RESISTANCE TO DIMINAZINE ACETURATE BY TRYPANOSOMA-CONGOLENSE FROM CATTLE IN THE ZAMBEZI-VALLEY OF ZIMBABWE

The susceptibility of 14 stocks of Trypanosoma congolense, recently is olated from cattle, to therapeutic doses of diminazene aceturate and t o isometamidium chloride was assessed in laboratory mice. Eight isolat es were readily susceptible to the normal therapeutic dose of diminaze ne, two were resistant to the drug at 14 mg kg(-1), and four were tota lly resistant at 28 mg kg(-1). All the isolates were susceptible to is ometamidium chloride at 0.5 mg kg(-1). These observations highlight th e need for regular evaluation of drugs used in the control of trypanos omosis.