Chrysocoma ciliata

Abstract

DISTRIBUTION: It is widely distributed in the Karoo on a variety of soil types, ecxept in brackish areas, where it does not flourish.

BOTANICAL DESCRIPTION: General: A soft, dense, perennial woody shrublet about 100 - 600 mm high with a rounded form, 60 - 400 mm in diameter. It is an extremely active invader, which flourishes on overgrazed veld. Leaves: The numerous hairless leaves are small, narrowly linear, somewhat sticky and arranged alternately on the stems. They taste bitter, hence the common name. Flowers: At the end of almost every branchlet there is a small yellow flower head. It is ±10 mm in diameter and without ray florets.

TOXIC PRINCIPLE: Valsiekte • An unidentified toxin Kaalsiekte • Nursing lambs/kids: An unidentified toxin is excreted in the milk of ewes and affects the suckling lamb/kid. Lakseersiekte • Sheep or cattle which ingest large amounts of bitterbush develop diarrhoea.

SYNDROMES: Valsiekte, Kaalsiekte, Lakseersiekte.

SYSTEMS AFFECTED: Central nervous and gastro-intestinal systems, as well as skin and appendages.

CLINICAL SIGNS: • Dorpers and Dorper-crosses are susceptible to Valsiekte. (Merino’s don’t eat the plant). • 2 - 4 month old lambs are affected. • Ataxia of hindquarters, paresis. • Diarrhoea and alopecia simultaneously contracted. Kaalsiekte is a problem in sheep lambs and goat kids less than 3 weeks of age when the mothers graze on the bitter bush and ingest large amounts, usually unpalatable. • Problem seen after good rains if the bitter bush is plentiful, young and succulent. • Lamb/kid is born with a normal coat. • The toxin is excreted in milk. • From 3 - 14 days old (after 3 weeks not a problem anymore) pruritus, the pulling out of fleece or hair and alopecia (especially over the rump, shoulders and trunk) are noticed. • Usually only the non-pigmented parts are affected. • Wool/hair remains on the limbs and head. • Complications: - Exposure - sun burnt during the hot, sunny days. - Evenings very cold - hypothermia, pneumonia. Sheep and cattle suffering from Lakseersiekte may die suddenly or develop a persistent, sometimes haemorrhagic diarrhoea, which leads to weakness, dehydration and recumbency.

NECROPSY: Valsiekte: • Status spongiosus of spinal cord Lakseersiekte: • Severe gastroenteritis - even haemorrhagic. • Ulcerative lesions.

TREATMENT: Valsiekte: • No specific treatment Kaalsiekte: • Protect against the sun during the day and extreme cold during night. • Lanolin and other emollients on the skin. Lakseersiekte: • Remove immediately and treat symptomatically.• Sheep: Fluid and electrolyte replacement.