Determination of Strong Ion Difference and Anion Gap from blood biochemical parameters in Lactating Cow

Abstract

The objectives of this study are to determine serum strong ion differences (SID) and anion gap (AG) of 8 high yielding lactating dairy cows with a history of inappetence and drop of milk production. Blood biochemical data of 8 cows were collected from diagnostic reports done at the Department of Physiology, Biochemistry and Pharmacology, Chattogram Veterinary and Animal Sciences University. Concentrations of quantitatively important strong ions (Na+, K+, Ca2+, Mg2+, Cl-) and nonvolatile buffer ions (total protein and phosphate) were determined and a fixed L-lactate value was used. Mean (±SD) of Strong ion difference (SID) was determined by calculating the differences between measured strong anion and cation concentrations (SID3, 37.56 mEq/L; SID4, 37.02 mEq/L; SID6, 40.14 mEq/L). Mean value of Atot, total plasma concentration of nonvolatile weak acids was calculated (Atot, 28.10 mmol/L) and this value along with a fixed value of Ka, effective dissociation constant for plasma weak acids and pH is then used to calculate concentrations of HCO3-. Anion Gap is then determined and the mean value of anion gap (AG) is 16.62 mEq/L, which is within the normal reference range. Although acid-base abnormalities are frequently present in sick animals. Measuring SID and AG will not only help in explaining the underlaying disease mechanisms of Acid-base disorders but also will help in proper treatment protocols.