DISTRIBUTION:
To be found all over the country; next to roadsides, or other areas where the soil has been disturbed.
BOTANICAL DESCRIPTION:
General: These are pioneer plants, which are often mistaken for thistles.
Leaves: The rough serrated blue leaves (A.ochroleuca) or grey-green leaves (A. mexicana) are full of prickles. Yellow latex is produced when the plants are cut.
Flowers: The flowers resemble those of true poppies. Those of A. mexicana are bright yellow, while the flowers of A. ochroleuca are mainly cream-coloured.
Fruit: The fruits are capsule-like and spiny and the seeds are black with indentations (like a hand grenade).
TOXIC PRINCIPLE:
Isoquinoline alkaloids:
1. Berberine • Intense yellow, bitter alkaloid.
• Eventually leads to respiratory depression and paralysis
2. Protopine • Cardiovascular suppression
3. Sanguinarine (predominantly in seed)
• Causes dilation of capillaries and increased permeability
SYSTEMS AFFECTED:
Cardiovascular and respiratory systems.
CLINICAL SIGNS:
Cattle: Subcutaneous oedema, ascites
Sheep: Lung emphysema (berberine effect)
Chickens: Blue combs, ascites and subcutaneous oedema.
