DISTRIBUTION:
Imported plant. Cultivated as pasture in the Western and Eastern Cape and Northern province.
BOTANICAL DESCRIPTION:
General: Grows up to 1 m high. Generally a good fodder, though various toxic syndromes have been associated with it.
Leaves: Compound leaf with a characteristic tendril at the end of the midrib which twines around other plant material.
Flowers: Purple blue pea-like flowers in an erect raceme. Spring - Summer.
Fruit: Small erect pods
TOXIC PRINCIPLE:
Unknown. Unable to reproduce experimentally. Only circumstantial evidence.
SYSTEMS AFFECTED:
Skin and appendages.
CLINICAL SIGNS:
• Problem in cattle.
• Occurs in adult cattle (more than 3 years old).
• Seen in dark breeds (Holstein-Friesians, Aberdeen Angus) which graze for a relative long period (more than 1 month) on green pasture and consume large quantities.
• Latent period 2 - 6 weeks.
• Severe dermatitis and pruritus noticed initially.
• Roughened coats, alopecia.
• Cracks develop in the skin, serum oozes out, crust formation, tissue under crusts are severely inflamed.
• Later, skin becomes unpliable, hard.
• Severe exudative to ulcerative dermatitis.
• Pigmented and non-pigmented skin are affected. (Compare with photosensitivity)
• Mucous membranes affected - conjunctivitis, salivation, mucopurulent nasal discharge.
• Coughing, dyspnoea.
• Severe diarrhoea - even haemorrhagic.
• Drop in condition, emaciation, dehydration, drop in milk production.
• Sick for one week, may take 1 month before they die.
• Older animals more severely affected.
• Up to 35% morbidity and high mortality.
NECROPSY: HISTOPATHOLOGY:
1. Granulomatous lesions in various organs.
- Infiltration of lymphocytes, monocytes and eosinophils in lesion.
- Granulomas in kidney, spleen, liver, myocardium and skin.
2. Skin:
- multifocal,
- ulcerative dermatitis with hyperkeratosis,
- oedema,
- cell infiltration and fibrosis.
TREATMENT:
Antibiotics, fluid and electrolyte replacement, local skin treatment.
