Jerry D. Volesky Walter H. Schacht University of Nebraska-Lincoln

1. Grazing Management when Supplementing Co-Products Jerry D. Volesky Walter H. Schacht University of Nebraska-Lincoln Ethanol CoProduct Conference - 2009

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

3. 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

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

5. 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

6. Distillers Grains Substitution Klopfenstein et al. 2007

7. 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

8. Supplemented cattle grazing paddock at GSL

10. DDGS on Summer Pasture Gustad et al. 2008

11. DDGS on Summer Pasture Gustad et al. 2008

12. DDGS on Summer Pasture Gustad et al. 2008

13. Forage Utilization: 55:45 Grass Hay and WDGS Nuttelman 2009

14. Performance: 55:45 Grass Hay and WDGS Nuttelman 2009

15. Results: 70:30, 60:40, 50:50 Straw Nuttelman 2009

16. Results Nuttelman 2009

17. Results Nuttelman, 2009

18. 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

19. 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

20. 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?

21. Elements of Good Grazing Management • Stocking rate • Timing of grazing (season of use) • Distribution • Kind/class of livestock

22. Stocking Rate – proper (moderate)

23. Stocking Rate – too heavy

24. Stocking Rate – way too heavy

25. 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?

26. 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?

27. Nutrient Transfer and Management Feedlot work: Regassa et al. (amount in diets, manure, feedlot size, crop acres, crop use, economics)

28. Nutrient Transfer • Grazing: • Winter range and cake • Stocking: 0.60 AUM/acre, 90 days • 2 lb DDG cube/hd/day (1200 lb cow)

29. Nutrient Transfer • GSL Grazing Studies: • Gustad (2006) • Double-stocking: 1.20 AUM/acre • 5 lb DDG/hd/day (540 lb yearling)

30. 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)

33. Questions – Discussion