Line 1: |
Line 1: |
| + | ===Characteristics=== |
| | | |
| + | *Formerly known as ''Actinomyces pyogenes'' and ''Corynebacterium pyogenes'' |
| + | *Small facultatively anaerobic rod |
| + | *Grows slowly on blood agar to produce small, white colonies surrounded by a zone of beta-haemolysis after 48 hours |
| + | *Produces hazy haemolysis after 24 hours; pin-point colonies after 48 hours |
| + | *Coryneform morphology, like Chinese characters; may be curved with slightly swollen ends |
| + | *Found in nasopharyngeal mucosa and genital tract of cattle, sheep, pigs |
| + | |
| + | |
| + | ===Pathogenicity=== |
| + | |
| + | *Opportunistic infections following injury or viral/mycoplasma infection in ruminants and pigs |
| + | *Extracellular toxins including haemolysin, proteases, DNase and neurominidase |
| + | *Haemolytic toxin, pyolysin, member of the thiol-activated cytolysins (pore-forming toxins); possibly cytotoxic to phagocytic cells; dermonecrotising activity |
| + | |
| + | |
| + | ===Clinical infections=== |
| + | |
| + | *Suppurative infections |
| + | *Abscesses especially in liver |
| + | *Lymphadenitis, [[Bones - inflammatory#Osteomyelitis|osteomyelitis]], peritonitis and neural abscessation |
| + | *Pyometra |
| + | *Endometritis |
| + | *Summer mastitis |
| + | *Ovine foot disease |
| + | *Arthritis |
| + | *Umbilical infections |
| + | *[[Bacterial infections#Acute exudative pneumonia|Acute exudative pneumonia]] and contributes to [[Bacterial infections#Enzootic pneumonia of calves|Enzootic pneumonia of calves]] |
| + | *May cause [[Muscles - inflammatory#Abscesses|myositis]] |
| + | |
| + | |
| + | ===Treatment=== |
| + | |
| + | *Penicillin or broad spectrum antibiotics |
| + | *Unclassified ''Actinomyces'' species isolated from closed cases of [[Bursae and Tendons - inflammatory#Poll Evil and Fistulous Withers|Poll Evil and Fistulous Withers]] |