title: Effects of xylazine, romifidine, or detomidine on hematology, biochemistry, and splenic thickness in healthy horses.
abstract: Alpha-2 agonist-induced changes in packed cell volume (PCV), total solids (TS), selected biochemical parameters, and splenic thickness were investigated in horses. Four healthy mares were treated in a blinded, randomized, cross-over design with a dose of xylazine (0.5 mg/kg), romifidine (0.04 mg/kg), or detomidine (0.01 mg/kg) IV, and detomidine (0.02 mg/kg) IM. Hematology, TS, colloid osmotic pressure (COP), plasma osmolality; glucose, lactate, urea (BUN) and electrolyte concentrations; venous blood pH and ultrasonographic splenic thickness were evaluated at intervals for 300 min. Repeated measures analysis of variance (ANOVA) were performed with P < 0.05. There was a significant change over time in PCV and TS following each treatment (P < 0.001), with median (range) reductions of 20.9% (12.9% to 27.3%) and 5.8% (3.0% to 10.3%), respectively. Red blood cell count, BUN, and COP decreased while osmolality, glucose, Na(+), and splenic thickness increased. Treatments induced clinically significant transient changes in PCV, TS, and other biochemical parameters, which should be considered when assessing horses that received these drugs.
authors.affiliation: Department of Companion Animal Clinical Studies (Kullmann, Sanz, Saulez, Page, Rioja) and Department of Production Animal Studies (Fosgate), University of Pretoria, Onderstepoort, South Africa.
authors.forename: Annie
authors.initials: A
authors.lastname: Kullmann
authors.affiliation: Department of Companion Animal Clinical Studies (Kullmann, Sanz, Saulez, Page, Rioja) and Department of Production Animal Studies (Fosgate), University of Pretoria, Onderstepoort, South Africa.
authors.forename: Macarena
authors.initials: M
authors.lastname: Sanz
authors.affiliation: Department of Companion Animal Clinical Studies (Kullmann, Sanz, Saulez, Page, Rioja) and Department of Production Animal Studies (Fosgate), University of Pretoria, Onderstepoort, South Africa.
authors.forename: Geoffrey T
authors.initials: GT
authors.lastname: Fosgate
authors.affiliation: Department of Companion Animal Clinical Studies (Kullmann, Sanz, Saulez, Page, Rioja) and Department of Production Animal Studies (Fosgate), University of Pretoria, Onderstepoort, South Africa.
authors.forename: Montague N
authors.initials: MN
authors.lastname: Saulez
authors.affiliation: Department of Companion Animal Clinical Studies (Kullmann, Sanz, Saulez, Page, Rioja) and Department of Production Animal Studies (Fosgate), University of Pretoria, Onderstepoort, South Africa.
authors.forename: Patrick C
authors.initials: PC
authors.lastname: Page
authors.affiliation: Department of Companion Animal Clinical Studies (Kullmann, Sanz, Saulez, Page, Rioja) and Department of Production Animal Studies (Fosgate), University of Pretoria, Onderstepoort, South Africa.
authors.forename: Eva
authors.initials: E
authors.lastname: Rioja
mesh_terms: D058647:Adrenergic alpha-2 Receptor Agonists / Q000009:adverse effects / Q000494:pharmacology*; D000818:Animals; D001786:Blood Glucose / Q000187:drug effects; D001806:Blood Urea Nitrogen; D004906:Erythrocyte Count / Q000662:veterinary; D005260:Female; D006736:Horses / Q000097:blood*; D007093:Imidazoles / Q000009:adverse effects / Q000494:pharmacology*; D009994:Osmolar Concentration; D009997:Osmotic Pressure; D012964:Sodium / Q000097:blood; D013154:Spleen / Q000187:drug effects*; D014991:Xylazine / Q000009:adverse effects / Q000494:pharmacology*
chemical_list: D058647:Adrenergic alpha-2 Receptor Agonists; D001786:Blood Glucose; D007093:Imidazoles; D014991:Xylazine; C041255:detomidine; C076257:romifidine; D012964:Sodium