Identification of staphylococci from bovine udders: evaluation of the API 20GP system

1986 ◽  
Vol 32 (4) ◽  
pp. 359-361 ◽  
Author(s):  
J. L. Watts ◽  
W. E. Owens ◽  
S. C. Nickerson
Keyword(s):  
Staphylococcus Aureus ◽  
Mammary Gland ◽  
Data Base ◽  
Poor Performance ◽  
Bovine Mammary Gland ◽  
Index Data

The API 20GP system (Analytab Products, Plainview, NY) correctly identified 56.1% of staphylococci isolated from the bovine mammary gland. The system identified 90.2% of Staphylococcus aureus strains, but failed to recognize strains of Staphylcoccus hyicus and others. Poor performance was attributed to the limited number of veterinary strains contained in the profile index data base. The API 20GP was determined to be an unacceptable method for identification of staphylococci isolated from the bovine mammary gland.

Phagocytosis of Staphylococcus aureus by bovine mammary gland macrophages and intracellular protection from antibiotic action in vitro and in vivo

1984 ◽  
Vol 51 (4) ◽  
pp. 513-523 ◽  
Author(s):  
Neil Craven ◽  
James C. Anderson
Keyword(s):  
Staphylococcus Aureus ◽  
Mammary Gland ◽  
Antibiotic Therapy ◽  
Bovine Mammary Gland ◽  
Lactating Cows ◽  
Colony Forming Units ◽  
Subsequent Exposure ◽  
Increased Sensitivity

SummaryMacrophages isolated from the involuted bovine mammary gland were cultured in vitro. Phagocytosis of opsonized Staphylococcus aureus occurred rapidly, but intracellular killing of bacteria was slow. Many intracellular staphylococci survived for up to 4 d exposure to extracellular cloxacillin and emerged from within the macrophages to multiply extracellularly when the antibiotic was inactivated. Rifampicin was significantly more efficient than cloxacillin in killing intracellular S. aureus after 18 h incubation, but it too failed to sterilize the cultures within 3 d. Staphylococci, which had remained viable within macrophages during 20 h incubation with extracellular cloxacillin, showed an increased sensitivity to dilute lysostaphin on subsequent exposure. A 3 d course of intramammary therapy with cloxacillin, commencing simultaneously with an infecting inoculum of ∼108 colony forming units (c.f.u.) S. aureus, apparently eliminated the infection from one quarter of the udders of each of three lactating cows, but bacteria were re-isolated from two cows after a delay of several days. However, when other quarters of the same cows were infected with ∼108 c.f.u. S. aureus which had been phagocytosed by autologous mammary macrophages, similar simultaneous antibiotic therapy failed to affect these infections. The in vitro and in vivo findings indicate the significance of intracellular survival of S. aureus as a factor contributing to failure of antibiotic therapy.

scholarly journals Effect of Staphylococcus aureus and Streptococcus uberis on apoptosis of bovine mammary gland neutrophils in vitro

2012 ◽  
Vol 50 (No. 1) ◽  
pp. 11-23 ◽  
Author(s):  
Z. Sladek ◽  
D. Rysanek ◽  
M. Faldyna
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Death ◽  
Mammary Gland ◽  
Programmed Cell Death ◽  
Propidium Iodide ◽  
Annexin V ◽  
Dna Fragments ◽  
Bovine Mammary Gland ◽  
Streptococcus Uberis

Neutrophils play an important role in the defence of the bovine mammary gland against bacterial infections. In the course of the resolution of mammary gland inflammation, neutrophils undergo programmed cell death – apoptosis. The aim of this study was to confirm whether the co-cultivation of neutrophils of the bovine mammary gland with either Staphylococcus aureus or Streptococcus uberis leads to signs of apoptosis. In the study, 16 mammary glands of four virgin heifers aged 16 to 18 months were examined. Neutrophils were obtained by lavage after an induced influx. After a three-hour incubation of the neutrophils with bacteria in vitro, neutrophil apoptosis was detected by morphological features, by determination of histone-associated DNA fragments (ELISA), and by Annexin -V and propidium iodide positivity (flow cytometry). S. aureus and S. uberis reduced the incidence of karyopycnotic and zeiotic neutrophils (P < 0.01), and insignificantly reduced the concentration of histone -associated DNA fragments (P > 0.05). The incubation of neutrophils with bacteria, however, increased the proportion of Annexin –V-positive cells (P < 0.01) and Annexin -V and propidium iodide-positive cells (P < 0.05). Co-cultivation of neutrophils with either S. aureus or S. uberis led to the induction of phosphatidylserine translocation characteristic of the early stage of apoptosis. The late signs of apoptosis were delayed by co-cultivation of neutrophils with both pathogens. Therefore it is obvious that although the programmed cell death of apoptosis is initiated by these pathogens, the completion of the program is delayed.

Role of several Staphylococcus aureus virulence factors on the inflammatory response in bovine mammary gland

2006 ◽  
Vol 40 (4) ◽  
pp. 177-183 ◽  
Author(s):  
Alfonso Zecconi ◽  
Lorenza Cesaris ◽  
Emmanouil Liandris ◽  
Valentina Daprà ◽  
Renata Piccinini
Keyword(s):  
Staphylococcus Aureus ◽  
Mammary Gland ◽  
Inflammatory Response ◽  
Virulence Factors ◽  
Bovine Mammary Gland
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