K. C. McCuistion

Nutritive value, fermentation characteristics, and in situ disappearance kinetics of sorghum silage treated with inoculants

Fibrolytic enzymes and microbial inoculants have the potential to improve the value of sorghum feedstuff and feedstock. An experiment was conducted to determine nutritive value, ensiling characteristics, and in situ disappearance kinetics of 4 sorghum (Sorghum bicolor L.) silage varieties: Dairy Master BMR (DBMR; brown midrib; Richardson Seed, Vega, TX), PS 747 (PS; photoperiod sensitive; Pogue Seed, Kenedy, TX), Silo 700D (S700D; conventional forage type; Richardson Seed), and MMR 381/73 (MMR; conventional forage type; Richardson Seed) pretreated with fibrolytic enzyme (xylanase plus cellulase, XC; 50:50 mixture of Cellulase Plus and Xylanase Plus; Dyadic, Juniper, FL) or microbial [Promote ASB (Lactobacillus buchneri and Lactobacillus plantarum); Cargill Animal Nutrition, Indianapolis, IN; PRO] inoculants. The greatest yield was for cultivar PS and the least for MMR. Neutral detergent fiber (NDF) concentration was least for XC-treated silage, and acid detergent fiber (ADF) concentration was least for XC- and PRO-treated silage. When silage was treated with XC, concentrations of NDF concentrations decreased, on average, 4.81% across all cultivars and ADF concentrations decreased, on average, 3.23% in all cultivars except MMR. Inoculant PRO reduced the NDF concentration of DBMR by 6.47%. The ADF concentrations of DBMR and PS treated with PRO were decreased by 3.25%. Treating sorghum silage with XC or PRO reduced the NDF and ADF fractions, which increased cell wall degradability. In vitro true digestibility was greatest for PRO-treated DBMR, whereas acid detergent lignin was least for PRO-treated DBMR. Aerobic stability was not improved by PRO; however, aerobic stability of XC-treated MMR was 63 h greater than that of the control. Acetate concentrations were greatest for XC-treated MMR, which explains the 63-h improvement in aerobic stability due to the inhibition of fungi. However, inoculant PRO did not improve yeast and mold counts or aerobic stability of sorghum silage compared with the control, which may be due to the lesser acetate concentrations, especially of PRO-treated S700D silage. Generally, in situ disappearance kinetics were improved with the application of XC and PRO, and XC had the greatest effect on silage with greater NDF and ADF concentrations.

Evaluating Strategies for Ranching in the 21st Century: Successfully Managing Rangeland for Wildlife and Livestock

Evaluating Strategies for Ranching in the 21st Century: Successfully Managing Rangeland for Wildlife and Livestock DOI:10.2458/azu_rangelands_v30i2_anderson

A Systems Thinking Approach to Ranching: Finding Leverage to Mitigate Drought

On the Ground Drought is an adaptive challenge where management strategies and practices that work today might not work tomorrow. Adaptive challenges facing management may require thinking systemically to determine leverage points. Systems thinking can be an effective way to see the big picture, deal with complex situations, and create effective long-term management alternatives for the ranch. Successful management alternatives will provide flexibility to protect the core business (i.e., cow herd), be enterprise-diverse to spread risk, and allow management for the good of the whole, not simplyto maximize the pieces. It is important to evaluate your own ranching system to identify the appropriate enterprises or practices, there is no best mix.

Biofuel feedstock and blended coproducts compared with deoiled corn distillers grains in feedlot diets: Effects on cattle growth performance, apparent total tract nutrient digestibility, and carcass characteristics

Crossbred steers (British × Continental; = 192; initial BW 391 ± 28 kg) were used to evaluate the effects of feeding ethanol coproducts on feedlot cattle growth performance, apparent nutrient digestibility, and carcass characteristics. Steers were blocked by initial BW and assigned randomly to 1 of 6 dietary treatments within block. Treatments (replicated in 8 pens with 4 steers/pen) included 1) control, steam-flaked corn-based diet (CTL), 2) corn dried distillers grains with solubles (DGS; DRY-C), 3) deoiled corn dried DGS (DRY-CLF), 4) blended 50/50 corn/sorghum dried DGS (DRY-C/S), 5) sorghum dried DGS (DRY-S), and 6) sorghum wet DGS (WET-S). Inclusion of DGS was 25% (DM basis). The DGS diets were isonitrogenous, CTL was formulated for 13.5% CP, and all diets were balanced for ether extract. Final shrunk BW, ADG, and DMI did not differ among CTL and DGS treatments ( ≥ 0.19). Overall G:F did not differ from CTL for DRY-C, DRY-CLF, or WET-S ( ≥ 0.12); however, G:F was 9.6% less for DRY-S compared with CTL ( < 0.01) and tended ( = 0.09) to be less for DRY-C/S than CTL. For grain source, ADG and G:F were less for DRY-S vs. DRY-C ( < 0.05), but blending DRY-C/S tended ( = 0.07) to increase ADG and increased ( = 0.05) carcass-adjusted G:F vs. DRY-S. For WET-S, final BW and ADG were greater ( < 0.05), and G:F tended ( = 0.06) to be greater than for DRY-S. There was no difference in ADG, DMI, or G:F of steers fed DRY-C vs. DRY-CLF ( ≥ 0.35). Apparent DM and OM digestibility did not differ for CTL, DRY-C, DRY-CLF, and WET-S ( ≥ 0.30) but were lower for DRY-C/S and DRY-S ( < 0.05). Nutrient digestibility was lower for DRY-S vs. DRY-C ( < 0.01), but apparent digestibility of OM, DM, NDF, ADF, CP, ether extract, and starch were increased ( < 0.01) for DRY-C/S vs. DRY-S. Although starch digestibility did not differ between DRY-S and WET-S ( 0.18), digestibility of other measured nutrients was greater for WET-S vs. DRY-S ( < 0.01). Ether extract digestibility was greater for DRY-CLF vs. DRY-C ( < 0.05). Carcass weight, dressing percent, and marbling score did not differ between CTL and DGS diets ( ≥ 0.23). For DRY-S, HCW was lower than for DRY-C ( = 0.02); however, compared with DRY-S, HCW tended to be greater for DRY-C/S ( = 0.10) and WET-S ( = 0.07). At a moderately high (25% DM) inclusion, blending C/S or feeding WET-S resulted in cattle growth performance and carcass characteristics similar to those of CTL and corn-based coproducts.

Inoculants to Enhance the Ruminal Degradation of Small-Grain Forage

Abstract Fibrolytic enzymes and microbial inoculants have the potential to improve fiber degradability. A 2 × 2 × 2 factorial experiment was conducted to determine the nutritive value, ruminal degradability, and degradation rates of wheat ( Triticum aestivum L.) and oat ( Avena sativa L.) pretreated with fibrolytic enzyme (xylanase plus cellulase: XC) or bacterial [Promote ASB ( Lactobacillus buchneri and L. plantarum ); PRO] inoculants at two maturities. Forage was harvested twice during the tillering stage (H1 and H2) and a third time as stover (H3). Forage from H1 had less neutral detergent fiber (NDF; 43.8% dry-matter [DM] basis) and acid detergent fiber (ADF; 31.2% DM basis) and greater in vitro true digestibility (IVTD; 78.5%) concentrations than H3 (69.0 and 45.3% DM basis, and 51.9%, respectively). The IVTD was greater for oat (55.0%) than wheat (50.7%). Chemical composition was not affected by inoculant; however, inoculant did affect ruminal degradability and degradation rates. Potentially degradable DM, NDF, and ADF and effective ruminal degradability were greater for wheat and oat at tillering. Treatment of oat or wheat with XC or PRO enhanced potential degradability and reduced undegradable fractions. Both XC and PRO may be used to degrade the fiber fractions of small-grain forage.

CASE STUDY: Profitable marketing and business practices on a South Texas ranch

ABSTRACT In this case study, historic production and financial records of the cow-calf, stocker, and feedlot enterprises of a South Texas ranch for the years 2001 through 2008 were analyzed. Most of the raised calves were sold at weaning. Depending on precipitation and forage, native stocker cattle were bought during the fall and spring and marketed the following spring and summer. The ranch also managed a feedlot operation, buying feeder cattle and selling finished cattle to a local packer. Annual and cumulative profit or loss on a per animal basis was calculated for each enterprise. For comparison, a retained ownership scenario was developed using the accumulated costs and returns from representative cattle of ranch origin retained through the stocker and finishing phase. When compared with retained ownership, the historic production and marketing plan resulted in greater (P

Strategic Management and Ranching: Successfully Planning for the 21st Century

Strategic Management and Ranching: Successfully Planning for the 21st Century DOI:10.2458/azu_rangelands_v30i2_dunn2