Disturbances of calciumhomeostasishave beenassociatedwithavarietyofdisease conditions inanimals.Knowledge of serumtotal calciumvalues is essential for understanding disease states that cause calciumalterations outside the reference range. Variations in albumin values can affect the proportion of protein-bound calciumin the total calcium concentration.Adjustment formulas ofmeasured calciumbased onmeasuredalbumin or total protein concentrations were proposed byMeuten et al (MeutenDJ, ChewDJ, CapenCCandKocibaGJ. 1982. Am. Vet.Med. Assoc. 180, 63- 67): adjustedcalcium=calcium albumin+3.5 or adjustedcalcium=calcium 0.4 xprotein+3.3. This studywas aimed todevelop relationships between serumtotal calciumandalbumin andbetween serumtotal calciumandtotal protein atdifferent clinical settings, andtocompare these relationshipswithMeuten's. Eachequationvarieddependingonthe laboratories, andtherewas aignificant difference in regression slopes between laboratories. The prevalence of calcium disturbance based on the albumin and total protein equation ranging 0.7-12.1%and 4.6 -19.3%, respectively. These findings suggest that adjustingcalciumformulasmust bedevelopedseparatelyat different clinical settings. Bytheuse of their own formulas, it becomes possible to interpret abnormal calcium values correctly in patients with various clinical conditions.