title: Comparison of platelet counting technologies in equine platelet concentrates.
abstract: OBJECTIVE
  (1) To compare the performance of 4 platelet counting technologies in equine platelet concentrates and (2) to evaluate the ability of the Magellan platelet rich plasma (PRP) system to concentrate equine platelets.
  
  
  METHODS
  Experimental study to assess method agreement.
  
  
  METHODS
  Adult mixed breed horses (n = 32).
  
  
  METHODS
  Acid citrate dextrose-A anti-coagulated whole blood was collected and PRP produced using the Magellan system according to the manufacturer's instructions. Platelets were quantified using 4 counting methods: optical scatter (Advia 2120), impedance (CellDyn 3700), hand counting, and fluorescent antibody flow cytometry. Platelet concentrations were compared using Passing and Bablok regression analyses and mixed model ANOVA. Significance was set at P < .05.
  
  
  RESULTS
  Platelet concentrations measured in identical PRP samples were consistently higher for the Advia 2120 than the CellDyn 3700. Systematic and proportional biases were observed between these 2 automated methods when analyzed by regression analysis of the larger sample size. No bias (systematic or proportional) was observed among any of the other counting methods. Despite the bias detected between the 2 automated systems, there were no significant differences on average among the 4 counting methods evaluated, based on the ANOVA. The Magellan system consistently generated high platelet concentrations as well as higher than expected WBC concentrations.
  
  
  CONCLUSIONS
  The Magellan system delivered desirably high platelet concentrations; however, WBC concentrations may be unacceptably high for some orthopedic applications. All 4 platelet counting methods tested were equivalent on average and therefore suitable for quantifying platelets in equine PRP used for clinical applications.
authors.affiliation: Department of Large Animal Clinical Sciences, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia.
authors.forename: Caitlin M
authors.initials: CM
authors.lastname: O'Shea
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Werre
authors.forename: Linda A
authors.initials: LA
authors.lastname: Dahlgren
mesh_terms: D000818:Animals; D001792:Blood Platelets / Q000502:physiology*; D019343:Citric Acid; D005947:Glucose / Q000031:analogs & derivatives; D006736:Horses / Q000097:blood* / Q000502:physiology; D010976:Platelet Count / Q000295:instrumentation / Q000662:veterinary*; D053657:Platelet-Rich Plasma / Q000166:cytology*; D011237:Predictive Value of Tests; D012044:Regression Analysis
chemical_list: C002113:acid citrate dextrose; D019343:Citric Acid; D005947:Glucose