Antibiotic-resistant Escherichia coli (E. coli) are common in retail poultry products. In this study, we aimed to isolate and characterize multidrug resistant (MDR) E. coli in raw chicken meat samples collected from poultry shops in Sylhet division, Bangladesh, as well as to determine correlation between resistance phenotype and genotype. A total of 600 chicken meat swabs (divided equally between broiler and layer farms, n = 300 each) were collected and the isolates identified as E. coli (n = 381) were selected. Disc diffusion antimicrobial susceptibility assay showed resistance of these isolates to ampicillin, erythromycin, tetracycline, streptomycin, trimethoprim-sulfamethoxazole, chloramphenicol, and gentamicin. Polymerase chain reaction (PCR) identified several antibiotic resistance genes (ARGs) in our isolates. Among these ARGs, the prevalence of tetA (for tetracycline) was the highest (72.58%) in broiler chicken isolates, followed by sul1 (for sulfonamide; 44.16%), aadA1 (for streptomycin; 33.50%), ereA (for erythromycin; 27.41%), aac-3-IV (for gentamicin; 25.38%), and the two genes cmlA (24.87%) and catA1 (8.63%) for chloramphenicol. On the other hand, the respective prevalence in layer chicken isolates were 82.06%, 47.83%, 35.87%, 35.33%, 23.91%, 19.02%, and 5.43%. Furthermore, 49.23% of the isolates from broiler chicken were MDR, with the presence of multiple antibiotic resistance genes, including 3 (40.11%) and 4 (9.13%) genes. On the other hand, 51.09% of layer chicken E. coli isolates were MDR, with 3, 4 or 5 ARGs detected in 36.41%, 14.13%, and 0.54% of the isolates, respectively. We also found that 12.8% of broiler chicken E. coli isolates and 7.61% of layer chicken isolates carried genes coding for extended-spectrum SHV beta-lactamases. Lastly, we report the presence of the AmpC beta-lactamase producing gene (CITM) in 4.56% and 3.26% of broiler and layer chicken E. coli isolates, respectively. We found significant correlations between most of the antimicrobial resistant phenotypes and genotypes observed among the investigated E. coli isolates. Our findings highlight the need for the prudent use of antimicrobials in chickens to minimize the development of antibiotic-resistant bacterial strains.

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Background. This study investigates the viable persistence of avian influenza viruses (AIVs) in various types of artificially frozen environmental water and evaluates the feasibility of similar occurrence taking place in nature, and allowing for prolonged abiotic virus survival, with subsequent biotic viral recirculation. Methods. Fresh, brackish, and salty water, taken in Japan from aquatic biotopes regularly visited by migratory waterfowl, were seeded with AIVs. We monthly monitored the viability of the seeded viruses in the frozen state at −20°C and −30°C, for 12 months. We also monitored virus viability following repeatedly induced freezing and thawing. Results. The viruses exhibited considerable viable persistence all along that period of time, as well as during freezing-thawing cycles. Appreciable, yet noncrucial variances were observed in relation to some of the parameters examined. Conclusions. As typical waterborne pathogens of numerous northerly aquatic birds, AIVs are innately adapted to both the body temperature of their hosts (40°C to 42°C) and, presumably, to subzero temperatures of frozen lakes (down to −54°C in parts of Siberia) occupied and virus-seeded by subclinically infected birds, prior to freezing. Marked cryostability of AIVs appears to be evident. Preservation in environmental ice has significant ecophylogenetic and epidemiological implications, potentially, and could account for various unexplained phenomena.

Ceramic powder prepared by sintering of chicken feces, when mixed with avian influenza viruses or an avian adenovirus, inactivated these organisms to below detection levels. When the ceramic powder was mixed with double-distilled water, the pH of the water rose to 10 but the aqueous phase did not show any antivirus activity. After 10 washings with water or five washings with 1M Tris-HCl (pH 8.0), the ceramic powder still retained antivirus activity. Antivirus activity was not affected by the presence of organic material (33% fetal calf serum). When chicks were fed food containing 5% ceramic powder, there was no difference in body weight between normal feeding and the ceramic-mixture feeding. The mode of action of the ceramic powder remains unknown, but it possibly works by adsorbing the virus. These results show that the ceramic powder has antiviral activities and is a potentially useful tool against avian influenza on poultry farms.

Background and Aim: Pigeon rearing has been gaining popularity for recent years. They are reared remarkably very close to the house of the owner. This activity, therefore, may pose potential threats for humans as well as other animals as pigeons may carry and spread different pathogens including drug-resistant bacteria. This study was conducted to explore the prevalence of Escherichia coli and Salmonella spp. as well as their antibiogram profile along with an association analysis. Materials and Methods: Forty swab samples were collected from 20 pigeons during the study. E. coli and Salmonella spp. were isolated and identified on various types of agars, including MacConkey, Eosin methylene blue, Brilliant green, and Salmonella-Shigella agar. Biochemical tests such as the carbohydrate fermentation test, the triple sugar iron agar slant reaction, the indole test, the methyl red test, the catalase test, as well as the Voges–Proskauer test were also performed. Besides, the presence of E. coli was further confirmed by polymerase chain reaction (PCR). Moreover, antimicrobial susceptibility testing of the isolates was performed against nine antibiotics from seven classes on the Mueller-Hinton agar based on the Kirby–Bauer disk diffusion method. Results: The overall prevalence of E. coli and Salmonella spp. was 52.5 and 27.5%, respectively. The prevalence of the pathogenic E. coli was 61.90%. The antibiogram profile of 21 E. coli as well as 11 Salmonella spp. revealed that all isolates, except one, were resistant to one to six antibiotics. Around 61.90%, 71.43%, 23.81%, 61.90%, 23.81%, 19.05%, and 52.38% of E. coli showed resistance against amoxicillin, ampicillin, azithromycin, erythromycin, nalidixic acid, gentamicin, and tetracycline, respectively. Furthermore, E. coli resistance was not observed in case of ciprofloxacin and levofloxacin. Similarly, around 36.36%, 27.27%, 27.27%, 45.45%, 81.82%, 100%, and 18.18% of the Salmonella spp. showed resistance against amoxicillin, ampicillin, azithromycin, erythromycin, nalidixic acid, tetracycline, and levofloxacin, respectively. However, all Salmonella spp. (100%) were found to show sensitivity against ciprofloxacin and gentamicin. Multidrug-resistant (MDR) E. coli (23.80%) and Salmonella spp. (54.54%) were also isolated. Furthermore, both positive (odds ratio [OR] >1) and negative (OR <1) drug resistance associations, with a higher frequency of positive associations, were found in E. coli. A significant positive association was observed between ampicillin and amoxicillin (OR: 81.67, 95% confidence interval: 2.73-2447.57, p=0.01). Conclusion: Pigeon carrying MDR E. coli and Salmonella spp. may contribute to the transmission and spread of these microorganisms. Therefore, strict hygienic measures should be taken during the farming of pigeons to decrease the potential transmission of E. coli and Salmonella spp. from pigeon to humans as well as other animals. So far, this is the first report of the PCR-based identification of pathogenic E. coli from pigeons in Bangladesh.