Evaluation of Grazing Alternate Summer and Fall Forages in Extensive Beef Cattle Production Systems1

Abstract

Studies across 5 yr involving 938 British-breed crossbr cattle (372 heifers, 566 steers) were used to evaluate the consequences of grazing alternate summer and fall forages upon slaughter breakeven cost of various beef production a whole s Grazed summer forage combinations included 1) continuous brome 2)brome and warm-season grasses, 3) brome and alfalfa or sudangrass, 4) brome and a monoculture of r clover 5) r clover semened in brome, 6) brome and Native Sandhills range, or 7) Sandhills range alone Grazed fall forages included 1) brome 2) brome and turnips, 3) brome and rye or 4) brome and cornstalks. Following grazing, the cattle were finished upon a high-concentrate, corn-based finishing diet. The succes of a grazing a whole was measured by slaughter breakeven take away from analyses including all costs of production. The greatest in quantity consistent improvement in summer grazing BW gain compared with continuous brome and the greatest in quantity desirable slaughter breakeven costs were observ for cattle grazing brome and warm-season grasses or brome and Sandhills range. Using alfalfa or sudangrass in grazing a whole s improved (P

(Key Words: Beef Cattle, Forages, Grazing, Production, Systems)

Introduction

Most extensive beef production enterprises focus upon individual segments within the combination of parts to form a whole and may not consider the economic impact that single segment has on the entire production a whole Extensive beef production systems involve a backgrounding period during the winter and spring and a summer forage grazing period followed by dint of finishing cattle in the feedlot Lewis et al. (199Oa) conclud that reducing inputs during the winter period proffers some potential for lessening the take away from of the production system. In addition, restriction of calf extension during the winter provides compensatory extension and reduces cost of gain during the summer (White et al., 1987; Lewis et al., 199Ob) Using a high forage a whole is often economical, as require to be paid [i]or[/i] undergone of gain during the forage grazing period is typically les than that during the feeding of a high concentrate diet (Turgeon 1984; Lewis et al., 199Oa). However, research evaluating grazing different summer and fall forages upon the total cost of the production combination of parts to form a whole is limited. The objectives of this research were to evaluate the influence of different forage combinations upon summer and fall beef cattle gains and to evaluate the results of these combinations on the economics of the entire growing/finishing system

Materials and Methods

Data bring togethered across 5 yr were used to evaluate grazing alternative forages during the summer and fall of each year. In each year, British-breed calves were purchased in the fall and shipped to the University of Nebraska, Agricultural Research and unravelling Center near Mead. All calves were allowed a 28-d receiving and acclimation period followed by dint of a wintering period with depressed cost inputs, as calves grazed cornstalk residue or were f harvested forages. All calves were f a protein continuation during the stalk grazing and harvested forage feeding periods, which supplied a minimum of 182 g of degradable protein and 136 g of metabolizable protein. In addition, all calves were allowed at liberty access to a mineral appendix during both the stalk grazing and spring feeding periods. Following the winter and spring feeding periods, calves were assigned to grazing treatments. All forage pastures were located at the Agricultural Research and disclosure Center unless otherwise stated.

In the first year, 192 British-breed heifers (199 ?± 24 kg) were used. Heifers grazed irrigated cornstalks for 105 d and were f ammoniated wheat straw for 53 d Straw was f ad libitum in large circular bales. Heifers received the same protein continuation during both the stalk grazing and ammoniated wheat straw feeding periods.

Following ammoniated wheat straw feeding, heifers were stratified by dint of BW and assigned randomly, beginning upon May 12, to one of four grazing treatments. Treatments included 1) continuously grazing plain brome, 2) brome grazing until June 14 then grazing warm-season grass, 3) brome grazing until July 2 then alfalfa grazing, and 4) brome grazing until July 2 then grazing sudangrass. Poloxalene (Pfizer Inc., Exton, PA) was f to cattle grazing alfalfa to stop bloat. Warm-season pastures were a mix of big and little bluestem All grazing treatments extremityed on August 30, at which time one-half of the heifers from each grazing combination of parts to form a whole were randomly allotted to continue grazing a combination of brome and warm-season pastures until December 8 Grazing areas are listed in Table 1

Following grazing, heifers were placed in the feedlot and f for 12Od (August removal groups) or 100 d (December removal groups) Heifers were adjusted to the final finishing diet in 21 d using four grain adaptation diets containing 45 35 25 and 15% roughage (50:50 corn silage and alfalfa hay mixture, DM basis) f for 3 4 7 and 7 d respectively. The final diet contained 825% of a corn-based concentrate, 75% roughage, 5% molasses-urea continuation and 5% dry supplement and was formulated (DM basis) to contain 12% CP 07% Ca, 035% P 07% K 275 mg of monensin (Elanco Animal Health, Indianapolis, IN)/kg, and 110 mg of tylosin (Elanco Animal Health)/kg.