Interaction of rubidium and potassium in chick diets

Interaction of monensin with dietary vanadium, potassium, and protein, and its effect on hepatic rubidium and potassium in chicks

A series of experiments was undertaken to further investigate the influence of diet composition on chick response to monensin supplementation. Experiments were conducted to determine the effect of monensin on growth rate and hepatic Rb and K content as affected by dietary content of V, K, or protein. A factorial experiment involving V levels of 0, 5, 10, or 20 ppm and monensin levels of 0, 120, or 160 ppm was conducted with broiler chicks to 4 weeks of age. Growth rate was significantly depressed by 10 or 20 ppm V but not by monensin. Hepatic K content was not affected by dietary treatments. In another factorial experiment, effects of levels of 0 and 120 ppm monensin and 0 and 5 ppm V were compared. Growth rate was significantly depressed by both V and monensin but with no significant interaction. Neither hepatic Rb or K content was significantly altered by the supplements. A third factorial experiment involved monensin levels of 0, 120, or 160 ppm, added K levels of 0 or .3%, and dietary protein levels of 16 or 24%. Body weight at 3 weeks of age was significantly depressed by 160 ppm monensin in the high protein diet and by 120 or 160 ppm in the low protein diet. Added K did not counteract the growth depression. Hepatic Rb content was increased by monensin and significantly reduced by K supplementation. Hepatic K content was not increased by K supplementation. Chicks fed the low protein diet had significantly lower concentrations of hepatic Rb and K than those fed the high protein diet.