DISTRIBUTION:
It grows in damp places, near or even in water, and prefers shady areas.
BOTANICAL DESCRIPTION:
General: An indigenous perennial, herbaceous weed. More or less spreading, but some stems can grow up to a height of 30 to 60 cm. The soft stems are greyish green, but become reddish-purple at times.
Leaves: The simple greyish green leaves are deeply incised.
Flowers: The inflorescence is a daisy-like flower borne on a thin green stalk with white outer flowers and yellow disc-florets. September - April.
Fruit: The seeds are small and oblong.
TOXIC PRINCIPLE:
Unknown neurotoxin – causes encephalitis.
SYSTEMS AFFECTED:
Central nervous system.
CLINICAL SIGNS:
Only a problem with cattle especially in KwaZulu-Natal and the Eastern Cape.
Sheep and horses not susceptible.
• CNS suppression characterized by:
- apathy,
- very tame,
- easy handling,
- aimless wandering and
- apparent blindness
• Incoordination, which can progress to paresis and eventually paralysis.
- Uncertain when walking, knuckling over
• Pushing syndrome
- can only lean against or actively push against firm objects
• Loss of weight (chronic cases) because they don’t eat or drink.
NECROPSY:
Macroscopical findings:
• Nothing obvious.
• Only signs of trauma and weight loss.
HISTOPATHOLOGY:
Encephalitis characterized by perivascular gliosis and lymphocyte infiltration in white matter of the brain and status spongiosus.
DIAGNOSIS:
• Histopathology changes are characteristic
• Typical clinical signs.
TREATMENT:
• None
• Keep the animal away from infected areas in times of food scarcity.
