- Fusobacterium necrophorum
- calves and lambs
- common in intensively reared beef cattle
- occurs following an infected umbilicus in neonates and from rumenitis in adult cattle
Gross
- rounded pale multiple foci of coagulative necrosis throughout the liver
- unsoftened, greyish-yellow patches
- ringed by a zone of hyperaemia
- foci coalesce in severe cases
- in adult animals, these lesions may have progressed to abscesses following lysis of the coagulated necrotic tissue and the formation of fibrous capsule around the damaged tissue
- if animal survives, these lesions may soften develop into abscesses
Microscopically
- coagulative necrosis
- possible evidence of migrating flukes
- bacteria can be demonstrated in the periphery of the necrotic tissue, especially near its junction with viable tissue
- there is a rim of neutrophilic cells