Thesis and Dissertations

Isolation, Identification, Antimicrobial Susceptibility Pattern and Molecular Characterization of Escherichia coli 0157:H7 Isolates from Beef at Butcher Shop in Bahir Dar City, Ethiopia

2022-02-23T00:00:00Z

Isolation, Identification, Antimicrobial Susceptibility Pattern and Molecular Characterization of Escherichia coli 0157:H7 Isolates from Beef at Butcher Shop in Bahir Dar City, Ethiopia Wogayehu Asefa Escherichia coli Ol 57:H7 serotype is worldwide zoonotic pathogenresponsible for the majority of severe cases of human enterohemorrhagic Escherichia coli. A cross sectional study was designed from November 2018-May 2019 to isolate, molecularly characterize E. coli serotype 0157:H7 and to assess its antimicrobial resistance pattern from rmv beef ready to eat "kurt "from butcher shop at Bahir Dar City. A total of 7 4 beef samples were collected and processed using standard microbiological procedures to isolate and identify the bacterium and determine their antimicrobial susceptibility patterns. Genomic DNA extracted from the isolates were examined in Polymerase Chain Reactions (PCR) to detect virulence genes (stxi and hlyA). Accordingly 21 E. coli Ol 57:H7 were isolated using compact dryEC kit and sorbitol maconky agar of which 61.9% stx, and 38.1%hlyA. Isolates were further subjected to the invitro antimicrobial sensitivity test and resulted in a degree of susceptibility ranged from 62% - 100% and resistance were between 4.8% and 33.3%. Only 6 (28.6%) of them showed the presence of resistance for two drugs amoxicillin and chloramphenicol. Finally the higher incidence of the stx, and hlyA gene isolated from meat samples in the butcher shop indicates a risk alert of E. coli 0157 infection. Therefore, appropriate measures are now needed to wards food safety.knowledge gap of butcher shop workers and building standardized abattoir in the area to prevent the spread of this life-threatening food borne disease in our city and our country Ethiopia having the habit eating uncooked beef

ISOLATION, IDENTIFICATION AND ANTMICROBIAL RESISTANCE PATTERNS OF METHICILLIN RESISTANT STAPHYIOCOCCUS AUREUS FROM RAW COW'S MILK IN DAIRY FARMS OF DEBRE MARKOS TOWN, NORTHWEST ETHIOPIA.

2022-02-23T00:00:00Z

ISOLATION, IDENTIFICATION AND ANTMICROBIAL RESISTANCE PATTERNS OF METHICILLIN RESISTANT STAPHYIOCOCCUS AUREUS FROM RAW COW'S MILK IN DAIRY FARMS OF DEBRE MARKOS TOWN, NORTHWEST ETHIOPIA. Haregua Yesigat A cross sectional study was conducted from November 2019 to April 2020 in Oebre Markos Town, to isolate and identify Methicillin Resistant Staphylococcus aureus from raw cow's milk and to evaluate their resistance pattern to different antimicrobials. Purposive sampling technique was employed and 50 dairy farms were involved in the study. From a total of 150 samples were collectedfrom pooled milk sample (50), milker's hand swab (50) and container swab (50). 14 (9.3%) of them were found to be positive for S. aureus. Out of 14 S. aureus isolates, 8(57.14%) tested positive for MRSA. Of which (8(57.14%)), 5 (62.5%), 2 (66.6%), and 1(33.3%) were from pooled milk; Hand swab from milker's and swab from containers, respectively. This study involved 50 respondents of milking persons who practiced udder washing (56%) and drying (52%) before milking, however; 96% did not use drying towel separately for the udder. while 80% did not practiced washing of hands between milking, 98% practiced washing of hands before milking. MRSA was identified using cefoxitin disk diffusion method. Of all S. aureus isolates, 57.14% were found resistance to cefoxitin. MRSA isolates were found to be sensitive to sulpha-trimethoprime (87.5%) and Gentamycin (87.5%) followed by Erythromycin (75%), ciprofloxacin (62.5%), chloramphenicol (62.5%). Lowest sensitivity was to tetracycline (25%). From all isolates of MRSA, 75 % of them developed multidrug resistance. In conclusion, this study showed the existence of MRSA in dairy farms of Debre markos town, where milker's hand and milking container were attributed to be the main source of contamination. Therefore milking should be practiced under personal and environmental hygienic conditions using clean and disinfected utensils.

ISOLATION, IDENTIFICATION AND ANTIMICROBIAL SUSCEPTIBILITY PATTERN OF STREPTOCOCCUS AGALACTIAE FROM BOVINE MASTITIC MILK IN AND AROUND BAHIR DAR, NORTH WEST ETHIOPIA

2021-08-11T00:00:00Z

ISOLATION, IDENTIFICATION AND ANTIMICROBIAL SUSCEPTIBILITY PATTERN OF STREPTOCOCCUS AGALACTIAE FROM BOVINE MASTITIC MILK IN AND AROUND BAHIR DAR, NORTH WEST ETHIOPIA Abebe Mihret Across-sectional study was conducted from November 2020 to April 2021in and around Bahir Dar dairy farms to isolate, identify and to determine antimicrobial susceptibility pattern of Streptococcus agalactiae from bovine mastitic milk. The samples were taken from clinically diseased and California Mastitis Test positive cows with Purposive sampling method. Isolation and identification of an organism was based on morphological, cultural and biochemical characteristics. A total of 123 lactating cows were tested for isolation and identification of the bacteria, of which 8 (6.50%) were clinical and 63 (51.22%) were sub-clinical mastitis. Those California Mastitis Test positive samples and samples from clinical samples were cultured on different culturing Medias. Out of the total 63 subclinical mastitis 9 samples and from 8 clinical mastitis 3 samples were further identified using primary and secondary biochemical tests. A total of 12/71 (16.90%) milk samples were shown typical catalase negative and CAMP test positive resulted in positive for Streptococcus agalactiae. The risk factors, breed, age, parity, and lactation stage, were found associated statistically significant (P<0.05) with the occurrence of mastitis due to Streptococcus agalactiae. The bacteria were 100% susceptible to vancomycin, erythromycin, and clindamycin. The microorganism was also sensitive to tetracyclin (91.67%), and ampicillin (83.33%). However, it was not susceptible to penicillin (100%). Regular antimicrobial susceptibility tests against Streptococcus agalactiae should be conducted in order to monitor the effectiveness of drugs against the pathogen. Veterinarians should be advised to use vancomycin, erythromycin, clindamycin and tetracyclin in dairy farms against mastitis caused by Streptococcus agalactiae. Key words: Bahir Dar; identification; isolation; mastitic milk; Streptococcus agalactiae

ISOLATION, IDENTIFICATION AND ANTIBIOTIC SUSCEPTIBLITY OF STAPHYLOCOCCUS AUREUS FROM MASTITIC MILK SAMPLES FROM DAIRY FARMS IN AND AROUND MOTTA TOWN, EAST GOJJAM ZONE, ETHIOPIA

2021-08-11T00:00:00Z

ISOLATION, IDENTIFICATION AND ANTIBIOTIC SUSCEPTIBLITY OF STAPHYLOCOCCUS AUREUS FROM MASTITIC MILK SAMPLES FROM DAIRY FARMS IN AND AROUND MOTTA TOWN, EAST GOJJAM ZONE, ETHIOPIA DENEKEW WUBETU A cross sectional study was conducted in and around Motta town, East Gojjam zone, Ethiopia from November 2020 to May 2021 in order to isolate, identify and determine the antibiotic susceptibilities of S. aureus isolated from mastitic cows. A total of 109 lactating cows were examined to detect clinical and subclinical mastitis by physical examinations of the udder, milk, and California mastitis test, respectively. The total proportion of mastitis was 62 (56.88%). Out of this, 4 (3.67%) and 58 (53.21%) were clinical and subclinical mastitis respectively with significant difference (p<0.05). Staphylococcus aureus was isolated at a rate of 25 (40.32%) from mastitic cows, out of this 1(25%) and 24 (41.38%) in clinical and subclinical mastitic cows respectively. The result showed that the occurrence of Staphylococcus aureus was2.118 times more likely to occur in sub clinical than clinical mastitis (OR= 2.118). Among the potential risk factors that were found to be associated with the S. aureus mastitis, cross breed (OR=2.226), old age (OR= 3.055), parity with many calves (OR= 3.120), late lactation stage (OR= 3.391), poor housing conditions (OR= 8.889), previous mastitis history (OR= 0.227) and sub clinical mastitis type (OR= 2.118) had high effect on the occurrence of S. aureus mastitis. However, breed and mastitis type had not been a significant potential risk factor for the occurrence of S. aureus mastitis (p<0.05). The present study showed that S. aureus was totally not susceptible to penicillin (0%) and intermediate susceptible to tetracycline (50%).However, S. aureus was found to be highly susceptible to gentamycin (93.75%), erythromycin (84.38%), clindamycin (90.36%) and trimethoprim (78.13%). In conclusion, Mastitis was found to be one of the major constraining factors that affect milk production in dairy cows in the study area. S. aureus is the major etiological agent of mastitis especially in sub clinical mastitis. Various risk factors that are listed above were found to be critical for the occurrence of S. aureus mastitis. Also S. aureus was found to be resistant to penicillin. Key words: Antibiotic susceptibility, Clinical mastitis, Mastitic cows, Risk factors, Subclinical mastitis, S. aureus