Evaluation of Dietary Roughage Inclusion in a Single or Two-Diet System for Backgrounding and Finishing

Abstract

Study Description: Pre-conditioned crossbred beef steers (n = 46; initial shrunk [4%] BW = 621 ± 89.1 lbs) were used in a 210-d grow-finish experiment at the Ruminant Nutrition Center (RNC) in Brookings, SD. Steers were fed once daily, and bunks were managed according to a slick bunk management system. Cattle were fed in 25 × 25 ft concrete surface pens (n = 10 pens; 5 pens/treatment) with 25 linear ft of bunk space and heated, concrete, continuous flow waterers. Treatments included: 1) A single-diet program (targeted a 59 Mcal/cwt NEg diet fed for 210-d; 1D) or 2) two-diet program (targeted a 55 Mcal/cwt NEg diet fed for 98-d, a 59 Mcal/cwt NEg diet fed for 14-d, and a 63 Mcal/cwt NEg diet fed for 98-d; 2D). All steers were implanted initially (d 1) with a 100 mg trenbolone acetate (TBA) and 14 mg estradiol benzoate (EB) implant (Synovex Choice) and re-implanted with a 200 mg TBA and 28 mg EB implant on d 112