Hafize Tuğba Yüksel Dolgun

This pilot study characterised bacterial DNA profiles in 40 milk and 39 faecal samples from eight Kyrgyz mare–foal pairs collected at birth, 24 h, and days 7, 14, and 21 postpartum using V3–V4 16S rRNA gene sequencing. Permutation Friedman tests detected temporal differences in foal faecal Shannon diversity and observed feature counts (Holm-adjusted p = 0.020 for both), but not in milk. Faecal diversity was descriptively lower at 24 h and day 7 than at birth and increased at days 14–21. Animal-blocked weighted UniFrac PERMANOVA detected a temporal effect in faecal DNA profiles (Holm-adjusted p = 0.0028), but not in milk (p = 0.0956). Pair-blocked milk–faecal comparisons were significant at each time point (Holm-adjusted p = 0.0391), although differences in dispersion limit interpretation. Without sequenced negative controls, background contamination cannot be distinguished from genuine milk-associated bacterial DNA; therefore, milk profiles cannot be confidently attributed to resident milk microbiota. Observed taxonomic similarities do not demonstrate microbial transmission or milk-derived foal gut colonisation. Significance in faeces but not milk does not establish a difference between their temporal responses, which was not directly tested. These findings are exploratory and require controlled validation.

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.

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.

Streptococcus (S.) species are important pathogens that cause mastitis in?sheep. The study aimed to?examine Streptococcus species in?sheep milk with subclinical mastitis, assessing their prevalence, antimicrobial resistance, and virulence gene...