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First published online December 8, 2023

The Spontaneous Incidence of Neurological Clinical Signs in Preclinical Species Using Cage-side Observations or High-definition Video Monitoring: A Retrospective Analysis

Abstract

When conducting toxicology studies, the interpretation of drug-related neurological clinical signs such as convulsions, myoclonus/myoclonic jerks, tremors, ataxia, and salivation requires an understanding of the spontaneous incidence of those observations in commonly used laboratory animal species. The spontaneous incidence of central nervous system clinical signs in control animals from a single facility using cage-side observations or high definition video monitoring was retrospectively analyzed. Spontaneous convulsions were observed at low incidence in Beagle dogs and Sprague–Dawley rats but were not identified in cynomolgus monkeys and Göttingen minipigs. Spontaneous myoclonic jerks and muscle twitches were observed at low incidence in Beagle dogs, cynomolgus monkeys, and Sprague–Dawley rats but were not seen in Göttingen minipigs. Spontaneous ataxia/incoordination was identified in all species and generally with a higher incidence when using video monitoring. Salivation and tremors were the two most frequent spontaneous clinical signs and both were observed in all species. Data from the current study unveil potential limitations when using control data obtained from a single study for toxicology interpretation related to low incidence neurological clinical signs while providing historical control data from Beagle dogs, cynomolgus monkeys, Sprague–Dawley rats, and Göttingen minipigs.

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Article first published online: December 8, 2023
Issue published: March/April 2024

Keywords

  1. neurological clinical signs
  2. seizure
  3. myoclonus
  4. tremors
  5. salivation
  6. ataxia
  7. muscle twitch
  8. convulsions

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PubMed: 38063479

Authors

Affiliations

Chiara Orciani, PhD
Charles River, Laval, QC, Canada
Cristina Ballesteros, PhD
Charles River, Laval, QC, Canada
Eric Troncy, DMV, MSc, PhD
GREPAQ, Faculté de Médecine Vétérinaire, Universite de Montreal, Saint Hyacinthe, QC, Canada
Clemence Berthome, DVM
Centre Veterinaire DMV, QC, Canada
Kim Bujold, PhD
Charles River, Laval, QC, Canada
Nehla Bennamoune, PhD
Charles River, Laval, QC, Canada
Samantha Sparapani, PhD
Charles River, Laval, QC, Canada
Michael K. Pugsley, DMV, MSc, PhD
Cytokinetics, South San Francisco, CA, United States
Dominique Paquette, DVM
GREPAQ, Faculté de Médecine Vétérinaire, Universite de Montreal, Saint Hyacinthe, QC, Canada
Emmanuel Boulay, DVM
Charles River, Laval, QC, Canada
GREPAQ, Faculté de Médecine Vétérinaire, Universite de Montreal, Saint Hyacinthe, QC, Canada
Simon Authier, DVM, MBA, PhD, DSP
Charles River, Laval, QC, Canada
GREPAQ, Faculté de Médecine Vétérinaire, Universite de Montreal, Saint Hyacinthe, QC, Canada

Notes

Simon Authier, DVM, MBA, PhD, DSP, Charles River, 445 Armand Frappier, Laval, QC H7V 4B3, Canada. Email: [email protected]

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