Validation of diagnostic tests for determination of magnesium status in horses with reduced magnesium intake

Abstract

Objective - To evaluate the diagnostic value of serum concentrations of total magnesium (tMg) and ionized magnesium (iMg), concentrations of magnesium (Mg) in muscle, intracellular Mg (icMg) concentrations, urinary Mg excretion (EMg), Mg clearance (C Mg), and fractional clearance of Mg (FCMg) in horses fed diets with Mg content above and below National Research Council recommendations. Animals - 9 young female horses. Procedures - 6 horses were fed a reduced-Mg diet for 29 days followed by an Mg-supplemented diet for 24 days. Control horses (n = 3) were fed grass hay exclusively. Blood, urine, and tissue samples were collected, and an Mg retention test was performed before and after restrict..