Campylobacter jejuni is the leading cause of foodborne bacterial gastroenteritis in humans worldwide. Contaminated chickens and their products are the main sources of human campylobacteriosis. Therefore, this study aimed to detect the genotypic and virulence genes‘ profiles of multi-drug resistant (MDR) C. jejuni isolates and to assess the effects of sub-inhibitory concentrations (SICs) of eugenol and beta-resorcylic acid on the virulence of avian MDR C. jejuni isolates. These isolates were clustered together with the human isolates via enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) fingerprinting. A total of 345 samples were collected from human stool (100) and different chicken (245) samples in Sharkia Governorate, Egypt. Conventional phenotypic methods identified 113 isolates (32.8%) as C. jejuni, and all C. jejuni isolates were MDR and resistant to erythromycin and ampicillin. The genes virB11, wlaN, and flaA were detected in 52%, 36% and 100% strains, respectively. ERIC-PCR yielded 14 profiles and five main clusters. Interestingly, human and chicken C. jejuni isolates were clustered together in ERIC-PCR clusters II-V, which confirmed the genetic relatedness between the isolates from both origins. Beta-resorcylic acid and eugenol inhibited the invasion of C. jejuni isolates to chicken intestinal cells by 41.66–38.19% and 31.94–29.16%, respectively, and minimized the transcription of flaA, virB11, and wlaN genes in the tested isolates by real-time quantitative reverse transcription PCR (qRT-PCR). In essence, eugenol and beta-resorcylic acid are promising natural antimicrobials for minimizing the virulence of MDR C. jejuni in chickens, thereby managing human campylobacteriosis.

Plant-derived bioactive compounds with promising nutritional and therapeutic attributes (phytogenics) are among the top priorities in the aquaculture sector. Therefore, the impact of thymol (Thy) and/or thymoquinone (ThQ) on the growth, immune response antioxidant capacity, and Aeromonas sobria (A. sobria) resistance of Nile tilapia was investigated. Four fish groups were fed a control diet and three basal diets supplemented with 200 mg/kg diet of Thy or ThQ and a blend of both Thy and ThQ at a level of 200 mg/kg diet each. At the end of the feeding trial (12 weeks), the tilapias were challenged intraperitoneally with virulent A. sobria (2.5 × 108 CFU/mL) harboring aerolysin (aero) and hemolysin (hly) genes. The results revealed that tilapias fed diets fortified with a combination of Thy and ThQ displayed significantly enhanced growth rate and feed conversion ratio. Notably, the expression of the genes encoding digestive enzymes (pepsinogen, chymotrypsinogen, α-amylase and lipase) and muscle and intestinal antioxidant enzymes (glutathione peroxidase, catalase and superoxide dismutase) was significantly upregulated in Thy/ThQ-fed fish. An excessive inflammatory response was subsided more prominently in the group administrated Thy/ThQ as supported by the downregulation of il-β, il-6 and il-8 genes and in contrast, the upregulation of the anti-inflammatory il-10 gene. Remarkably, dietary inclusion of Thy/ThQ augmented the expression of autophagy-related genes, whilst it downregulated that of mtor gene improving the autophagy process. Furthermore, Thy/ThQ protective effect against A. sobria was evidenced via downregulating the expression of its aero and hly virulence genes with higher fish survival rates. Overall, the current study encouraged the inclusion of Thy/ThQ in fish diets to boost their growth rates, promote digestive and antioxidant genes expression, improve their immune responses and provide defense against A. sorbia infections with great economic benefits.

In recent times, resistant foodborne pathogens, especially of the Campylobacter species, have created several global crises. These crises have been compounded due to the evolution of multidrug-resistant (MDR) bacterial pathogens and the emergence of extensively drug-resistant (XDR) and pan-drug-resistant (PDR) strains. Therefore, this study aimed to investigate the development of resistance and the existence of both XDR and PDR among Campylobacter isolates. Moreover, we explored the use of the polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) technique for the detection of fluoroquinolone (FQ)-resistant Campylobacter isolates. A total of 120 Campylobacter isolates were identified depending on both phenotypic and genotypic methods. Of note, cefoxitin and imipenem were the most effective drugs against the investigated Campylobacter isolates. Interestingly, the majority of our isolates (75%) were MDR. Unfortunately, both XDR and PDR isolates were detected in our study with prevalence rates of 20.8% and 4.2%, respectively. All FQ-resistant isolates with ciprofloxacin minimum inhibitory concentrations ≥4 µg/mL were confirmed by the genetic detection of gyrA chromosomal mutation via substitution of threonine at position 86 to isoleucine (Thr-86-to-Ile) using the PCR-RFLP technique. Herein, PCR-RFLP was a more practical and less expensive method used for the detection of FQ resistant isolates. In conclusion, we introduced a fast genetic method for the identification of FQ-resistant isolates to avoid treatment failure through the proper description of antimicrobials.

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Campylobacter species (spp.) are one of the most important causes of human bacterial gastroenteritis in foods of animal origin. Recently, with the spread of multi-drug-resistant (MDR) and extensively drug-resistant (XDR) Campylobacter spp., natural alternative therapeutic methods are urgently required. Phytogenic active principles have gained considerable attention due to their proficiency to enhance gut health and, thereby, performance of broiler chickens. Thus, the current study aims to determine the prevalence and antimicrobial resistance of Campylobacter spp. of different chicken sources in Sharkia Governorate, Egypt, and to assess the growth-promoting, immunostimulant and antimicrobial effects of a mixture of eugenol and trans-cinnamaldehyde in an in vivo approach. A total of 101 (67.3%) campylobacter isolates was identified, according to both phenotypic and genotypic techniques. Moreover, all of the campylobacter isolates were resistant to erythromycin, trimethoprim/sulfamethoxazole, and ampicillin (100% each). Of note, a dietary supplementation of the mixture of eugenol and trans-cinnamaldehyde led to a significant improvement of the feed conversion ratio and body weight gain and a decrease in the cecal C. jejuni loads in the broilers challenged with XDR C. jejuni. Additionally, eugenol and the trans-cinnamaldehyde mixture had protective activities via the down-regulation of XDR C. jejuni (flaA, virB11 and wlaN) virulence genes and proinflammatory cytokines (TNF-α, IL-2, IL-6, and IL-8), and the up-regulation of anti-inflammatory cytokine IL-10. Thus, we recommend the usage of a mixture of eugenol and trans-cinnamaldehyde as an alternative to antimicrobials for the control and treatment of campylobacter infections.

2004 and García-Sánchez et al. 2018). In the early 1970s, a special filtration method was developed for identification of Campylobacter in veterinary medicine, which allowed Butzler to detect these Campylobacter, mainly Campylobacter jejuni is viewed as one of the most well-known reasons of foodborne bacterial diarrheal sickness in people around the globe. The genus Campylobacter contains 39 species (spp.) and 16 sub spp. Campylobacter is microaerophilic, Gram negative, spiral-shaped rod with characteristic cork screw motility. It is colonizing the digestive system of numerous wild and household animals and birds, particularly chickens. Intestinal colonization brings about transporter/carrier healthy animals. Consequently, the utilization of contaminated meat, especially chicken meat is the primary source of campylobacteriosis in humans and chickens are responsible for an expected 80% of human campylobacter infection. Interestingly, in contrast with the most recent published reviews that cover specific aspects of campylobacter/campylobacteriosis, this review targets the taxonomy, biological characteristics, identification and habitat of Campylobacter spp. Moreover, it discusses the pathogenesis, resistance to antimicrobial agents and public health significance of Campylobacter spp. Finally, it focuses on the phytochemicals as intervention strategies used to reduce Campylobacter spp.in poultry production. ARTICLE INFO

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Among many bovine Mycoplasma species (spp.), Mycoplasma bovis is recognized as a significant causative agent of respiratory diseases in cattle. In recent years, resistant M. bovis isolates, especially to fluoroquinolones, have been reported globally as a result of the extensive usage of antimicrobials in the treatment of bovine pneumonia. Therefore, the aim of this study is to investigate the prevalence and antimicrobial susceptibility patterns of bovine Mycoplasma spp. isolated from the respiratory tracts of cattle in Egypt and to assess the fluoroquinolones resistance in the recovered mycoplasma isolates via broth microdilution and conventional PCR techniques. Conventional phenotypic methods identified 128 mycoplasma isolates (32%) from 400 different samples, with M. bovis being the predominant spp. (61%), followed by M. bovirhinis (15%). Of note, mycoplasma isolates were rarely isolated from total healthy lung tissues (7/55, 12.7%), but they were frequently isolated from pneumonic lungs (31/45, 68.9%). All the examined mycoplasma isolates (n = 76) were sensitive to tilmicosin, tylosin, tulathromycin, spiramycin, and spectinomycin (100% each), while 60.5% and 43.4% of the examined isolates had high minimum inhibitory concentration (MIC) values to enrofloxacin and doxycycline, respectively. Three and two mycoplasma isolates with high enrofloxacin MICs were confirmed to be M. bovis and M. bovirhinis, respectively, by PCR assays. All molecularly confirmed mycoplasma isolates (n = 5) were positive for the gyrA gene (100%); meanwhile, three isolates (60%) were positive for the parC gene. In conclusion, our findings revealed alarming resistance to enrofloxacin and doxycycline antibiotics; thus, antimicrobial usage must be restricted and molecular techniques can help in the rapid detection of the resistant strains.