Antibiogram and Antibiotic Resistance Genes among Coagulase-Negative Staphylococci recovered from Bovine Mastitis

Abstract

M astitis is defined as inflammations of the udder tissues resulting in sever reduction of milk yield and quality and causing significant economic losses in the cattle worldwide (Gezgen and Seker, 2016). Also, mastitis defined as an inflammatory condition associated with high somatic cell count (SCC) levels and drop in milk production (Taponen et al., 2007).Staphylococci have been reported to be the most common bacterial cause of subclinical mastitis (Pitkälä et al., 2004). However, CoNS are typical common bovine pathogen involved in subclinical mastitis, particularly in heifer, and are research Article Abstract | Coagulase-negative Staphylococci (CoNS) have emerged as an important Staphylococci species implicated in bovine mastitis in dairy herds. This study was conducted to determine the prevalence, antibiogram, and antibiotic resistance genes among coagulase-negative Staphylococci recovered from cattle suffer from subclinical mastitis in Egypt. A total of 110 (36.7%) milk samples collected from 300 lactating cows were positive for the California mastitis test. On the Mannitol Salt Agar medium, out of 110 subclinical mastitis samples 62 (56.36%) were identified as CoNS isolates. Antibiotic sensitivity test conducted against nine types of antibiotics for CoNS strains that exhibited high susceptibility to most of the tested antibiotics, with particularly resistance pattern to oxicillin (41.9 %), and 11 (17.7%) CoNS isolate exhibited multidrug resistance (MDR). A total of 15 randomly selected isolates were subjected for detection of antibiotic-resistant genes among CoNS. The results indicated that mecA (73.3%) was the most identified gene, followed by tetK (60%) and ermB (13.3%) genes, whereas no detection for blaZ and vanA genes. In conclusion, our results indicate the importance of the regular surveillance of phenotypic and genotypic profiles of CoNS, isolates to ensure effective control measures and minimize the evolution of MDR strains and recommended the applying of antibiotic sensitivity test before treatment or random selection of antibiotics in field cases to avoid the emerging of resistance phenomena.

Molecular characterisation of antimicrobial resistance in coagulase negative staphylococci isolated from bovine subclinical mastitis

“…Similar to this findings, Krupa (2020) reported that CNS isolated from bovine SCM in Kerala showed resistance towards enrofloxacin, gentamicin, cotrimoxazole, tetracycline and methicillin with 48.15 per cent, 37.04 per cent, 29.63 per cent, 25.93 per cent and 14.81 per cent respectively. Walid et al (2021) reported that CNS isolated from bovine mastitis in Egypt was found to be susceptible to gentamicin, ciprofloxacin, amoxicillin/clavulanic acid, chloramphenicol, tetracycline, penicillin, vancomycin, and erythromycin, which is contrary to the findings in this study.…”

“…Based on the colony characteristics and biochemical tests, 49 isolates (44.95 per cent) were CNS in this study. It was in accordance with Walid et al (2021), who conducted a study on subclinical mastitis of cattle in Egypt, and revealed that CNS was isolated in 56.63 per cent of the positive samples. Similarly, Krupa (2020) found that 56.25 per cent of the isolates from bovine SCM in Kerala were CNS.…”

Genotypic characterization of mecA gene and antibiogram profile of coagulase-negative staphylococci in subclinical mastitic cows

“…Nayel et al [10] reported that the mecA gene was detected in 73.33% of CNS isolates from mastitic cows, and interestingly, 26.67% of mecA negative isolates were OX resistant phenotypically which is in agreement with our findings. Furthermore, Walid et al [36] reported that mecA was the most identified gene (73.3%) from CNS isolates that exhibited multidrug resistance (MDR) in bovine mastitis in dairy herds [36]. The present study shows a higher incidence of mecA than empirical research, which effectively detected mecA with prevalence rates of 9.7% [37].…”

Correlation between biofilm formation and antibacterial resistance pattern among coagulase negative Staphylococcus.

“…S. haemolyticus, S. chromogenes, and S. warneri were the only species identified from clinical mastitis. Walid (2021) recorded that most CNS isolates from bovine mastitis in Egypt were S. epidermidis (48.4%), S. saprophyticus (32.3%), and S. haemolyticus In particular, several CNS, such as S. epidemidis, S. chromogenes, and S. xylosus, showed higher pathogenicity by forming biofilms for bacterial aggregation for better growth and resistance to adverse conditions (Maity and Ambatipudi, 2021). In the current study, biofilm formation ability was investigated in all tested CNS isolates that showed hemolytic activity, revealing that all CNS isolates have the ability for biofilm production with a percentage of 100% but to a different degree.…”