and trimethoprim-sulfamethoxazole (100%). All isolates were susceptible to ampicillin (100%), and florfenicol (100%) and vancomycin susceptibility was observed in 53.85% of the isolates. The dominant antimicrobial resistance genes detected in our isolates were vanB (19.23%), aph(2”)-Ia1 (61.54%), aph(2”)-Id1 (26.92%), and esp (65.38%) as the most common virulence gene. This research indicated a significant occurrence of antimicrobial resistance in E. faecalis and E. faecium strains obtained from subclinical sheep mastitis. The increasing resistance of enterococci to antibiotics poses a growing challenge to both human well-being and the environment.