veterinary: Cattle , Sheep, Goats and Horses : 0.33 gm Tetramisole HCI 10 % per 20 kg b.wt. In a single oral dose given as a drench in water or mixed with fodder

Various enzymes of the tricarboxylic acid cycle (TCA) viz., aconitase (E.C. 4.2.1.3), isocitrate dehydrogenase (E.C. 1.1.1.42), succinate dehydrognease (E.C. 1.3.99.1), fumarate reductase (NADH: fumarate oxido-reductase), fumarase (E.C. 4.2.1.2) and maltate dehydrogenase (E.C. 1.1.1.37) were detected in adult Haemonchus contortus (Nematoda: Trichostrongylidae), in vitro. The effects of D L-tetramisole on various enzymes were studied. At 50 micrograms ml-1 varying degrees of inhibition of succinate dehydrogenase and fumarate reductase activities were observed. At the same concentration, the activities of other enzymes remained unaltered.