Bacteriology - gram positive cocci Flashcards
What are the main gram positive cocci?
Staphylococcus
Streptococcus
(Enterococcus)
What disease does staphylococcus cause?
Localised lesions - skin infections
What disease does streptococcus cause?
Generalised lesions - deeper eg. strangles, endocarditis
What does actinomyces cause?
Localised lesions - lumpy jaw
What does truperella cause?
Generalised lesions - skin necrosis and mastitis
How does dermatophilus cause disease?
Motile spores
What is the arrangement of staphylococci?
Irregular clump
WHat is the arrangement of streptococci?
Chain
Where is staph found?
In environment, on skin and mucous membranes
What type of staph is just in dogs?
Staph. pseudintermedius
What is the main staph which causes skin infection?
Staph. aureus
How does staph aureus appear in lab test?
Haemolytic
Gold more dangerous
What are the two types of haemolytic staph aureus?
Staph aureus alpha haemolysin and beta haemolysin
What type of haemolysis does each type of haemolytic staph aureus cause?
Alpha haemolysin - complete RBC lysis
Beta haemolysin - partial haemolysis
How does Staph aureus alpha haemolysin cause haemolysis?
Plasma membrane porin
How does Staph aureus beta haemolysin cause haemolysis?
Phospholipase C
What are the general types of disease associated with staphylococci?
Pyogenic skin infections Dermatitis Pyoderma Abcesses Systemic infections - septicaemia
How do you identify the type of streptococci?
Serotyping - Lancefield groups
Which one is catalase positive - staph or strep?
Staph
p is first so positive
What type of haemolysis does STREP alpha haemolysin cause?
Partial - opposite to STAPH
What type of haemolysis does strep beta haemolysin cause?
Full haemolysis - opposite to staph
What colour is associated with strep alpha haemolysin?
Green
Where is strep found?
Skin Mucosal membranes Upper resp tract GIT UGT
What type of staph causes disease in pigs?
Staph hyicus
What disease does staph hyicus cause?
Greasy pig disease - skin dries and falls off
What cocci causes suppurative arthritis in piglets?
Strep zooepidemicus
What cocci causes strangles like disease in piglets?
Strep porcinus
What is the most significant cocci in pigs?
Strep suis
What type of pathogen is strep suis?
An obligate pathogen - cant exist in environment
What disease does strep suis cause?
Local damage
Systemic spread by leucocytes
Meningitis/endocarditis/arthritis
What bacteria is the most common cause of mastitis in cattle?
Strep uberis
What bacteria causes strangyles in horses?
Streptococcus equi
WHat is strangles?
Infection of the lymphatics in horses head and neck
What causes resp tract infections in horses?
Strep pneumoniae
What causes GI tract infections in horses?
Strep zooepidemicus
What has less resistance to antibiotics - staph or strep?
Strep
What causes lumpy jaw in cattle?
Actinomyces bovis
How is lumpy jaw diagnosed?
Sulphur granules in pus
What disease does truperella pyogenes cause?
Summer mastitis
How does T pyogenes cause disease?
Enters via wounds eg. fly bites
What conditions are needed for T pyogenes?
Aerobic, raised CO2
What does dermatophilus congolensis cause?
Dermatitis - mud fever and rain scald
What is different about dermatophilus congolensis?
Uses zoospores
Mycelium in epidermis
Branching filaments
How is dermatophilus congolensis diagnosed?
Stain scabs for spores and filaments
How is dermatophilus congolensis treated?
Iodine and penicillin/streptomycin
