Isolation and characterization of Staphylococcus aureus from raw cow milk in Bangladesh

The study was intended for identification and characterization of Staphylococcus aureus isolated from raw cow milk. A total of 47 milk samples were collected from Sheshmore, Shutiakhali and Bangladesh Agricultural University Dairy Farm, Mymensingh. Using bacteriological, biochemical and PCR-based identification schemes, 12 (25.53%) isolates were confirmed as S. aureus. All the isolates showed ?-hemolysis on 5% sheep blood agar. S. aureus specific nuc gene (target size 279-bp) was amplified in the cases of all isolates. The isolates were found as resistant to Penicillin (100%), Erythromycin (75%) and Amoxicillin (100%). On the other hand, the isolates were sensitive to Ciprofloxacin (83.33%), Oxacillin (100%), Cloxacillin (100%) and Neomycin (100%). The isolated S. aureus showed increased resistance to broad spectrum antibiotic (e.g., Ciprofloxacin). As many people have a tendency to drink raw milk and raw milk products, there is high risk of S. aureus infection in human

Prevalence and Antibiotic Resistance Pattern of Escherichia coli Isolated from Raw Dairy Milk

E. coli is one of the most important food borne pathogen, which could be transmitted by milk and milk products. To assess the role of dairy milk as the source of drug resistant E. coli, we examined 50 raw dairy milk samples (25-farm milk + 25-market milk) from some selected areas of Bangladesh by cultural, morphological, biochemical and antimicrobial sensitivity tests. In the preliminary observation, the mean total aerobic mesophilic count of market and farm raw milk samples were 8.98 and 8.68 log CFU/ml, while mean coliform count were 4.20 and 3.03 log CFU/ml respectively. Thirty-three E. coli isolates were recovered from collected samples (66% 33 of 50) and this pathogen was more prevalent in market milk (76%, 19 of 25) than farm milk (56%, 14 of 25). In addition, most of the isolated E. coli exhibited resistance against ampicillin and cefotaxime. This result shows that, the raw dairy milk and its products could be a source of human drug resistant E. coli

Factors associated with repeated outbreak of anthrax in Bangladesh: qualitative and quantitative study

Anthrax, caused by Bacillus anthracis is an acute, febrile disease of warm blooded animals including humans. Social norms and poverty in addition to climatic factors such as soil conditions, seasons of year, ambient temperature and rainfall influence the persistence of the B. anthracis and anthrax outbreaks. The present study was designed to reveal the factors influencing the repeated outbreak of anthrax in Bangladesh. Considering the previous outbreaks of anthrax, Sirajganj, Bogra, Kushtia, Tangail and Mymensingh districts of Bangladesh were selected for this study. To elucidate the factors, qualitative data relating to the animal management, knowledge and behavior of the people; and quantitative data relating to soil conditions, ambient temperature and rainfall were acquired, and analyzed critically. Based on the outbreak histories, a year was divided into two seasons, anthrax prone season (May-November) and anthrax dry season (December-April). Anthrax spores could be isolated from 11.67% (n=14/120) of the soil samples collected from the study areas. The present study revealed that poor knowledge, lack of awareness, improper carcass disposal, inadequate vaccination, high Ca content and moisture in the soil along with high ambient temperature and rainfall during the anthrax prone season were the possible influencing factors of repeated outbreaks of anthrax in the study areas. Intensive propaganda to create public awareness of anthrax together with proper vaccination may reduce anthrax outbreaks in Bangladesh

Reverse transcription polymerase chain reaction (RT-PCR) based detection and serotyping of FMD Virus from field samples of Gazipur, Bangladesh, and adaptation of the virus in BHK-21 cell

The study aimed for the detection and serotyping of Foot and Mouth Disease virus (FMDV) circulating in Kapasia Upazila, Gazipur district of Bangladesh during 2013. Twelve samples comprising of tongue epithelium (n=8) and inter digital tissue (n=4) were collected from suspected cattle, and inocula were prepared. The inocula were inoculated into confluent BHK-21 cell line for virus propagation. After 3 subsequent passages; progressive cytopathic effects (CPE) specific for FMDV i.e., rounding and flattening of cells, breaking down of the intercellular bridge and finally cell death (almost 100%) were observed; these were indicative of successful virus propagation in the cells. Viral RNA was extracted, and Reverse Transcription Polymerase Chain Reaction (RT-PCR) was performed using three sets of primers corresponding to the serotype and lsquo;O', and lsquo;Asia-1' and and lsquo;A', respectively. Out of the 12 samples, 10 (83.33%) were found to be positive for FMDV, and all of those were of serotype and lsquo;O'. It is concluded that FMDV serotype and lsquo;O' is circulating among the cattle of Gazipur district, Bangladesh. [J Adv Vet Anim Res 2015; 2(3.000): 291-295

PCR Based Detection of Shiga Toxin Producing E. coli in Commercial Poultry and Related Environments

Shiga toxin (Stx)-producing E. coli (STEC) is the most important foodborne pathogen which is the causal agent of mild diarrhea, bloody diarrhea, hemolytic-uremic syndrome (HUS) in human. The present study was designed to determine the prevalence and identification of Shiga toxin (Stx)-producing E. coli in poultry, detection of its source of infection in poultry and transmission pattern to human. For this purpose a total of 150 samples (cloacal swab-60, feed -15, water-15 and egg -60) were collected and analyzed in bacteriology laboratory by cultured in different bacteriological media followed by gram’s staining, biochemical tests and Polymerase Chain reaction (PCR). The PCR was performed by targeting 16s rRNA gene and shiga toxin producing gene in E. coli. Out of 150 collected samples, E. coli was found in 81 (54%) samples. Presence of E. coli was 100% in both feed (n=15) and egg (n=60), whereas 10% in cloacal swab (n=6). Water samples were totally free of E. coli. The stx2 gene was detected in all samples whether all samples were negative for stx1 gene. The study revealed that, poultry feed acts as a source of E. coli infection in poultry, which may be transmitted to environment and human via meat or eggs. Antibiotic sensitivity test revealed that isolated bacteria were highly sensitive to Ciprofloxacin

Antibiotic resistance profile of bacteria isolated from raw milk samples of cattle and buffaloes

Objectives: The objective of this study was to isolate and identify Staphylococcus aureus and Escherichia coli from raw milk samples of cattle and buffalo, and to evaluate the antibiotic sensitivity pattern. Materials and methods: A total of 34 milk samples were collected twice from 17 different healthy cattle (n=14) and buffaloes (n=3) at one-month interval, and analyzed in laboratory by staining, cultural and biochemical characteristics followed by polymerase chain reaction targeting nuc gene of S. aureus and 16 S rRNA of E. coli. Antibiotic sensitivity pattern of the isolated bacteria was assessed using the disc diffusion method. Results: Confirmation of the isolates as S. aureus and E. coli were carried out by PCR using nuc gene, 16S rRNA gene specific primers specific for S. aureus and E. coli respectively. A total of 12 samples (35.29%; 11 from cattle, 1 from buffalo) were found to be positive for S. aureus; 5 and 7 during first and second month, respectively. The E. coli were found in three samples (2 from cattle, 1 from buffaloe); one in first month and two in the second month. The antibiotic sensitivity test using 4 commonly used antibiotics indicated that the most of the isolates were resistant to Gatifloxacin and one isolate showed intermediate resistance to Ofloxacin while sensitive to Ciprofloxacin and Levofloxacin. Conclusion: Two different species of bacteria i.e., S. aureus and E. coli are contaminating with milk samples. The pathogenic bacteria can be controlled effectively by using Ciprofloxacin and Levofloxacin in the case of mastitis in cattle and buffaloes in Bangladesh. [J Adv Vet Anim Res 2016; 3(1.000): 62-67

Prevalence and characteristics of Shiga-toxin producing Escherichia coli (STEC) isolated from beef slaughterhouse

Objective: Shiga-toxin producing Escherichia coli (STEC) is the most important foodborne bacterial pathogen worldwide and the bovine animals are assumed as a reservoir of this pathogen. The present study was conducted to assess the role of bovine animals as the source of STEC. Materials and methods: To assess the role of bovine animals as the source of STEC, we examined 100 samples (50 rectal swab and 50 beef samples) collected from the local beef slaughterhouses by cultural, morphological, biochemical tests and polymerase chain reaction. Finally, the drug resistance pattern of isolated organisms has been examined. Result: In the preliminary screening by polymerase chain reaction (PCR), E. coli was more prevalent in rectal swab (n=21/50) than beef samples (n=16/50). Among 39 isolated E. coli, 10 isolates were confirmed as STEC (Rectal swab=7, Beef=3) by PCR, where stx2 gene (n=7/10) was predominant than stx1 gene (n=3/10). Remaining 29 isolates did not react to stx primers in PCR. Presence of STEC in beef samples was significantly associated with the fecal contamination at P≤0.1 (0.074818) in Pearsons correlation coefficient method. In addition, most of the isolated STEC strains were resistant to one or more commonly used antimicrobials in the country. Conclusion: The bovine animals and its products could be an important source of multidrug-resistant STEC in the country. [J Adv Vet Anim Res 2018; 5(2.000): 218-225

Prevalence and characterization of multi-drug resistant Salmonella Enterica serovar Gallinarum biovar Pullorum and Gallinarum from chicken

Aim: Salmonella is an important zoonotic pathogen responsible for animal and human diseases. The aim of the present study was to determine the prevalence and stereotyping of Salmonella isolates isolated from apparently healthy poultry. Furthermore, the clonal relatedness among the isolated Salmonella serovars was assessed. Materials and Methods: A total of 150 cloacal swab samples from apparently healthy chickens were collected, and were subjected for the isolation and identification of associated Salmonella organisms. The isolated colonies were identified and characterized on the basis of morphology, cultural characters, biochemical tests, slide agglutination test, polymerase chain reaction, and pulsed-field gel electrophoresis (PFGE). Antibiotic sensitivity patterns were also investigated using commonly used antibiotics. Results: Of the 150 samples, 11 (7.33%) produced characteristics pink colony with black center on XLD agar medium, and all were culturally and biochemically confirmed to be Salmonella. All possessed serovar-specific gene SpeF and reacted uniformly with group D antisera, suggesting that all of the isolates were Salmonella Enterica serovar Gallinarum, biovar Pullorum and/or Gallinarum. Antimicrobial susceptibility testing revealed that 54.54% of the isolated Salmonella Enterica serovars were highly sensitive to ciprofloxacin, whereas the 81.81% isolates were resistant to amoxycillin, doxycycline, kanamycin, gentamycin, and tetracycline. Pulsed-field gel electrophoresis of the XbaI-digested genomic DNA exhibited identical banding patterns, suggesting that the multidrug resistant Salmonella Enterica serovars occurring in commercial layers are highly clonal in Bangladesh. Conclusion: The present study was conducted to find out the prevalence of poultry Salmonella in layer chicken and to find out the clonal relationship among them. The data in this study suggest the prevalence of Salmonella Enterica, which is multidrug resistant and highly clonal for commercial layers of Bangladesh