Interactive effects of dietary sodium and chloride on the incidence of spontaneous cardiomyopathy (round heart) in turkeys

Two pen trials were conducted in Utah, altitude 1,630 m, with Large White f emale turkey poults to evaluate effects of dietary Na and chloride (Cl) con centrations on live performance and deaths caused by spontaneous cardiomyop athy (STC, "round heart") from 0 to 35 d of age. A randomized block 2 x 2 f actorial arrangement with four replicate pens per treatment was used. Pen s ize was 3.8 x 5.6 m. In each trial, four starter diets were formulated from a common basal diet (corn-soy-meat) to obtain the following sodium and chl oride concentrations: High Na (0.24%):High Cl (0.40%); High Na (0.24%):Low Cl (0.16%); Low Na (0.14%):High Cl (0.40%); and Low Na (0.14%):Low Cl (0.16 %). Supplements were NaCl, NaHCO3, NH4Cl, or combinations. After laboratory analysis, true values of Na were slightly lower than expected, Cl was near expected values to slightly low, and K was 1.145%. Body weight and feed conversion ratio at 35 d of age were unaffected in bot h trials. In both experiments, STC mortality was significantly reduced by t he Low Na:High Cl treatment compared to the other treatments. In conclusion , a diet containing 0.10 to 0.12% Na and 0.38 to 0.40% Cl, significantly im proved poult livability by reducing STC mortality without adverse effects o n poult weight or feed conversion ratio.