Feedlot performance, feed efficiency, and profitability of cattle fed either a complete mixed ration or allowed to voluntarily select their diet.

Cattle in feedlots are typically fed a total mixed ration (TMR). However, feeding a TMR may lead to lower feed efficiency, reduced gains, and increased stress when compared to offering cattle a choice of feeds in the TMR. We determined how cattle offered a choice of foods or a mixed ration of those same foods would affect the performance and profitability of cattle. In year 1, heifers were fed a mixed ration (70% corn, 19.2% alfalfa pellets, and 10.8% haylage) or free choice of the three foods. Cattle given a choice of foods ate 69% corn, 26.9%, alfalfa pellets, and 4.1% haylage. No differences were detected in intake, gain, feed efficiency, or cost of gain. In year 2, heifers were fed a mixed ration (60% corn and 40% chopped alfalfa hay) or a choice of corn and hay. Heifers offered a choice of feeds ate 74.3% corn and 25.7% alfalfa hay. Cattle given a choice of foods ate less feed but gained at the same rate as those fed the mixed ration. Feed to gain ratio and total intake were lower for choice than mixed. Cost per pound of gain was similar for the two groups of heifers. Offering animals a choice of feeds may be a viable way for producers to finish their cattle because offering a choice of feeds compared to a mixed ration: 1) eliminates the need to mix feed and for a nutritionist to balance the ration; 2) animals of different sizes and ages can be fed together; 3) gives producers flexibility when marketing their animals; 4) may improve feed efficiency and cost of gain while decreasing stress and illness.

Introduction

Finishing cattle prior to slaughter typically entails feeding total mixed rations (TMR) nutritionally balanced for a group of cattle. Group feeding a TMR is thought to be the best method to feed animals concentrate rations. Under a TMR feeding system the ration is balanced for the nutritional needs of the average animal. Unfortunately, this practice doesn’t consider importance of individual variation in need for nutrients. Past research shows that as many as half of the animals within a group may have different nutritional needs or tolerances when compared to the “average” animal (Provenza et al., 1996; Villalba and Provenza, 1996; Scott and Provenza, 1999). Thus, feeding a TMR may negatively affect the productivity of some animals fed a TMR formulated to meet the needs of the “average” animal.

Offering livestock a choice of foods likely allows them to select a diet that meets their individual needs. Choice also provides animals with variety. Animals prefer variety to monotony. Herbivores often select a variety of foods that vary in nutrients, even though one food seems to best meet their needs. Lastly, offering animals a choice of foods reduces their stress.

Numerous studies have shown that providing animals a choice of foods can increase intake, improve feed efficiency, and decrease costs compared to feeding a TMR. However, only one study on offering cattle feed choice has been conducted in the U.S. Most studies on feed choice have been conducted on sheep or goats outside the U.S.

This project tested if allowing cattle to voluntarily select feeds that differ in nutritional value will improve livestock performance. Growing heifers were assigned to two groups and fed a 1) TMR or 2) choice of feeds. They were fed in a GrowSafe feed system that measures individual animal intake via RFID ear tags. Heifers were to be evaluated for weight gain and individual feed intake during the test period. Daily gain, feed efficiency, and residual feed intake (RFI) were to be individually calculated to determine if feeding method will improve performance and feed conversion. Profitability of the two feeding systems were to be compared by contrasting feed costs, including costs associated with diet formulation, equipment, labor, gains achieved, feed efficiencies, and net income received.