Background: Antibiotics have long been the first line of defense to prevent Escherichia coli infections, but they have lost their potency since bacteria have grown increasingly resistant to treatment. The present research aimed to study the drug resistance and the prevalence of tetracycline resistance genes in E. coli isolated from broilers with colibacillosis. Results: The results showed that the most prevalent type of drug resistance was to tetracycline at 95.0%, and the least was to gentamicin at 21.7%. The prevalences of antimicrobial resistance among the tested antibiotics were significantly different (p < 0.001). A statistically significant difference was observed between the prevalence of the tet genes (p < 0.001). The tetD positive isolates and antibiotic sensitivity to tetracycline showed statistical significant differences (p = 0.017). Conclusions: Considering the results, tetA is the most common tetracycline resistance gene, and the presence of tetD and antibiotic sensitivity to tetracycline had a significant relationship in E. coli isolated from colibacillosis infections.

Infectious bronchitis (IB) is a highly contagious disease of the respiratory and urogenital tract of chickens, caused by infectious bronchitis virus (IBV), a member of the family Coronaviridae. The disease is common throughout the world where chickens are produced commercially. PCR on reverse transcribed RNA is a potent technique for the detection of IBV. In comparison with classical detection methods, PCR-based techniques are both sensitive and fast. Dozens of serotypes and genotypes of IBV have been detected, and many more will surely be reported in future. This research was conducted to identify the infectious bronchitis virus with group specific primers of avian Coronaviruses in Zabol, southeast of Iran. Tracheal swabs were collected from eleven commercial broiler flocks and these swabs were used for RNA extraction. General primers included XCE2+ and XCE2- that amplify all IBV serotypes were used. Primers MCE1+, BCE1+ and DCE1+ was used to amplifying the specific nucleotide sequence of Massachusetts, 4/91 and D274 serotypes, respectively. The results of this study showed that 36.36% of the sampled flocks were positive to IBV by RT-PCR. Moreover, the Massachusetts was the identified serotype of infectious bronchitis virus. The results provide the first molecular evidence for the presence of infectious bronchitis virus and Massachusetts serotype in Zabol.Electronic supplementary materialThe online version of this article (doi:10.1186/2193-1801-2-36) contains supplementary material, which is available to authorized users.

Background: Zoonotic food-borne pathogens such as Salmonella spp., which can be hosted by some raw foods, play a crucial role in ranking the public health of a country Objectives: The present study was conducted to assess the frequency, antibiotic resistance pattern and index of multiple antibiotic resistance (MAR) of Salmonella spp. in chicken meat Methods: A cross-sectional survey was conducted from October 2017 to March 2018.One-hundred and fifty chicken meat samples were collected from meat stores in Zahedan, southeast of Iran and screened for contamination with Salmonella spp. using the polymerase chain reaction assay targeting the inv-A gene. Antimicrobial susceptibility testing was performed against 11 commonly prescribed antimicrobial agents in the veterinary treatment to calculate the MAR index Results: The contamination rate was 2.7% (4/150). The antimicrobial resistance rate was 100% (n = 4) against penicillin, tylosin, tetracycline, erythromycin and tiamulin, 50% (n = 2) against trimethoprim/sulfamethoxazole, difloxacin and lincomycin/spectinomycin and 25% (n = 1) against flumequine and florfenicol. All isolates were sensitive to fosfomycin. Interestingly, all isolates (n = 4) exhibited different MAR patterns. Furthermore, the MAR index ranged from 0.45 to 0.81 Conclusions:In addition to the MAR index, which indicated that the isolate originated from a source where antibiotics were used to a great degree and/or in large amounts, the results showed that the chicken meat hosted resistant strains of Salmonella spp. in the study area. Overall, the findings indicated an important public health problem. To reduce this alarming signal, the poultry industry should implement control measures in the study area.

Background: Nowadays, the demand for antibacterial fabrics has increased. White alum is used for oral aphthous ulcers treatment in traditional medicine of Sistan city, Sistan and Baluchistan Province, Iran, and also as a flocculent for water purification. This study is aimed to evaluate the effect of concentration and time on antibacterial activity of white alum on Escherichia coli O157:H7. Materials and Methods: 0.25, 0.5, 1 and 2% concentrations of white alum were added to 10 8 CFU of Escherichia coli O157:H7. Optical Density was recorded for 4 hours. Data obtained were analyzed using Repeated Measure and Oneway ANOVA by SPSS. Results: Results revealed the effectiveness of white alum in the growth of the tested bacterium. The white alum was found to be potent against Escherichia coli O157:H7 at a concentration above 1% (p<0.05). Also, its effect is dose and time dependent, as well as other disinfectants. Conclusion: A wide variety of natural products has been under scrutiny for their clinical potential, both in terms of prevention and treatment. Strong antibacterial activity of white alum compared with control was shown against tested bacterium. In conclusion, white alum can be used as an inhibitor of bacterial growth, especially for Escherichia coli O157:H7.

This study was aimed to survey the prevalence of Salmonella spp. in water sources of Sistan and Baluchistan Province, Iran. Total 100 samples were collected from different sites and divided on the basis of potability, geographic location, accessibility, consumption and water flow types. Protocols issued by Institute of Standards and Industrial Research of Iran were used to detect Salmonella spp. Results of study revealed that 74.6% water sources shows the presence of Salmonella spp. Among studied sources, only one sample of potable water was contaminated with Salmonella spp. The highest contamination was reported from still water and it was significantly different that the pipe water (p<0.05). The highest contamination among non-potable water was reported from Jazinak compared to other regions. Further, it was reported that non-potable water is mostly used for non-agricultural consumption and it was found to be more polluted than water used for irrigation (p<0.05). The highest contamination with Salmonella was reported in ponds water (p<0.05). Non-potable water collected from east region of Sistan was reported more polluted than the west region. Contamination of non-potable water resources in the study area was high. Potable water, totally, indicates the proper function of the Salmonella treatment plan of water refinery of Sistan. Non-potable water of study area is polluted. Identification of Salmonella serotype and antibiotic susceptibility testing serve as indicators to define the accurate level of contamination.