The association between ionized calcium in blood and selected parameters in dairy cows with left displaced abomasum.

The objective of this study was to examine the association between blood calcium (Ca) and left displaced abomasum (LDA), and between Ca and selected anamnestic, blood and urine parameters in cows diagnosed with LDA. One hundred and forty-four cows diagnosed with LDA and 20 controls were used. The association between Ca and LDA was evaluated using linear regression. Possible associations between anamnestic, blood and urine parameters and blood calcium were assessed using a forward stepwise procedure in linear regression. Ca was not significantly associated with LDA. In control cows, Ca was explained by urea alone (R2 = 0.6); this was a negative association. In cows diagnosed with LDA, the final model of Ca included base excess (partial R2 = 0.31), urea (partial R2 = 0.11), phosphorus (partial R2 = 0.03) and potassium (partial R2 = 0.03). A negative linear association was found between base excess and Ca. A quadratic association was found between urea and Ca. We conclude that Ca is significantly associated with urea in dairy cows. Ca is not significantly associated with displaced abomasum in cows diagnosed with LDA. Blood base excess and urea explain Ca in cows diagnosed with LDA.