The serum concentrations of aspartate amino transferase (AST), alanine amino transferase (ALT). phosphorus. urea and potassium increased in infected animals. The increased AST and ALT levels suggested pathology of the skeletal muscle and hepatic parenchyma due to haemorrhagic gastritis and fatty degeneration of the liver. An increase in the serum phosphorus levels in infected animals may be attributed to a reciprocal relationship with serum calcium and carbohydrate utilization. An increase in urea and potassium concentrations might be due to dehydration and inereased breakdown of proteins, and acidosis as a result of excessive fluid loss and inereased catabolism of fat, protein and carbolhydrate. The serum concentrations of cholesterol, copper, total protein, zinc, calcium, glucose, chloride, iron and magnesium decreased in infected animals. The decrease in the serum concentrations of these substances was attributed to the heavy blood loss and gastro-intestinal disturbances caused by haemonchosis leading to poor absorption and/or metabolism of these nutrients. It is recommended that in addition to an anthelmintic treatment. infected anımals should be provided with essential micro/macro-elements and rehydration salts as supportive therapy.