Table 4-3.

Common Bacterial Culture Results

Site	Commensals	Pathogens
External ear canal
Dog	Malassezia, Clostridium,  Staphylococcus (a few),  Bacillus (a few); never  Streptococcus,  Pseudomonas, or Proteus	Many Staphylococcus and Malassezia together; Pseudomonas, Proteus, Streptococcus, Escherichia coli
Cat	Not documented	Staphylococcus aureus, β-hemolytic streptococci, Pasteurella, Pseudomonas, Proteus, E. coli, Malassezia
Skin
Dog	Micrococcus, Clostridium,  diphtheroids, Staphylococcus  epidermidis, Corynebacterium,  Malassezia	S. aureus (coagulase positive), Proteus, Pseudomonas, E. coli
Cat	Micrococcus, Streptococcus,  S. aureus, S. epidermidis	S. aureus, Pasteurella multocida, Bacteroides, Fusobacterium, hemolytic streptococci
Conjunctiva	Staphylococcus, Streptococcus,  Bacillus, Corynebacterium,  diphtheroids, Neisseria,  Pseudomonas	S. aureus, Bacillus, Pseudomonas, E . coli, Aspergillus
Vagina	Staphylococcus, Streptococcus,  Enterococcus, Corynebacterium,  E. coli, Haemophilus, Pseudomonas, Peptostreptococcus, Bacteroides	Brucella canis; pure culture of organism (especially E. coli, Staphylococcus, Pseudomonas) when accompanied by tissue reaction at vaginal cytology
Urine	<1000* organisms per milliliter; presence of several organisms suggests contamination	More than 100,000* organisms per milliliter and often pure culture; E. coli, enterobacteria, Klebsiella, Proteus, Pseudomonas aeruginosa, P. multocida, Staphylococcus, Streptococcus

^*Absolute numbers of bacteria depend on the collection technique.