Presence of superantigen genes and antimicrobial resistance in Staphylococcus isolates obtained from the uteri of dairy cows with clinical endometritis

Abstract

Clinical endometritis is an important disease of dairy cattle and results in decreased reproductive performance. This disease is caused by contamination of the uterus with a broad spectrum of microorganisms after calving. In this study, staphylococcal isolates from the uterus of dairy cows with clinical endometritis were tested for their distribution of superantigen (SAg) genes and antimicrobial resistance. Between the 127 staphylococcal isolates collected in this study, 10 species were identified. The predominant strain identified was Staphylococcus aureus (n=53), followed by Staphylococcus saprophyticus (n=38) and Staphylococcus chromogenes (n=22). PCR analysis demonstrated that most isolates (63.0 per cent) harboured at least one SAg gene. The most commonly observed SAg gene and genotype was selj (38.6 per cent) and sec-selj-seln (24.0 per cent), respectively. Most isolates were resistant to penicillin (79.5 per cent), ampicillin (71.7 per cent), erythromycin (56.7 per cent), and tetracycline (52.0 per cent). PCR analysis demonstrated that the antimicrobial resistance determinants ermA, ermB, ermC, tetK, tetM and blaZ were detected in 0 per cent, 44.4 per cent, 51.4 per cent, 68.2 per cent, 13.6 per cent and 86.1 per cent of the erythromycin, tetracycline and β-lactam resistant isolates, respectively. There were 22 (17.3 per cent of all isolates) coagulase-negative staphylococci shown to be methicillin resistant. In the methicillin-resistant isolates, significant resistances to ampicillin, erythromycin and penicillin were observed (P<0.01). The results of this study demonstrate that staphylococci recovered from dairy cows with clinical endometritis contain an extensive and complex prevalence of SAg genes. Significant resistances to antibiotics were also seen, highlighting the need for the rational appliance of antibiotics in veterinary medicine.

Polydatin reduces Staphylococcus aureus lipoteichoic acid‐induced injury by attenuating reactive oxygen species generation and TLR2‐NFκB signalling

“…Staphylococcus aureus , a typical representative of Gram‐positive bacteria, is one of the major pathogens of many human and animal inflammatory diseases, including endometritis . LTA, a specific endotoxin embedded in the cell wall of S. aureus , has been reported to activate the inflammatory response .…”

“…Staphylococcus aureus ( S. aureus ) is an opportunistic Gram‐positive bacterium that causes various infectious diseases in humans and animals , such as skin and soft‐tissue infections , as well as pneumonia , sepsis and endometritis , and has led to high mortality. LTA is a teichoic acid extracted from the Gram‐positive bacteria cell wall that is the predominant driving force of the host inflammatory response to this type of bacteria .…”

Update on molecular diversity and multipathogenicity of staphylococcal superantigen toxins

“…Furthermore, recent studies (Fang et al 2019) demonstrated that SEC can directly cause inflammation, proinflammatory cytokine production and tissue damage in mammary glands, suggesting that SEC might play an important role in the development of mastitis associated with S. aureus infection. Clinical endometritis, which leads to decreased reproductive performance, is also an important disease in dairy cows (Jiang et al 2019;Zhao et al 2014). Zhao et al investigated SAg gene distribution of staphylococcal isolates in uterus of cows with clinical endometritis.…”

“…PCR analysis showed that most of isolates (63.0%) had at least 1 SAg gene. The most common SAg genes and genotypes were selj and sec-selj-sen (Zhao et al 2014). These results indicated that Staphylococci recovered from cows with clinical endometritis contained extensive and complex SAg genes, suggesting that SAg may contribute to the pathogenicity of bacteria in bovine endometritis.…”

IFN-τDisplays Anti-Inflammatory Effects onStaphylococcus aureusEndometritis via Inhibiting the Activation of the NF-κB and MAPK Pathways in Mice

“…S. aureus is a well-known gram-positive bacteria, which can lead to inflammation from both community-acquired and nosocomial infections [ 19 , 20 ]. S. aureus is also the main pathogenic microbe that causes endometritis and enhances the expression of proinflammatory cytokines [ 21 ]. It has been shown IFN- τ has immunomodulatory properties [ 22 ].…”