Know how. Know now. Jerry D. Volesky Walter H. Schacht University of Nebraska-Lincoln Ethanol CoProduct Conference Grazing Management when Supplementing Co-Products

Supplemental Feeding Purpose –Meet livestock nutrient requirements –Maximize forage intake and use efficiency Generally thought of as a dormant season practice

Why Supplement in the Growing Season? Decrease forage intake – extend forage supply (drought) and/or enable more animals to be carried for a set time period on the grazing unit Replace pasture forage with a relatively inexpensive alternative Improve grazing distribution – increase the proportion of the grazing unit that is properly used

Northern $/Month/Cow-calf pair $33.85 (B. Johnson)

Substitution Dormant season – substitution most likely to occur when forage is abundant and livestock gains are good Growing season – substitution can be 1:1 when feeding high concentrate supplement on medium to high quality forages

ExperimentControl ADGlb forage/lb DG b NEBR '03 a NEBR '05 a NEBR '05 a NEBR '06 a NEBR '07 a NEBR '07 a Mean Distillers Grains Substitution Klopfenstein et al. 2007

Factors Influencing Substitution Nutrient content/forage quality and palatability of supplement and pasture grass –Level of substitution tends to increase with decreasing nutrient content (increasing NDF) of supplement –Level of substitution is low with DG, especially early in the season when pasture grass is very palatable and nutritious –Level of substitution can be high (1:1) with mixtures of WDG and high-fiber roughages (e.g., high-NDF straw); relative palatability of pasture grass and mixture appears to be important

Supplemented cattle grazing paddock at GSL

Order: Late June Treatment:CON a SUP b 2X c Year 1 Pre-graze Post-graze % Utilization d Year 2 Pre-graze Post-graze % Utilization d DDGS on Summer Pasture Gustad et al. 2008

DDGS on Summer Pasture Order: Mid July Treatment:CONSUP2X Year 1 Pre-graze Post-graze % Utilization d Year 2 Pre-graze Post-graze % Utilization d Gustad et al. 2008

DDGS on Summer Pasture Order: Mid August Treatment:CONSUP2X Year 1 Pre-graze Post-graze % Utilization d Year 2 Pre-graze Post-graze % Utilization d Gustad et al. 2008

Forage Utilization: 55:45 Grass Hay and WDGS Nuttelman 2009 CONSUPP2XSE DMI lb/d Green Supp Standing forage Pre-grazing Post-grazing 833 c 663 b 533 a 9 % Utilization 33.8 a 51.1 b 56.8 c 0.51 ab Means with different superscripts differ (P-value < 0.05)

Performance: 55:45 Grass Hay and WDGS Nuttelman 2009 CONSUPP2XSE Initial BW, lb Cow Calf Final BW, lb Cow Calf ADG, lb Cow a 0.55 b a 0.08 Calf 1.80 a 2.35 b 1.65 a 0.03 ab Means with different superscripts differ (P-value < 0.05)

Nuttelman 2009 Results: 70:30, 60:40, 50:50 Straw CONLOWMEDHISEP-Value Initial BW, lb Cow Calf Ending BW, lb Cow 874 a 899 a 905 a 945 b Calf ADG lb/d Cow Calf ab Means with different superscripts differ (P-value < 0.05)

Results CON70:3060:4050:50SE P- Value Standing Forage Pre lb/acre Post lb/acre Disappearance < 0.01 % Utilization Forage quality CP % NDF % IVOMD % Nuttelman 2009

CON70:3060:4050:50SE P- Value Disappearance lb/d Green 25.3 a 13.4 b 16.5 b 16.3 b 1.3< 0.01 Mix-- a 12.8 b 12.6 b 13.0 b 0.3< 0.01 NDF intake lb/d Grazed intake Mix < 0.01 ab Means with different superscripts differ (P-value < 0.05) Results Nuttelman, 2009

Distillers Grains Supplementation DDGS fed on summer pasture –No indication of substitution Grass hay and WDGS mixture on summer pasture –Replaced 13.5% of grazed forage intake 60.3% NDF 70:30 wheat straw/ WDGS on summer pasture –Replaced grazed forage intake 1:1 basis 76.1% NDF Straw (6.6 lb of NDF) Replaced 6.4 lb of grazed forage intake

Factors Influencing Substitution Grazing pressure and pasture size –Consumption of WDG/straw mixtures more likely assured with higher grazing pressures and smaller pastures Influence of high grazing pressure on stocking rate and pasture degradation

Factors Influencing Substitution Daily supplementation timing –Grazing time and forage intake generally favored by early afternoon vs. early morning feeding Experience with supplement –Young animals less likely to adapt readily to supplementation – training may be required Amount of supplement fed? –Substitution constant across all feeding levels?

Elements of Good Grazing Management 1.Stocking rate 2.Timing of grazing (season of use) 3.Distribution 4.Kind/class of livestock

Stocking Rate – proper (moderate)

Stocking Rate – too heavy

Stocking Rate – way too heavy

Challenges Can high intake of WDG/straw be realized on highly palatable and nutritious pasture grass? How to manage grazing so to take advantage of the potential benefits of WDG/mixtures?

Potential Grazing Protocol No supplementation in early season (vegetative stage) because of relatively low palatability of mixture Begin supplementing at elongation stage when palatability and nutrient content of mixture is relatively high Consider feeding variable amounts of mixture based on forage availability, grazing pressure, etc. Short duration grazing is best match because managing for high grazing pressure?

Nutrient Transfer and Management Approximate nutrient concentration in distillers grain co-products (DM basis) Nitrogen (N) 4.80% Phosphorus (P) 0.85% Sulfur (S) 0.58% Feedlot work: Regassa et al. (amount in diets, manure, feedlot size, crop acres, crop use, economics)

Nutrient Transfer Grazing: – Winter range and cake – Stocking: 0.60 AUM/acre, 90 days – 2 lb DDG cube/hd/day (1200 lb cow) Potential nutrient amount (from DDG supplement) transferred to pasture. Nitrogen (N) 0.72 lb/ac Phosphorus (P) 0.25 lb/ac Sulfur (S) 0.17 lb/ac

Nutrient Transfer GSL Grazing Studies: – Gustad (2006) – Double-stocking: 1.20 AUM/acre – 5 lb DDG/hd/day (540 lb yearling) Potential nutrient amount (from DDG supplement) transferred to pasture. Nitrogen (N) 16.3 lb/ac Phosphorus (P) 2.9 lb/ac Sulfur (S) 2.0 lb/ac

Nutrient Transfer GSL Grazing Studies: – Nuttelman (2008) – Double-stocking: 1.20 AUM/acre – WDG (55%) + grass hay (45%) – 14.6 lb WDG+hay/hd/day (cow-calf pairs) Potential nutrient amount (from WDG+hay supplement) transferred to pasture. Nitrogen (N) 12.9 lb/ac Phosphorus (P) 2.1 lb/ac Sulfur (S) 1.6 lb/ac

Questions – Discussion