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This study explores the potential of electrospun polyvinyl alcohol (PVA) incorporating Eucalyptus camaldurensis extract (ELE) as an innovative wound dressing strategy to address the escalating threat of antibiotic resistance and associated complications in bacterial infections of wounds. The investigation is grounded in the recognition of the antibacterial properties inherent in medicinal plants and the advantageous release characteristics of nanomaterials, particularly electrospun nanofibers that closely mimic the extracellular matrix. Utilizing the electrospinning technique, nanofiber mats were fabricated with hydroalcoholic Eucalyptus camaldulensis extract, and their structural and morphological attributes were comprehensively characterized using scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD). The study employed 60 male Wistar rats, categorizing them into groups treated with PVA/ELE, nitrofurazone, normal saline, and PVA wound dressings. Microbial and histopathological analyses were conducted at specified intervals postinfection. The results unveiled the remarkable antibacterial efficacy of PVA/ELE, as evidenced by a substantial reduction in bacterial count compared to control groups. Furthermore, the PVA/ELE group demonstrated superior wound size reduction, reepithelization, and collagen deposition, akin to the effects observed in the nitrofurazone group. The findings suggest that PVA/ELE exhibits significant antimicrobial potential and promotes advanced wound-healing processes. Consequently, this electrospun nanofiber formulation, enriched with ELE, emerges as a promising and viable alternative for conventional wound care, offering multifaceted benefits in combating bacterial infections and facilitating wound healing. [ABSTRACT FROM AUTHOR]

Background and Objectives: Antibiotic resistance within the poultry sector presents a considerable health concern due to treatment inefficacy and resistance transmission to humans and the environment. The investigation of plasmid-mediated quinolone resistance (PMQR) in Escherichia coli, acknowledged for its role in advancing resistance, remains inadequately studied in Iranian poultry. This study aimed to evaluate PMQR gene prevalence as well as to determine correlation between resistance phenotype and genotype in E. coli obtained from poultry colibacillosis. Materials and Methods: A collection of 100 E. coli isolates from the viscera of broilers suspected to colibacillosis was assessed. Using the Kirby-Bauer disk diffusion method, antimicrobial susceptibility tests were conducted for ofloxacin, nalidixic acid, levofloxacin, ciprofloxacin, and ampicillin. Additionally, PCR was employed to screen for qnrS, qnrB, and aac(6)Ib-cr genes. Results: Among the analyzed E. coli isolates, 51% demonstrated resistance to at least one of the tested antibiotics, with 17% exhibiting resistance to four different antibiotics. Nalidixic acid displayed the highest resistance rate at 48%, while ampicillin had the lowest at 16%. PMQR genes were detected in 28% of the E. coli isolates, with aac(6')-Ib-cr being the most prevalent at 14%, followed by qnrB in 13%, and qnrS in 7%. Conclusion: The study underscores the vital need for careful antibiotic usage in poultry to curb the emergence of antibiotic-resistant bacteria. The results illuminate the prevalence of PMQR genes and their association with resistance trends in Iranian poultry, forming a pivotal basis for forthcoming approaches to combat antibiotic resistance within the poultry sector. [ABSTRACT FROM AUTHOR]

With increasing antibiotic resistance, control of wound infection using alternative compounds has been considered. Electrospun nanofibers have remarkable characteristics for tissue engineering due to their mainly morphological similarity to the natural extracellular matrix which makes them an ideal candidate for wound dressings. This study aimed to evaluate the antibacterial effects of pomegranate seed extract (PSE) incorporated electrospun polyvinyl alcohol (PVA) on staphylococcus aureus-infected surgical wounds. After preparing the hydroalcoholic pomegranate seed extract, electrospun PVA/PSE nanofibrous mats were fabricated using the electrospinning method. The morphological and structural properties of the fabricated mats were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). Microbial and histopathological assessments were performed on 60 male Wistar rats. The animals were divided into four groups, and the wounds in each group were covered with PVA/ PSE, nitrofurazone, normal saline, and PVA wound dressings. The dressings were changed once every two days. Microbial and histopathological assessments were carried out on days 7, 14, and 21 after the infection. The MIC of PSE was 16 mg/ml and the bacterial count on day 7 in the PVA/PSE and nitrofurazone group was significantly lower than the two groups of control and PVA nanofibers (P < 0.05). The groups treated with nitrofurazone and PVA/PSE showed better wound size reduction than the control groups and appropriate healing progression was observed in the groups of PVA/PSE and nitrofurazone. The results revealed that PVA/PSE possessed high antimicrobial potential and improved re-epithelization and collagen deposition as well as nitrofurazone in the course of treatment. Therefore, it may be considered a promising alternative for clinical administration. [ABSTRACT FROM AUTHOR]

Objectives: The emergence of colistin-resistant Enterobacteriaceae from human and animal sources is one of the major public health concerns as colistin is the last-resort antibiotic for treating infections caused by multidrug-resistant Gram-negative bacteria. We aimed to determine the prevalence of the prototype widespread colistin resistance genes (mcr-1 and mcr-2) among commensal and pathogenic Escherichia coli strains isolated from food-producing and companion animals in Iran. Results: A total of 607 E. coli isolates which were previously collected from different animal sources between 2008 and 2016 used to uncover the possible presence of plasmid-mediated colistin resistance genes (mcr-1 and mcr-2) by PCR. Overall, our results could not confirm the presence of any mcr-1 or mcr-2 positive E. coli among the studied isolates. It is concluded that despite the important role of food-producing animals in transferring the antibiotic resistance, they were not the main source for carriage of mcr-1 and mcr-2 in Iran until 2016. This study suggests that the other mcr variants (mcr-3 to mcr-9) might be responsible for conferring colistin resistance in animal isolates in Iran. The possible linkage between pig farming industry and high level of mcr carriage in some countries needs to be clarified in future prospective studies. [ABSTRACT FROM AUTHOR]

Background: The transmission of antibiotic resistance through the food chain is one of the major health challenges, worldwide. A combination of essential oils with synergistic or additive effects to enhance the antimicrobial activity, is an applied approach to improve food safety. Methods: In this study, 93 E. coli isolated from the viscera of broilers, suspected to colibacillosis, were examined for detection of ESBL by the combined disk method according to Clinical and Laboratory Standards Institute. CTX-M was detected by PCR. Antibacterial activity of cinnamon and oregano essential oils were studied against bla CTX-M harboring isolates by broth microdilution method and fractional inhibitory concentration index. Results: According to the results of this study, 32/93 (34.4%) of tested samples produced ESBL, and 10/32 (31.2%) harbored CTX-M. All the CTX-M producing E. coli investigated by broth microdilution assay, were sensitive to cinnamon and oregano essential oils in the range of 400 to 3200 and 800 up to 1600ppm, respectively. Fractional inhibitory concentration indices ranging from 0.5 to 1.5, suggested synergistic, and additive inhibitory effect of cinnamon and oregano essential oils. Conclusion: The results of this study indicated that bla CTX-M might be transmitted to humans through chicken meat. The combination of cinnamon and oregano can be suggested as a safe biopreservative which leads to growth inhibition of antibiotic resistant E. coli. However, further studies should concern the potential interaction between essential oils and food matrices. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the diagnostic evaluation of milk lactate dehydrogenase (mLDH) and alkaline phosphatase (mALP) activities by receiver operating characteristic (ROC) analysis curve in early lactation of ewes with subclinical mastitis (SCM) and determine the correlation between number of somatic cell count (SCC) and mLDH and mALP activities. A total of 196 udder half milk samples were collected within the first 6 weeks of lambing. The SCM was determined by positive milk bacterial culture and positive California mastitis test (CMT); SCC was determined by fossomatic method and enzyme activities were determined spectrophotometrically. The mLDH and mALP of SCM cases were positively correlated with SCC values. Values of mLDH, mALP and SCC were significantly higher in SCM than non-SCM udder halves. The optimum cut-off points of mLDH and mALP activities for SCM diagnosis were determined at 203.61 (U L-1) and 329.84 (U L-1), respectively. In conclusion, SCC has positive correlation with mALP and mLDH activities in SCM ewes and mLDH and mALP activities could be considered as reliable indicators for intramammary inflammation diagnosis. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the diagnostic evaluation of milk lactate dehydrogenase (mLDH) and alkaline phosphatase (mALP) activities by receiver operating characteristic (ROC) analysis curve in early lactation of ewes with subclinical mastitis (SCM) and determine the correlation between number of somatic cell count (SCC) and mLDH and mALP activities. A total of 196 udder half milk samples were collected within the first 6 weeks of lambing. The SCM was determined by positive milk bacterial culture and positive California mastitis test (CMT); SCC was determined by fossomatic method and enzyme activities were determined spectrophotometrically. The mLDH and mALP of SCM cases were positively correlated with SCC values. Values of mLDH, mALP and SCC were significantly higher in SCM than non-SCM udder halves. The optimum cut-off points of mLDH and mALP activities for SCM diagnosis were determined at 203.61 (U L-1) and 329.84 (U L-1), respectively. In conclusion, SCC has positive correlation with mALP and mLDH activities in SCM ewes and mLDH and mALP activities could be considered as reliable indicators for intramammary inflammation diagnosis. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the diagnostic evaluation of milk lactate dehydrogenase (mLDH) and alkaline phosphatase (mALP) activities by receiver operating characteristic (ROC) analysis curve in early lactation of ewes with subclinical mastitis (SCM) and determine the correlation between number of somatic cell count (SCC) and mLDH and mALP activities. A total of 196 udder half milk samples were collected within the first 6 weeks of lambing. The SCM was determined by positive milk bacterial culture and positive California mastitis test (CMT); SCC was determined by fossomatic method and enzyme activities were determined spectrophotometrically. The mLDH and mALP of SCM cases were positively correlated with SCC values. Values of mLDH, mALP and SCC were significantly higher in SCM than non-SCM udder halves. The optimum cut-off points of mLDH and mALP activities for SCM diagnosis were determined at 203.61 (U L-1) and 329.84 (U L-1), respectively. In conclusion, SCC has positive correlation with mALP and mLDH activities in SCM ewes and mLDH and mALP activities could be considered as reliable indicators for intramammary inflammation diagnosis. [ABSTRACT FROM AUTHOR]

Ovine anaplasmosis is caused by two intraerythrocytic Anaplasma species (Rickettsiales, Anaplasmataceae). Ticks are the most important vectors in anaplasmosis. The mortality of this disease is relatively low, but it has worldwide distribution. The disease is endemic in some areas because chronic infected animals and infected vectors can act as Anaplasma reservoirs. Despite the low mortality, the economic loss which is caused by the disease is relatively high. In this research, one sheep flock which had been involved with anaplasmosis was described. Peripheral blood samples were taken and stained by Giemsa. Cell changes in the stained blood films that had been caused by anaplasmosis and management measures to prevent the disease were discussed in details. This study is important because it was done in a naturally Anaplasma-infected flock, emphasized on valuable changes in the infected blood films, and discussed the importance of preventive measures in an area. [ABSTRACT FROM AUTHOR]

The wound infection is one of the frequent complications in patients undergoing surgical operations. Staphylococcus aureus is the most common cause of surgical wounds. Artemisia absinthium has been shown to bear strong antimicrobial activity, especially against Gram-positive pathogens. This study was designed to investigate the antimicrobial effects of A. absinthium against surgical wounds infected by S. aureus in a rat model. Twenty male Sprague-Dawley rats were divided randomly into two equal groups of treated and control rats. A circular incision was created on the dorsal inter-scapular region of each rat. After skin wounding, rats were inoculated locally with 1 × 10 CFU of S. aureus at sites of skin wounds. The extract was applied topically twice a day throughout the experiment. Animals of the control group were left untreated. Results have revealed that topical application of A. absinthium extract on the infected wound sites produced significant antibacterial activity against S. aureus. [ABSTRACT FROM AUTHOR]