Platelet counts were performed in 43 Cavalier King Charles Spaniels (CKCS, a breed predisposed to macrothrombocytopenia) and in 10 control dogs using 3 automated systems and 3 manual methods (erythrocyte-lysing agents + counting chamber or evaluation of blood smear). Good correlations were found between platelet counts using all methods (all P < 0.0001; R2 = 0.71–0.85). Best correlations were found between the manual methods. Significantly larger platelets were found in CKCS with platelet count ≤100,000/μl when compared with control dogs and CKCS with platelet count >100,000/μl (both P < 0.0001). All platelet counts—except when made with the 2 counting chamber methods—were underestimated a platelet counts ≤100,000/μl.
References
1.
BlandJMAltmanDG: 1986, Statistical methods for assessing agreement between two methods of clinical measurement. Lancet1:307–310.
2.
BrownSJSimpsonKWBakerS: 1994, Macrothrombocytosis in Cavalier King Charles Spaniels. Vet Rec135:281–283.
3.
DayHJRaoAK: 1986, Evaluation of platelet function. Semin Hematol23:89–101.
4.
EksellPHäggströmJKvartCKarlssonÅ: 1994, Thrombocytopenia in the Cavalier King Charles Spaniels. Vet Rec35:153–155.
5.
GrindemCBBreitschwerdtEBCorbettWT: 1994, Thrombocytopenia associated with neoplasia in dogs. J Vet Intern Med8:400–405.
6.
KarpatkinSKhanQFreedmanM: 1978, Heterogeneity of platelet function. Correlation with platelet volume. Am J Med64:542–546.
MeinkothJHClinkenbeardKD: 2000, Normal hematology of the dog. In: Schalm's veterinary hematology, ed. FeldmanBFZinklJGJainNC, 5th ed., pp. 1057–1063. Lippincott Williams & Wilkens, Maryland, PA.
9.
OlsenLHKristensenATHäggströmJ: 2001, Increased platelet aggregation response in Cavalier King Charles Spaniels with mitral valve prolapse. J Vet Intern Med15:209–216.
10.
PedersenHDHäggströmJOlsenLH: 2002, Idiopathic asymptomatic thrombocytopenia in Cavalier King Charles Spaniels is an autosomal recessive trait. J Vet Intern Med16:169–173.
11.
PermanV: 2002, The blood smear. In: Notes in laboratory medicine, ed. PermanV, pp. 1–24. University of Minnesota, St. Paul, MN.
12.
TvedtenHGrabskiSFrameL: 1988, Estimating platelets and leukocytes on canine blood smears. Vet Clin Pathol17:4–6.
13.
WeiserMG: 1995, Erythrocyte responses and disorders. In: Textbook of veterinary internal medicine, ed. EttingerSJFeldmanEC, pp. 1864–1891. W.B. Saunders Company, Philadelphia, PA.
14.
WynnRFDaviesSVWilliamsKTrevettDG: 1995, The effect of time from venipuncture and choice of anticoagulant on mean platelet volume estimations. Clin Lab Haematol17:173–176.
15.
ZelmanovicDHetheringtonEJ: 1998, Automated analysis of feline platelets in whole blood, including platelet count, mean platelet volume, and activation state. Vet Clin Pathol27:2–9.
