VERMEERSIEKTE CAUSED BY GEIGERIA-BURKEI HARV. SUBSP BURKEI VAR. HIRTELLA MERXM. IN THE NORTHERN PROVINCE OF SOUTH-AFRICA

The 1st field outbreak of vermeersiekte induced by Geigeria burkei Har v. subsp. burkei var. hirtella Merxm, is reported. It is also the firs t recorded outbreak of this disease in the arid sweet bushveld of the Northern Province of South Africa. The toxicosis was experimentally re produced in a sheep following daily intraruminal administration of 2.5 -5.0 g/kg dried, milled plant material for 18 consecutive days. Neithe r the sheep in the field outbreak nor the ewe in the experiment exhibi ted any signs of regurgitation of rumen contents (vermeersiekte). All developed only the stiff or paretic/paralytic forms of the disease. Se rum activities of CK and GGT were slightly raised in clinically affect ed sheep (n = 11) during the field outbreak, and serum activities of A ST, GLDH, GGT, LDH and CK increased in the ewe dosed with the plant ma terial. Analysis of dried, milled Geigeria plant material confirms tha t this species is moderately nutritious.