Hertia pallens

Abstract

DISTRIBUTION: It prefers calcareous soil, sand, loam, shale and white quartzite and can become abundant on degraded grassveld, hillsides, rocky ridges, dry river beds, in low lying areas and along roadsides. Invader on overgrazed veld. Botanical description: General: A weed, growing as a bushy shrub, ±1 m high, with pale papery stems Leaves: The leaves are flat, linear-oblong, alternating Flowers: Golden yellow to orange, solitary flower heads.

TOXIC PRINCIPLE: Unknown hepatoxin, but also pneumotoxic in sheep.

SYNDROMES: Hepatotoxic syndrome without photosensitization.

SYSTEMS AFFECTED: Liver and respiratory system.

CLINICAL SIGNS: • Sheep problem • Peracute - die during night - acute liver failure Liver syndrome: • Icterus • Restlessness • Do not eat • Ruminal stasis, bloat • Lag behind and refuse to walk Lung syndrome: • Dyspnoea, cyanosis • Difficult expiration. • Alveoli burst and air escapes into interstitial tissue, migrate to bronchi and trachea until under the skin where it causes swelling and crepitation - “lugdikkop”.

NECROPSY: Macroscopical findings: • Generalized oedema and ascites • Emphysema• Icterus• Pronounced degeneration, especially liver and kidneys. • Pale grey-yellow liver.

HISTOPATHOLOGY: • Diffuse hepatocellular degeneration and necrosis • Lung oedema and emphysema. • Interstitial pneumonia.