Staphylococcus aureus

Staphylococcus aureus: Stap sector (staphylococci), large light pink colonies with sheen, No. 4; Streptococcus parauberis: Strep sector (streptococci), small violet colonies, No. 5.

Staphylococcus aureus (or “Golden Staphylococcus”) is also called “the king of purulent processes”. It is biochemically very active, produces large numbers of toxins, is well adapted to living on skin and mucous membranes and causes variety of pyogenic (purulent) infections in both animals and humans. Staphylococcus aureus is also able to multiply well in food, tolerates high content of table salt and some strains release large amounts of toxins into food resulting in vomiting and diarrhoea after ingestion.  

Mastitis caused by the golden staphylococcus can be acute or chronic with varied signs of inflammation up to severe purulent mastitis. Staphylococcal mastitis is prone to recurrence because S. aureus survives therapy in upper parts of the mammary gland.

Staphylococci are extremely resistant thus they persist in the environment for a long time. They also occur in healthy humans, e. g. in a nasal cavity (in 30 – 50% of people), on a skin, in bacterial populations of tonsils etc. If the person is healthy, staphylococci do not threaten him/her, but on the contrary, they act as a training for the immune system.

Staphylococcus aureus is the second most common cause of mastitis in dairy cows in our conditions (15 – 20% of cultivation findings). Another infected cow, cracked rubbers of teat cups where staphylococci persist, bacteria surviving in the environment and also tiny injuries of hands of milkmaids where staphylococci multiply are the sources of these bacteria.  

Staphylococci are bacteria typical of development of antibiotic resistance therefore it is necessary to promptly determine the causative agent of mastitis, make an antibiogram (susceptibility to antibiotics) and initiate a targeted therapy. 

Staphylococcus aureus will grow by the next day in the ClearMilk test on a farm. Our laboratory can confirm the result using the MALDI TOF machine; we also offer testing for susceptibility to antibiotics.

Quickness of diagnosis in infectious processes caused by Staphylococcus aureus microorganism is important; bacteria multiply very fast (one replication in ca. 20 minutes), produce enzymes and toxins and are very aggressive in the udder tissue.