monensin and potassium-carbonate

The effects of several dietary factors on the anorexigenic response to monensin in chicks fed corn-soybean meal diets varying in crude protein (CP) were investigated. In Trial 1, crossbred chicks (New Hampshire X Columbia) were fed a 16% CP diet with or without 160 mg/kg monensin and/or .53% potassium carbonate in a 2 X 2 factorial design. Monensin supplementation caused a 24.5% growth depression, and potassium carbonate had no effect on the monensin-induced depression. Trials 2 and 3 were designed to evaluate the effects of dietary energy level on the monensin response in commercial broiler chicks fed diets containing 24, 20, or 16% CP. As CP level was decreased, the depression in performance from 121 mg/kg monensin increased. Increasing the energy concentration of the 24 and 20% CP diets to that of the 16% CP diet had no consistent effect on the response of chicks to monensin. Trial 4 was conducted to determine the influence of amino acid (AA) supplementation on the monensin response in broiler chicks fed a low-protein diet. Supplementation of a 16% CP diet with an AA mixture (3% glutamic acid plus essential AA equal to the 24% CP diet) improved growth performance markedly. Deletion of methionine, arginine, and lysine from the AA mixture yielded performance well below that of chicks fed the unsupplemented 16% CP diet, indicating a severe AA imbalance. Monensin supplementation at 121 mg/kg caused a much greater growth depression in chicks fed 16% CP or 16% CP plus the complete AA mixture than in those fed 24% CP or the AA-imbalanced 16% protein diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Amino Acids; Animals; Body Weight; Carbonates; Chickens; Dietary Proteins; Energy Intake; Food, Fortified; Furans; Male; Monensin; Potassium