Effect of Monensin or Salinomycin Supplementation in a 50% Concentrate Diet on Mineral Utilization of Growing Goats

An experiment was conducted to clarify the effects of dietary supplementation of monensin or salinomycin on mineral utilization of growing goats. Six goats weighing 10.54 kg initially were randomly assigned to treatments in a replicated $3{\times}3$ Latin square design. Treatments were a basal diet, basal plus 30 ppm monensin and basal plus 20 ppm salinomycin on a DM basis. The basal diet was a mixture of Italian ryegrass wafer, soybean meal, ground maize and $CaCO_3$ with DM proportions of 50, 13.76, 36 and 0.24%, respectively. Each period lasted for 21 days, and the apparent absorption and retention of minerals were measured during the last 7 days of each period. Salinomycin supplementation improved NDF digestibility and plasma glucose. The apparent absorption and retention of Ca, P, Mg, Na and K were not influenced by the treatments. The concentrations of plasma Ca, P, Mg, Na, K and Cl were similar in all treatments. The ionophore supplementation had no significant effect on acid excretion. The results suggest that 30 ppm monensin or 20 ppm salinomycin supplementation is not effective in improving the utilization of Ca, P, Mg, Na and K in growing goats fed a diet composed of the 50% concentrate.