Supplementing Beef Cows

1. Supplementing Beef Cows

3. Steps to an Effective Cow Nutrition Program • Determine nutrient requirements • Estimate nutrients available from forage • Determine supplemental needs • Evaluate supplement alternatives

4. Body Condition is a Key Element in Nutritional Management Decisions

5. Body Condition Goals at Calving Mature cows 5 2-year-olds 6

6. Steps to an Effective Cow Nutrition Program • Determine nutrient requirements • Determine nutrients available from forage • Determine supplemental needs • Do the math • Monitor the cows • Evaluate supplement alternatives

7. Science and related tools can help to make informed decisions Observations can help adjust to specific conditions

8. Beef cows’ requirements vary with the production cycle Grazed forage quality and availability changes over time

9. Resources • Nutrient requirements • Beef Cattle Manual, chapter 16 • Extension bulletins: E-974, Nutrient Requirements of Beef Cattle • National Research Council: Nutrient Requirements of Beef Cattle • Monitor mature cow weight at weaning adjusted to BCS 5 • Monitor herd sire EPD’s over time • Increasing genetic trend for milk, weaning weight, yearling weight, and carcass weight related to increasing nutrient requirements

10. Resources • Nutrients available from forage • Book values: • Beef Cattle Manual, chapter 17 • Extension bulletins and other publications: ANSI-3018 • National Research Council: Nutrient Requirements of Beef Cattle • Grazed and harvested forage monitoring • Harvested hay samples and quarterly (or more frequently) forage sampling using hand-plucking technique • Commercial laboratory analysis • Consistency and continuity over time is key

11. Certified Laboratories foragetesting.org

12. Determine Supplemental Needs Nutrients from forage - Nutrient requirements Nutrient excess or deficiency

13. Effective Nutrition Program • Balance nutrient supply with nutrient requirements • Overfeeding any nutrient is unnecessary and expensive • Ignoring a substantial deficiency can be devastating • Optimize cost, performance, convenience and ancillary benefits

14. Calculating Supplemental Need • Spring calving cow grazing native rangeland: 1,100 lb cows • Determine daily protein and TDN (energy) requirement from Table 16.2 (page 138) • Protein = 1.8 lb./d • TDN = 12.1 lb./d • Estimate protein and TDN concentration in the forage from Table 17.1 (page 158) • Protein = 4% • TDN = 49%

15. Calculating Supplemental Need • Estimate DM intake • Table 16.1 or 16.2 (will not be exactly the same) • 1.8 to 2% of body weight or ? lb? • About 22 lb • Determine daily intake of protein and TDN • 22 x 0.04 = ? • 22 x 0.49 = ?

16. Supplemental Need Calculating Supplemental Need • Compare requirement to supply Protein TDN Required 1.8 lb. 12.1 lb. Supplied 0.88 lb. 10.8 lb. Difference 0.92 lb. 1.3 lb.

17. Supplement Amount • Divide supplemental need by supplement nutrient concentration to determine appropriate amount of supplement How many lbs of 20 %? .92 / .20 = 4.6 How many lbs of 25 %? .92 / .25 = 3.7 How many lbs of 38 %? .92 / .38 = 2.4

18. Supplement Decisions • Once supplement amount needed to fix protein deficiency (if one exists) is determined, compare energy supplied, cost, convenience and other factors

19. Supplement Decisions How much TDN will be supplied by each alternative compared to the requirement? Assume all supplements contain 75% TDN. Supplement alternative 20% 25% 38% Lb. per day 4.6 3.7 2.4 TDN per day 3.5 2.8 1.8 Sup need 1.3 1.3 1.3 Difference 2.2 1.5 0.5

20. Supplement Decisions Supplement alternative20% 25% 38% Lb. per day4.6 3.7 2.4 Cost per lb.$.15 $.17 $.19 Cost per day$.69 $.63 $.46 vs. 20%, 90 days $5.40 $20.7

22. Supplementation PrioritiesEvaluate Protein First

23. Improved Intake and Digestibility Results in Better Performancea 2 lb. / d of 40% No Sup Cow wt. change +23 lb. -153 lb. BCS change -.3 -1.6 Weaning weight 484 448 Steele et al., 2002 aTreatments applied for about 90 days during late gestation

24. Rule of Thumb: Forage with 8% CP or more fed during mid-gestation will not require a protein supplement Don’t Purchase Protein Supplement That is Not Needed

25. Protein Source

26. Protein Sources “Natural” or Plant Proteins

27. Protein Sources • Non-protein nitrogen • urea • biuret • uric acid (poultry litter) • ammonium sulfate

28. Effect of Urea or Natural Protein Supplements on Forage Intake Adapted from Minson, 1990

29. Non-protein nitrogen as a protein source OSU, 1967

30. Improving NPN utilization NPN sources are better utilized when: • More mature cattle: > 600 lbs. • .5% or more of body weight concentrate is fed • Dietary protein is marginally deficient (1 to 3% gap) • Natural PTN and NPN are blended • Animals allowed access > 1 time/day

31. Cost vs. Convenience • Do your own math • Only you can decide what the convenience factor is worth

32. Interval Feeding • Saves labor and equipment • Every-other-day or 3 days per week (M, W, F) works well • Effective with plant-based protein supplements • Limited to less than 1% of body weight per feeding

34. Using Small Grains Pasture“Interval or Limit Grazing” • 15 to 30% protein, DM basis • In one 3 to 4 hr. grazing bout, cows consume 2 to 3 lb. of protein from forage • Cows can consume hay or graze winter pasture 1 to 4 days for each 4-hr. grazing bout (see Table 21.7)

35. Summary • Use the logical approach to establish a cost effective program that results in acceptable performance • This program can be fine tuned or replaced over time when and if necessary • Changing conditions warrant evaluation of traditional plans and programs