Characteristic profiles of biofilm, enterotoxins and virulence of Staphylococcus aureus isolates from dairy cows in Xinjiang Province, China

• Published in: Journal of veterinary science (Suwŏn-si, Korea) 2019, 20(6), , pp.74-
• Main Authors: Wu, Yehui, Li, Jing, Qiao, Mengfan, Meng, Dan, Meng, Qingling, Qiao, Jun, Zhang, Xingxing, Wang, Lixia, Cai, Kuojun, Zhang, Jinsheng, Zhang, Zaichao, Yu, Weiwei, Cai, Xuepeng
• Format: Article
• Language: English
• Subjects: Animals; Anti-Bacterial Agents - pharmacology; Biofilms; Cattle; Cattle Diseases - microbiology; China; Dairying; Drug Resistance, Bacterial - genetics; Enterotoxins - chemistry; Female; Original; Staphylococcal Infections - microbiology; Staphylococcal Infections - veterinary; Staphylococcus aureus - drug effects; Staphylococcus aureus - genetics; Staphylococcus aureus - pathogenicity; Staphylococcus aureus - physiology; Virulence; 수의학
• ISSN: 1229-845X; 1976-555X
• DOI: 10.4142/jvs.2019.20.e74

As an important zoonotic pathogen, has led to serious mastitis and endometritis in infected dairy cows. In this study, a total of 164 strains of were isolated from dairy cows in Xinjiang Province, China, and subjected to assays to determine drug susceptibility and biofilm (BF) formation ability. Enterotoxin-related genes were detected, and the transcription levels of genes related to BF formation were determined by using reverse transcription-quantitative polymerase chain reaction. Moreover, the pathogenicity of isolates with different BF formation abilities was determined by measuring their hemolysis activity, half lethal dose (LD ) and organ bacterial load. The results showed that 86.0% of isolates could form BF. Among them, 42.1% of the strains had weak BF formation ability, and most strains with a strong BF formation ability were gene carriers. The isolates displayed multidrug resistance and their drug resistance was positively correlated with their BF formation ability. Moreover, 96.3% of the isolates carried enterotoxin genes. Among them, the detection rates of the novel enterotoxin genes were higher than those of conventional enterotoxin genes. Furthermore, isolates with a strong BF formation ability had higher LD50 but lower hemolysis ability and organ bacterial load than those of the isolates with weak or no BF ability. However, isolates without BF ability produced more severe pathological changes than those of isolates with strong BF formation ability. These findings suggest that higher BF ability and presence of novel enterotoxin genes are important characteristics of isolates from dairy cows in Xinjiang Province, China, and such isolates may pose potential threats to food safety.