title: Use of operant performance to guide and evaluate medical treatment in an adult male cynomolgus macaque (Macaca fascicularis).
abstract: A 6-y-old male cynomolgus macaque presented with noticeable swelling of the left forearm and signs of discomfort, as indicated by nonuse of the arm even in a behavioral task that he previously had been well-motivated to perform. Examination under anesthesia revealed lacerations to the  arm. Radiography of the forearm showed no fractures, indicating that the damage was limited to soft tissue. The daily operant behavioral session assessed the amount of force the monkey emitted when touching the screen with the affected arm and how long each touch was sustained. We then used  these parameters (force and duration of touch) as objective measures of putative pain relief and recovery of function to guide the medical treatment. The affected monkey received ketoprofen, buprenorphine, or their combination but continued to perform poorly during daily operant behavioral  sessions. Only after treatment with dexamethasone did performance return to preinjury levels, suggesting inflammation near the radial or ulnar nerve. These findings indicate that performance of a trained operant task performance can be useful in guiding medical treatment, evaluating pain relief,  and objectively monitoring health in laboratory animals.
authors.affiliation: Neurobehavioral Toxicology Branch, Analytical Toxicology Division United States Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Aberdeen, Maryland, USA.
authors.forename: Lindsey R
authors.initials: LR
authors.lastname: Hamilton
authors.forename: David M
authors.initials: DM
authors.lastname: Cox
authors.forename: Todd M
authors.initials: TM
authors.lastname: Myers
mesh_terms: D000818:Animals; D003216:Conditioning, Operant; D003907:Dexamethasone / Q000627:therapeutic use*; D005543:Forearm Injuries / Q000188:drug therapy*; D008252:Macaca fascicularis; D008297:Male; D010147:Pain Measurement / Q000379:methods / Q000662:veterinary*; D011597:Psychomotor Performance
chemical_list: D003907:Dexamethasone