181 Evaluation of mixer performance in cattle finishing diets with 15 or 30 percent dry matter basis inclusion of corn silage

Abstract

Abstract Batch fraction (BF), corn silage inclusion level (DIET), and mixing duration (DUR) were evaluated in an experiment using finishing diets based on corn silage and a blend of dry-rolled (DRC) and high-moisture corn (HMC). A 2.35 m3 horizontal mixer was used to manufacture all diets. The experiment was designed as a 5 x 2 x 2 factorial arrangement with nine replications per simple treatment mean. Factors included: 1) BF (n = 5), 2) DIET (n = 2) containing (DM basis) 15% corn silage or 30% corn silage replacing the corn blend, and 3) DUR (n = 2) of 20 or 25 mixer revolutions. Diets contained corn silage, a 1:1 ratio of DRC:HMC, a liquid supplement (5% DM inclusion), and a meal supplement (7% DM inclusion). Data were analyzed as a completely randomized design using the GLIMMIX procedure of SAS 9.4 (SAS Inst., Inc., Cary, NC) using a multinomial approach. The Penn State Particle Separator was used to separate fractions of the total mixed ration (TMR) with special interest on the portion of the TMR retained on the 19 mm sieve. No interactions between BF, DIET, and REV were detected (P ≥ 0.44). There was a 53.5% increase (P = 0.01) in retention on the 19 mm sieve from the first BF (first 20% of the TMR unloaded from the mixer) compared to the last BF (last 20% of the TMR unloaded from the mixer). The LOW diet had 71.3% decrease (P = 0.01) in retention on the 19 mm sieve (2.13 vs. 7.43 ± 0.220%) compared to the HIGH diet. Increasing DUR from 20 to 25 revolutions had no appreciable influence (P = 0.23) on particles greater than 19 mm. These data indicate that BF fed could alter dry matter intake, dietary net energy content, and influence daily gain. Wednesday, July 22, 2020