Supplements for Beef Cows Example forage analysis Nutrient

Supplements for Beef Cows • Example forage analysis Nutrient DM Crude protein NDF ADF % 88. 0 8. 5 65. 0 36. 0

Supplements for Beef Cows • • Estimate DM intake DMI, %BW = (120/%NDF) DMI, %BW = (120/65) = 1. 85% BW 1, 200 lb cow x 0. 0185 = 22. 2 lb DMI

Supplements for Beef Cows • Estimate CP intake • 22. 2 lb DMI x 0. 085 = 1. 89 lb CP

Supplements for Beef Cows • • • Estimate TDN intake TDN, % = 88. 9 – (0. 779 x %ADF) TDN, % = 88. 9 – (0. 779 x 36) TDN, % = 60. 9% 22. 2 lb DMI x 0. 609 = 13. 5 lb TDN intake

Supplements for Beef Cows • Are requirements being met? • Late gestation requirements CP TDN Late gestation Estimated intake Difference 2. 12. 6 lb 0 lb 1. 13. 89 lb 5 lb - 0. 9 lb 0. 11 lb

Supplements for Beef Cows • Are requirements being met? • Lactation – superior requirements CP TDN Lactation – superior Estimated intake Difference lb 2. 9 15. 7 lb 1. 8 13. 9 lb 5 lb - -2. 2 lb 1. 01 lb

Supplements for Beef Cows • Do I need a protein or energy supplement? • Both contain CP and energy • Difference is relative concentration of CP

Supplements for Beef Cows • Protein supplements usually have 25% CP or higher • Energy supplements usually have less than 15% CP • Calculate first limiting nutrient

Late Gestation • • • CP supplied/CP required 1. 89 lb/2. 0 lb = 0. 95 or 95% TDN supplied/TDN required 13. 5 lb/12. 6 lb = 1. 07 or 107% First limiting nutrient is CP

Late Gestation • CP needed = 0. 11 lb • Corn gluten feed – 22% CP, 80% TDN • 0. 11 lb/0. 22 = 0. 5 lb corn gluten feed

Lactation – Superior • • • CP supplied/CP required 1. 89 lb/2. 9 lb = 0. 65 or 65% TDN supplied/TDN required 13. 5 lb/15. 7 lb = 0. 86 or 86% First limiting nutrient is CP

Lactation – Superior • CP needed = 1. 01 lb • Corn gluten feed – 22% CP, 80% TDN • 1. 01 lb/0. 22 = 4. 6 lb corn gluten feed • 4. 6 lb x 0. 80 = 3. 7 lb TDN added