Possible effects of anticoagulants on feline plasma biochemical analyses have almost not been investigated. The purpose of the current study was to determine how the most frequently used anticoagulants affect the results of routine biochemistry in feline plasma specimens. Ten clinically healthy cats were blood sampled into tubes containing various types of anticoagulants and plain tubes for harvesting plasma and serum, respectively. The concentrations of glucose, cholesterol, triglyceride, fructosamine, total bilirubin, urea, creatinine, total protein, albumin, calcium, inorganic phosphate, magnesium, iron, sodium, potassium, chloride and the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine kinase (CK) and gamma glutamyl transferase (GGT) were measured with commercial kits and an autoanalyser. Significantly higher concentration of sodium while significantly lower concentration of potassium were seen when heparin was used as an anticoagulant. In sodium citrate plasma most concentrations of metabolites and enzyme activities were lower than in serum due to a specimen dilution and also inhibitory effects. Most analytes differed when EDTA was used as an anticoagulant with the exception of cholesterol, creatinine, CK, GGT, AST, ALT, inorganic phosphate, total protein, urea, and chloride. Heparinized plasma could be used for the measurement of most blood biochemical analytes in cat except for Na and K. Other anticoagulants (EDTA and citrate) cause unfavorable changes in blood biochemical analytes in cats. However, EDTA–plasma could be used for measure concentrations of cholesterol, creatinine, BUN, total protein, and chloride and activities of AST, ALT, GGT, CK.

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