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Phytochemical nanoemulsions, such as thymoquinone nanoemulsions (TQN), are regarded as innovative alternatives to antimicrobials that significantly improve the performance, digestion, antioxidant potential and immunity of rabbits. Thus, the potential effects of TQN on growth, digestibility, antioxidant potential, immunity and resistance against Pasteurella multocida (P. multocida) in rabbits were assessed. Herein, 240 rabbits were offered either a basal diet or diets fortified with three TQN-graded concentrations. At 60 days of age, rabbits were challenged with multidrug-resistant (MDR) virulent P. multocida strain. Our outcomes described that dietary inclusion of TQN, especially at higher concentrations, significantly enhanced the growth performance of rabbits, which was supported by increasing the levels of jejunal lipase, amylase and trypsin enzymes. Of note, the levels of muscle and jejunal antioxidant enzymes [superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT) and total antioxidant capacity (T-AOC)], serum immunological markers (IgG, IgG, IgM and total Igs) and blood phagocytic percentage were significantly provoked after TQN fortification; meanwhile, the levels of muscle and jejunal MDA, serum biochemical parameters (total cholesterol, TG and LDL), abdominal fat percentage, breast and thigh cholesterol were significantly decreased following TQN supplementations. Our findings showed that TQN protected rabbits against P. multocida experimental challenge as evidenced by reducing P. multocida counts in rabbits' lungs, downregulating the transcription levels of P. multocida virulence-related genes (ptfA, toxA and nanB) at 48 and 96 h post-infection and ameliorating the expression levels of cytokines-related genes (IL-1β, IL-10, IL-8, IL-6, DEFB1, TNF-α, TLR-4 and TLR-2) at 96 h post-infection. Our findings suggest the utilization of TQN in rabbits' diets due to their stimulating effects on digestibility as well as their growth-promoting, anti-inflammatory, antioxidant, antibacterial, anti-virulence and immunostimulant properties, which enhance the rabbits' P. multocida resistance. [ABSTRACT FROM AUTHOR]

Poultry bacterial pathogen is a major problem in poultry farms, with serious consequences for poultry and human. Two hundred samples of apparently health and freshly died broiler were collected from different commercial farms at Sharkia governorate, Egypt. Salmonella spp. detected in (29%) of examined specimens and serologically identified into S. Typhimurium, S. Kentucky, S. Infantis, S. Enteritidis and S. Agama with percentages 9.5%, 6.5%, 5%, 4.5% and 3.5%, respectively. Meanwhile, Pseudomonas spp. detected in (19%), the most prevalent serotype was P. aeruginosa O2, O5, O9, and O11. However, the antimicrobial-resistant strains of pathogens continuously emerge, with ineffective of medical treatments, thus, the isolates were examined for detection of multidrug resistant (MDR), doxycycline exhibited the highest antimicrobial activity against Salmonella spp. (55.17%); and ceftriaxone and doxycycline against Pseudomonas spp. (52.63%). Uniplex PCR examination for ampC, stn, tetA(B), Integrase genes on MGEs were detected in all Salmonella spp. isolates, and mexR, tetA (B), Integrase genes in all examined MDR P. aeruginosa isolates, meanwhile, exoU detected in 80% on MGES. A novel antibacterial strategy was achieved to minimize economic burdens and the health associated with antimicrobial resistance which obliterate pathogens without any adverse effects on poultry and human. Therefore, the application of a trial using M. Oleifera nanoemulsion in order to control the multidrug resistant genes expression. These findings demonstrated that M. Oleifera nanoemulsion was a good choice to its potential as a drug that can be used against Salmonella and P. aeruginosa in poultry industry. [ABSTRACT FROM AUTHOR]

Objective: This study was conducted to evaluate the effect of composting on the count of Salmonella spp., Clostridium perfringens, and New Castle virus (NDV) isolated from broilers' litter. Moreover, to verify the impact of compost thermal stress on the expression of thermal genes harbored in the isolated bacteria. Materials and Methods: The prevalence of enteric aerobic and anaerobic infections by Salmonella spp., C. perfringens, and viral infections by NDV were investigated in litter samples collected from 100 broiler flocks by conventional methods and polymerase chain reaction. Results: The samples were positive for Salmonella spp., C. perfringens, and NDV, with prevalence rates of 60%, 55%, and 30%, respectively. An experiment to study the effect of compost on the microbiological quality of litter was applied using five compost heaps with an initial average count of Salmonella typhimurium (3.2 x 105CFU CFU/gm), C. perfringens (6.4 x 105 CFU/gm), and an average titer NDV (105.5 embryo infectious dose50/gm). The microbiological count of heaps after 15 days of composting revealed a reduction in the count of S. typhimurium and C. perfringens by 4 log10 CFU/gm and 3 log10 CFU/gm, respectively. Moreover, the hemagglutinating test revealed no detection of NDV after 15 days of composting. A high degree of downregulation of expression of the thermal genes, dnaK in S. typhimurium isolates and cpe gene in C. perfringens isolates, was detected by quantitative reverse transcription PCR. Conclusion: The reduction of pathogen counts, the simplicity, and the low cost associated with composting for only 15 days advocate the recommendation for raising awareness of composting as a routine biosecurity measure to prevent the spreading of infection and promote its safe use in agribusiness. [ABSTRACT FROM AUTHOR]

Salmonellosis caused by virulent multidrug-resistant strains is a great concern of the poultry industry; thus, the prevalence, resistance genes profile, and development of customized vaccines were evaluated in poultry species. Thus, 100 cloacal swabs from pigeons, household chickens, and commercial broilers were collected from Sharkia governorate, Egypt; 31% were positive for Salmonella serovars confirmed by the invA gene. All isolates were examined for antimicrobial susceptibility for detecting antibiotic resistance genes on plasmid by PCR, which demonstrated qepA, mcr1, tetA(A), and floR genes (100%) for each, while sulI and aadA1 genes were 93.8% and 87.5%, respectively. A phylogenetic tree was constructed to illustrate the evolutionary relationships between different strains in Egypt. Additionally, a bivalent killed Salmonella vaccine comprising two isolated serovars of Salmonella enterica (S. Typhimurium and S. Enteritidis) was developed and evaluated for its efficacy in specific pathogen-free (SPF) chickens. Vaccinated chickens developed a high humeral response measured by ELISA. Moreover, the protection rate of the developed vaccine in the challenge test was 85%, with less fecal shedding. The findings suggest that customized vaccines prepared from local circulating strains can be used as an alternative effective control tool against salmonellosis. [ABSTRACT FROM AUTHOR]

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Shiga-toxin-producing Escherichia coli (STEC) are the most important recently emerged group of food-borne pathogens. Among fifty EHEC strains, thirty strains were found as non O157 EHEC (60%) by serotyping. Also the highest incidence of O26 and O111 were 16% and 14%, respectively, meanwhile the lowest was of O128 (2%). Antibiotic resistance profiles for these strains showed 100% resistance to: sulfamethoxazole, Trimethoprime, chlormphencal, colistin, gentamycin and tetracycline. However, they showed 85% resistance to streptomycin and doxycycline, 80% resistance to cefotraxone while their resistance for amoxicillin clavulanic acid was 75%. PCR examination for twenty strains of EHEC non O157 revealed stx1 gene in 45%, stx2 in 65% while hly in 80% of the examined strains. Antimicrobial resistance genes for these strains confirmed that sulI, aadA and blaTEM resistance genes were detected in percentages of 85%, 75% and 60%, respectively. Recommendation for minimizing an excessive use of antibiotics in the veterinary field and periodically use of different antibiotics could overcome the problem of increased bacterial resistance. [ABSTRACT FROM AUTHOR]

To date, there is limited data about the genetic relationship of Escherichia coli between wild birds and cattle because these birds act as silent vectors for many zoonotic bacteria. This study aimed to elucidate the role of rooming wild birds in the vicinity of cattle farm in transmission of the same pathogenic E. coli variants, identifying their virulence, resistance traits and genetic similarities of fimH virulence gene. About 240 faecal/cloacal swabs were collected from both species and examined bacteriologically. Escherichia coli was yielded in 45.8% and 32.5%, respectively, of examined cattle and wild birds. The most prevalent detected E. coli serovar was O26. High tetracycline and chloramphenicol resistance were recorded; however, gentamycin and ciprofloxacin exhibited the highest sensitivity rates. Polymerase chain reaction (PCR) conserved genotypic resistance (tetA and blaCTX-M) and virulence attributes (fimH, stx1, eaeA and ompA) of E. coli isolates were discussed in detail. The fimH gene revealed 100% sequence similarity when comparing with different E. coli isolates globally and locally. Finally, a close genetic association of E. coli with both wild birds and cattle was detected, thus strengthening its role in the dissemination of the infection via environment. Prevention and conservative policy should be carried as E. coli constitute enormous significant zoonotic risks to livestock and animal workers. Also, further studies to the whole genome sequencing of fimH, other virulence and resistance genes of E. coli are recommended trying to limit the possibilities of co-infection and transfer among different species.Contribution: The current study recorded updated data about the critical infectious role of wild birds to livestock, including cattle farms in Egypt. It also delivered some recommendations for good hygienic practices in cattle farms which must be implemented for handling animal manure.