By Whitney Rounds, Ph.D.
Senior Technical Services Manager at Kemin Industries
In today’s market, beef cattle fed under commercial feeding practices are subject to multiple stresses, all potentially detracting from maximizing red meat production at the lowest possible cost.
At weaning, beef calves separated from dams, marketed through typical feeder cattle channels, involving auctions, order-buyer barns, sorting and often long haul transport generally respond negatively to exposure of pathogens and unfamiliar environments. At the feedlot, feeder cattle are further challenged with new feed and water sources, rapid ration changes and feedlot processing. During the feeding period, beef cattle are further challenged with high concentrate diets with minimal roughage levels, fortified with growth implants and feed additives to maximize lean tissue accretion. With the addition of beta agonists, further metabolic stress is imposed at the end of the feeding period. Feeder cattle that successfully negotiate this process are often those provided adequate nutrition including trace minerals.
Maximizing the genetic potential of high performance cattle demands an increase in energy efficiency. Enhancing glucose uptake increases the opportunity to maximize performance and increase profits. Chromium (Cr) plays a significant role in this process providing an increase in glucose to the animal at the cellular level.
Chromium Propionate is a highly bioavailable source of chromium for use in cattle feeds1. Chromium Propionate allows cattle to utilize energy more efficiently. The primary role of chromium is to potentiate the action of insulin. Increased insulin activity promotes intracellular glucose uptake, providing more efficient energy utilization.
Research conducted by Dr. Brad Johnson and Bryan Bernhard at Texas Tech University was presented at the ASAS2 meetings in New Orleans in July 2011. One hundred eighty (180) steers were selected for use in the study, blocked by weight and randomly assigned to pens. The study was a completely randomized block design, (36 pens; 9 pens/treatments; 4 pens/block; 5 steers/pen). Cattle were housed in dirt-lot pens with ad-libitum access to sudangrass hay upon arrival. The following morning, a 63% concentrate basal ration was fed on top of the sudangrass hay. Cattle were processed upon arrival. Cattle were fed once daily in the morning. Cattle were fed the 63% concentrate diet from days 0 to 14, then increased at day 14 and day 28 to 73% and 83% concentrate diets, respectfully. The 83% concentrate diet was fed for the remainder of the trial. Cr was supplied in the form of KemTRACE®brand Chromium Propionate 0.04%. Premixes were top dressed and hand mixed into the delivered daily ration. Cattle health was evaluated daily for clinical signs of illness. Rectal temperatures were taken on cattle pulled. Cattle with temperatures > 39.7ºC were treated and returned to their home pen.
Researchers reported that steers fed chromium propionate showed a linear increase in average daily gain (P<0.03) and feed efficiency (P<0.05) as chromium propionate concentrations increased, with an increase of 10.8% and 4.2%, respectfully (when comparing the control and 0.3 mg/kg) (Figures 1 and 2). In Figure 3, steers fed chromium propionate displayed a tendency to increase their dry matter intake (DMI) (P = 0.12) linearly as the level of chromium propionate was increased. The morbidity data showed results with a tendency (P = 0.07) for a linear decrease in the number of cattle treated at least once for respiratory symptoms as the chromium propionate concentration increased. Numerically 12.5% less cattle were treated at least once for respiratory symptoms in the 0.3 mg/kg treatment group versus other treatment groups.
This study was initiated to gain additional insight into feeding KemTRACE® brand Chromium Propionate to feeder cattle typical of the U.S. commercial cattle feeding business segment. Results of this study suggest that supplementation of chromium propionate to the basal diet can have a beneficial effect on newly received steers. More specifically in the research reported by Bernhard et al. (2011), addition of 0.3 mg/kg of chromium propionate to the basal diet resulted in the strongest performance advantages and reductions in the incidences of morbidity over the entire trial period. When comparing cattle supplemented with 0.3 mg/kg of chromium propionate to control cattle, there was an 8 kg difference in final BW and over 18% fewer cattle were treated at least once in this study. This translates to selling more pounds of beef, with less treatment cost2.