Effects of acute 2,4-dichlorophenoxyacetic acid on cattle serum components and enzyme activities.

The acute toxicity of 2,4-dichlorophenoxyacetic acid (2,4-D) was studied in cattle. Steers were dosed po with 100, 300 or 600 mg 2,4-D/kg bw. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (AP), O-glutamyl transferase (O-GT), creatine kinase (CK), lactate dehydrogenase (LDH) activities and urea, creatinine, glucose, total proteins and albumin levels were determined at intervals after dosing. The lowest 2,4-D dose did not change the biochemical parameters studied; the 300 mg/kg dose decreased AST, O-GT and CK activities and increased urea and glucose levels; the highest dose of 2,4-D increased LDH and CK activities and protein, urea, creatinine and glucose levels. These changes were time and dose-dependent and completely reversible. Acute 2,4-D intoxication disrupted the serum levels of several enzymes and blood components which mainly reflect kidney and muscle damage induced by the herbicide.