title: Background variability in standard clinical pathology biomarkers in beagle dogs instrumented with chronic indwelling telemetry devices.
abstract: BACKGROUND
  Contemporary best practice recommendations in preclinical cardiovascular safety assessment promote 3Rs principles. This includes the employment of within-subjects experimental designs to evaluate discrete, acute doses of investigational new drugs, as well as the maintenance of stock colonies of appropriate large animal test systems. Such colony species are often tested repeatedly on independent studies with provision of appropriate recovery periods and requisite health status evaluations (e.g., physical examinations, electrocardiographic assessments, clinical pathology evaluations).
  
  
  METHODS
  To investigate the utility of the often reiterative process of pre- or inter-study clinical pathology testing to help ascertain health status of non-naïve, telemetered canines (beagle dogs), the present study collated the results of a randomly selected set of animals approximately every three months for a period of three years.
  
  
  RESULTS
  Although occasionally a few routine hematology or clinical chemistry endpoints did demonstrate evidence of systematic trending over time, none of the observed fluctuations fell outside the range of expected biological variability, nor would have prevented assignment of any given animal to study.
  
  
  CONCLUSIONS
  The present findings illustrate a high degree of consistency in routinely assessed clinical pathology parameters during the course of chronic telemetry instrumentation in the canine, including relative to historical control data in healthy, experimentally naïve animals of the same species and source, maintained under analogous laboratory conditions. The data suggest that routine assessment of such parameters for the purposes of facilitating judgments concerning suitability for study may represent a pursuit of little overall value, and which may be reasonably accomplished based on alternative, observation-based screening procedures.
authors: Safety Pharmacology, MPI Research, Inc., 54943 North Main St., Mattawan, MI 49071-9399, USA. Electronic address: ted.baird@mpiresearch.com.
authors: Theodore J
authors: TJ
authors: Baird
authors: Clinical Pathology, MPI Research, Inc., 54943 North Main St., Mattawan, MI 49071-9399, USA.
authors: Adam
authors: A
authors: Aulbach
authors: Safety Pharmacology, MPI Research, Inc., 54943 North Main St., Mattawan, MI 49071-9399, USA.
authors: Kyle P
authors: KP
authors: O'Donohue
authors: Safety Pharmacology, MPI Research, Inc., 54943 North Main St., Mattawan, MI 49071-9399, USA.
authors: Joshua D
authors: JD
authors: Yoder
authors: Safety Pharmacology, MPI Research, Inc., 54943 North Main St., Mattawan, MI 49071-9399, USA.
authors: Jill A
authors: JA
authors: Dalton
authors: Safety Pharmacology, MPI Research, Inc., 54943 North Main St., Mattawan, MI 49071-9399, USA.
authors: David V
authors: DV
authors: Gauvin
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D004285:Dogs; D005260:Female; D006304:Health Status; D006403:Hematologic Tests / Q000379:methods; D008297:Male; D023421:Models, Animal; D010338:Pathology, Clinical / Q000379:methods*; D013686:Telemetry / Q000295:instrumentation / Q000379:methods*
chemical_list: D015415:Biomarkers
keywords: Canine; Chronic implantation; Clinical chemistry; Clinical pathology; Hematology; Telemetry