title: Suspected herbicide toxicosis in a dog.
abstract: An 8-year-old 38-kg spayed female Golden Retriever was admitted for vomiting, signs of abdominal pain on palpation, ataxia, anorexia, and generalized weakness of 2 days' duration. Ten hours prior to onset of clinical signs, the dog was found standing in and drinking from large pools of an accidentally spilled herbicide that contained an octanoic acid ester of bromoxynil (3,5-dibromo-4-hydroxybenzonitrile) and an isooctyl ester of (2-methyl-4-chloro) phenoxyacetic acid (MCPA). Appendicular muscles were firm on palpation and persistent muscle contraction (myotonia > 1 minute duration) was found on muscle percussion, using a reflex hammer. Electrical activity indicative of myotonia was identified on electromyographic evaluation. With supportive treatment, the dog eventually recovered from suspected MCPA toxicosis. Although rare, MCPA toxicosis should be considered as a cause of acquired myotonia in dogs.
authors.affiliation: Department of Clinical Sciences, Washington State University, College of Veterinary Medicine, Pullman 99164-6610, USA.
authors.forename: M L
authors.initials: ML
authors.lastname: Harrington
authors.forename: M P
authors.initials: MP
authors.lastname: Moore
authors.forename: P A
authors.initials: PA
authors.lastname: Talcott
authors.forename: R S
authors.initials: RS
authors.lastname: Bagley
authors.forename: P
authors.initials: P
authors.lastname: Sandmeier
mesh_terms: D008456:2-Methyl-4-chlorophenoxyacetic Acid / Q000506:poisoning*; D015746:Abdominal Pain / Q000662:veterinary; D000818:Animals; D000855:Anorexia / Q000662:veterinary; D000931:Antidotes / Q000627:therapeutic use; D000932:Antiemetics / Q000627:therapeutic use; D001259:Ataxia / Q000662:veterinary; D001803:Blood Transfusion / Q000662:veterinary; D002606:Charcoal / Q000627:therapeutic use; D003131:Combined Modality Therapy / Q000662:veterinary; D003975:Diazepam / Q000627:therapeutic use; D004283:Dog Diseases / Q000139:chemically induced* / Q000503:physiopathology / Q000628:therapy; D004285:Dogs; D004576:Electromyography / Q000662:veterinary; D004733:Enema / Q000662:veterinary; D005260:Female; D005440:Fluid Therapy / Q000662:veterinary; D006471:Gastrointestinal Hemorrhage / Q000139:chemically induced / Q000628:therapy / Q000662:veterinary; D006540:Herbicides / Q000506:poisoning*; D008787:Metoclopramide / Q000627:therapeutic use; D009125:Muscle Relaxants, Central / Q000627:therapeutic use; D009222:Myotonia / Q000139:chemically induced / Q000628:therapy / Q000662:veterinary*; D011041:Poisoning / Q000503:physiopathology / Q000628:therapy / Q000662:veterinary; D012008:Recurrence; D014839:Vomiting / Q000662:veterinary
chemical_list: D000931:Antidotes; D000932:Antiemetics; D006540:Herbicides; D009125:Muscle Relaxants, Central; D002606:Charcoal; D008456:2-Methyl-4-chlorophenoxyacetic Acid; D008787:Metoclopramide; D003975:Diazepam