[Monensin poisoning in dairy cattle. Report of a case (author's transl)].

A herd of dairy cattle were fed concentrates in which monensin had been incorporated in error in a concentration of 366 mg/kg. Particularly those animals which were highly productive, showed a marked drop in production within two days after the herd had been fed this lot. The animals were sluggish, did not ruminate, had watery, alkaline rumen contents and failed to ingest anything. When hay was supplied ad lib., the symptoms disappeared within approximately three days.