Metabolic Effects of Dietary Chromium-L-Methionine in Horses and Beef Cattle

A series of three studies was conducted to determine the metabolic effects of Cr from chromium-L-methionine (CrMet) on glucose metabolism in horses and beef cattle. In Study 1, 28 stock-type horses were used in a completely randomized block design to determine the effect supplemental dietary CrMet on glucose tolerance (Intravenous Glucose Tolerance Test, IVGTT) and insulin sensitivity (Intravenous Insulin Challenge Test, IVICT). Supplemental Cr was fed at a rate to supply 0, 0.005, 0.01 or 0.02mgCr/kg body weight (BW). There were significant linear and quadratic effects (P 20yrs of age were used in two separate trials (n = 12 mares/trial) to determine if CrMet would affect glucose (GLU) and insulin (INS) responses in aged horses, The mares were individually fed alfalfa/whole corn plant cubes and pelleted concentrate (ES: Equine Senior, Purina Mills, Inc) in two daily feedings, with 1.36kg ES and 1⁄2 of the cubes offered at 0800h, the rest given at l,600h. The CrMet was incorporated into an alfalfa based pellet and fed daily (l,600h) to provide: 0mg (Control), 0.01 mg (Trt 1) or 0.02mgCr/kg BW (Trt2). Mares were randomly assigned to treatment groups, blocked according to their insulin responses to pre-supplementation intravenous dextrose challenge (IVGTT). Mares with insulin responses >250 IU/mL were