Acute toxicosis in cattle sprayed with endosulfan.

Two cattle died acutely after being sprayed for lice control with a cyclodiene organochlorine insecticide, endosulfan, not labelled for use in cattle. Three other cattle became acutely ill, but survived after symptomatic therapy and removal of the insecticide from their skin and prevention of enterohepatic circulation. These cases illustrated the risk of acute toxicosis when organochlorine insecticides are used off-label and the potential for illegal tissue and milk residues.