Prevalence, risk factors and multidrug resistance profile of Staphylococcus aureus isolated from bovine mastitis in selected dairy farms in and around Asella town, Arsi Zone, South Eastern Ethiopia

Staphylococcus bacteria are often associated with subclinical bovine mastitis. This study aimed to identify multiresistant Staphylococcus spp. associated with subclinical mastitis and the associated risk factors. Twenty-three dairy farms with a history of decrease in milk production, located in the lower Acre region, Brazil, were selected. An epidemiological questionnaire was provided in all farms. All animals were examined using the California Mastitis Test (CMT) and their milk samples were collected for bacterial culture. After isolation and identification, the disk diffusion antimicrobial susceptibility test was performed against nine classes of antimicrobials. Of the 339 cows examined using the CMT, 108 had mastitis. A total of 229 milk samples were collected from individual teats. MALDI-TOF MS found isolates belonging to eight species of Staphylococcus, in 101 of these samples. S. chromogenes (58.4%) demonstrated strongest resistance to the nine classes of antimicrobial active principles. Nineteen isolates with multidrug resistance phenotypic profile were identified. This phenotypic expression indicates wide circulation of resistant genes in this species. The presence of multidrug resistance in Staphylococcus spp. in this study was correlated with lack of water for cleaning the corral, which is a preventive factor, minimizing the transmission and persistence of pathogens in the farms.

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Characterization of Staphylococcus aureus Isolates From Cases of Clinical Bovine Mastitis on Large-Scale Chinese Dairy Farms

Frontiers in Veterinary Science ◽

10.3389/fvets.2020.580129 ◽

2020 ◽

Vol 7 ◽

Author(s):

Kangjun Liu ◽

Luyao Tao ◽

Jianji Li ◽

Li Fang ◽

Luying Cui ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Cluster Analysis ◽

Antimicrobial Resistance ◽

Large Scale ◽

Bovine Mastitis ◽

Dairy Farms ◽

Clinical Mastitis ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Tof Ms

Bovine mastitis is a prevalent disease that causes serious economic problems globally in the dairy industry. Staphylococcus aureus is an important pathogen of bovine mastitis. This study was conducted to characterize S. aureus isolates from clinical bovine mastitis cases in large-scale dairy herds in China. S. aureus was isolated from 624 clinical mastitis cases and confirmed by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). In total, 62 S. aureus isolates were obtained. Cluster analysis, genetic diversity, quantification of biofilm formation, antimicrobial resistance, and detection of virulence genes were performed on these isolates of S. aureus. Eight isolates harbored the mecA gene and were sensitive to oxacillin. MALDI-TOF MS cluster analysis revealed that the 62 isolates were divided into three major clusters (I, II, III) and eight main groups (A–H) at the distance level of 700. The agr II was the most prevalent (56.5%). The 62 S. aureus isolates were assigned to seven spa types. The most common spa type was t529(58.1%), followed by t2196 (14.5%), t518 (14.5%), t571(6.5%), t034 (3.2%), t2734 (1.6%), and t730 (1.6%). Five STs were identified from seven representative isolates as follows: ST630/CC8, ST97/CC97, ST50, ST398, and ST705. All isolates had the ability to form biofilm. Antimicrobial resistance was most frequently observed to ciprofloxacin (29%), followed by penicillin (24.2%), and streptomycin (9.6%). All isolates harbored the fnbA, clfB (100%), icaA, and icaD genes. This study provides the basis for the development of bovine mastitis prevention program on large-scale dairy farms.

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Milk Safety Assessment, Isolation, and Antimicrobial Susceptibility Profile of Staphylococcus aureus in Selected Dairy Farms of Mukaturi and Sululta Town, Oromia Region, Ethiopia

Veterinary Medicine International ◽

10.1155/2019/3063185 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Sema Regasa ◽

Shimelis Mengistu ◽

Ashebr Abraha

Keyword(s):

Risk Factors ◽

Staphylococcus Aureus ◽

Antimicrobial Susceptibility ◽

Dairy Farms ◽

Raw Milk ◽

Penicillin G ◽

Human Consumption ◽

Milk Consumption ◽

Cross Sectional ◽

Antimicrobial Susceptibility Profile

A cross-sectional study was conducted to estimate the prevalence of Staphylococcus aureus in raw milk and swab, to assess the antimicrobial susceptibility profile, milk handling practice, and its associated risk factors in selected dairy farms of Mukaturi and Sululta Town, Oromia Region, Ethiopia. A total of 247 samples collected from dairy farms were examined using standard microbiological techniques. The antimicrobial susceptibility profiles of the isolates were also investigated. The possible risk factors for Staphylococcus aureus contaminations in milk were evaluated through a structured questionnaire. Overall, 16.6% (n= 41) of the samples were positive for S. aureus. The prevalence of S. aureus was 15.3% from udder milk and 25%, 20%, and 10% from milkers’ hand, milking bucket, and drying towel swab, respectively. The prevalence of Staphylococcus aureus in milk showed statistically significant variation with respect to age (p≤ 0.001), parity (P≤ 0.001), drainage condition of milking area (P=0.035), study sites (P=0.035), and management system (P=0.035). Majority of the isolates were found resistant to penicillin G (97.6%) and amoxicillin (43.9%). According to this study, 12/28(42.9%) Staphylococcus aureus positive raw milk samples had 104-105cfu/ml S. aureus count, which is above the recommended level for human consumption. 47.1% of milking persons store milk at room temperature temporarily (between 6 and 12 hrs) till transport to collection center with no means of cooling aid. From consumers 25.6% had no health risk associated with raw milk consumption or aware of milk borne disease associated with drinking raw milk. Thus, 60.5% of milk users had habit of raw milk consumption. The study revealed a prevalence of S. aureus, poor milk handling practices, raw milk consumption behavior in study area. Proper handling and hygiene decrease milk contamination by S. aureus and make it safe for human consumption.

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Risk factors associated with the antimicrobial resistance of Staphylococcus aureus isolated from bovine mastitis

Pesquisa Veterinária Brasileira ◽

10.1590/s0100-736x2014001000004 ◽

2014 ◽

Vol 34 (10) ◽

pp. 947-952 ◽

Cited By ~ 4

Author(s):

Daniele C. Beuron ◽

Cristina S. Cortinhas ◽

Bruno G. Botaro ◽

Susana N. Macedo ◽

Juliano L. Gonçalves ◽

...

Keyword(s):

Risk Factors ◽

Staphylococcus Aureus ◽

Antimicrobial Resistance ◽

Antimicrobial Susceptibility ◽

Management Practices ◽

Bovine Mastitis ◽

Factors Associated ◽

Milk Samples ◽

Treatment Procedures

The objective of this study was to evaluate herd management practices and mastitis treatment procedures as risk factors associated with Staphylococcus aureus antimicrobial resistance. For this study, 13 herds were selected to participate in the study to evaluate the association between their management practices and mastitis treatment procedures and in vitro antimicrobial susceptibility. A total of 1069 composite milk samples were collected aseptically from the selected cows in four different periods over two years. The samples were used for microbiological culturing of S. aureus isolates and evaluation of their antimicrobial susceptibility. A total of 756 samples (70.7%) were culture-positive, and S. aureus comprised 27.77% (n=210) of the isolates. The S. aureus isolates were tested using the disk-diffusion susceptibility assay with the following antimicrobials: ampicillin 10mg; clindamycin 2μg; penicillin 1mg; ceftiofur 30μg; gentamicin 10mg; sulfa-trimethoprim 25μg; enrofloxacin 5μg; sulfonamide 300μg; tetracycline 30μg; oxacillin 1mg; cephalothin 30μg and erythromycin 5μg. The variables that were significantly associated with S. aureus resistance were as follows: the treatment of clinical mastitis for ampicillin (OR=2.18), dry cow treatment for enrofloxacin (OR=2.11) and not sending milk samples for microbiological culture and susceptibility tests, for ampicillin (OR=2.57) and penicillin (OR=4.69). In conclusion, the identification of risk factors for S. aureus resistance against various mastitis antimicrobials is an important information that may help in practical recommendations for prudent use of antimicrobial in milk production.

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