Characterization and pathogenicity of multidrug-resistant coagulase-negative Staphylococci isolates in chickens

Abstract

The pathogenic potential of vancomycin and methicillin-resistant coagulase-negative Staphylococci (VMRCoNS) on Egyptian poultry farms has received little attention. Therefore, this study aims to study the prevalence of CoNS in imported poultry flocks and commercial poultry farms, evaluate the presence of virulence and antibiotic resistance genes (sea, seb, sec, sed, see, and mecA), and assess their pathogenicity in broiler chicks. Seven species were identified among 25 isolates, such as 8 S. gallinarum, 5 S. saprophyticus, 5 S. chromogens, 3 S. warneri, 2 S. hominis, 1 S. caprae, and 1 S. epidermidis. All isolates were resistant to clindamycin, doxycycline, vancomycin, methicillin, rifampicin, and penicillin. The mecA gene was confirmed in 14 isolates, while the sed gene was revealed in seven isolates. Commercial 1-day-old Ross broiler chicks were divided into eight groups of three replicates (10 birds/group): group Ӏ was negative control; groups (П, Ш, IV, V, VI, VII, and VIII) were subcutaneously inoculated with 108 CFUml−1 of S. hominis, S. caprae, S. epidermidis, S. gallinarum, S. chromogens, S. warneri, and S. saprophyticus, respectively. Groups VIII and V had mortality rates of 100% and 20%, respectively, with no evidence of mortalities in the other groups. The highest re-isolation of CoNS species was recorded in groups VII, VIII, and V. Postmortem and histopathological examination revealed the common presence of polyserositis in the internal organs, and hepatic and myocardial necrosis in groups IV, V, and VI. These findings revealed the pathogenic potential of CoNS, so special attention must be directed toward their public health impact.

The Occurrence and Characteristics of Methicillin-Resistant Staphylococcal Isolates from Foods and Containers

“…Ltd.; Nashik, India). Food product samples were collected in accordance with Sorour et al [ 26 ]. The samples were transferred to the laboratory in sterile plastic bags.…”

“…Numerous studies have demonstrated the presence of mec A-positive methicillin-resistant Staphylococcus aureus (MRSA) in various food sources, such as retail meat, fish, poultry, pork, beef, ready-to-eat foods, and even vegetables [ 11 , 19 , 20 , 21 ]. Additionally, CoNS carrying mec A, which are known for their increasing rates of methicillin resistance, have been detected in milk at a rate of 0.6% in Brazil and 6.7% in Tunisia [ 22 , 23 ], in ready-to-eat foods at a rate of 16.4% in Poland [ 24 ], and in meat at a rate 2.3–8% in Egypt [ 25 , 26 ], which raises additional concerns about the spread of resistance. In Thailand, the prevalence of MRA was found to be 20.5% in the university environment and 52.3% in the hospital environment [ 27 ].…”