Effects of Sources and Amounts of Potassium on Feed Palatability and on Potassium Toxicity in Dairy Calves

Abstract

The palatability of four sources and four percents of potassium was determined in Holstein bull calves in 16 cafeteria-designed experiments. Sources included potassium chloride, potassium acetate, potassium carbonate, and potassium bicarbonate. Amounts fed were .77% potassium (control diet) or the control diet plus 2, 4, or 6% potassium from the various sources. Groups of five or six calves were offered a choice of only two test diets for 3 to 7 days in each cafeteria experiment. Feeds supplemented with 2, 4, or 6% potassium as potassium chloride, and 2 or 4% potassium as potassium acetate, potassium carbonate, and potassium bicarbonate were consistently less palatable than the control diet. Palatability decreased with increased dietary amounts of potassium. Potassium chloride-supplemented feeds were more palatable than those supplemented with potassium carbonate but less palatable than those supplemented with potassium bicarbonate or potassium acetate. In a choice between two diets containing different sources or amounts of potassium, calves independently choose one diet over the other according to the source or amounts of potassium in the diets. Thus, the intake of one diet is relative to the intake of the other when two are offered simultaneously. Where calves were offered only one diet containing 2% supplemental potassium as potassium chloride, voluntary feed intake or growth were not affected adversely. However, 6% added potassium decreased voluntary feed intake and weight gains. The maximum dietary potassium which produced no clinical effect was between 2.8 and 7%. © 1980, American Dairy Science Association. All rights reserved.