Basic Beef Cow Nutrition Katherine Whitman, DVM, MS Great Plains Veterinary Educational Center

Basic Beef Cow Nutrition

Katherine Whitman, DVM, MSGreat Plains Veterinary Educational Center

Overview

• Recognizing a problem• Basic requirements•Matching cow cycle with forage cycle• Critical time points in the cow cycle• Evaluating feedstuffs• BRaNDS program application• Nutrition in practice

Obvious…

…Sub-clinical

How do we know?• Tools to evaluate nutritional status• Body Condition Scoring

• https://beef.unl.edu/learning/condition1a.shtml• Behavior?

• Health issues• Increases is morbidity or mortality• Unthrifty• Ineffective preventatives, treatments

• Performance issues• Reproductive deficiencies• Poor growth

Nutritional Requirements• NRC for technicals• Minimum requirements• Feed values are averages

• Feed analysis is under utilized!!• Sampling-what feedstuffs?

What does she need?• Age?• Stage of production?• Body condition?• Environment?• Feedstuffs available?• Producer goals?

Changes in requirement

Production Cycle

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC

1ST 2ND 3RD

Lactation

Grazing Supplement?

Nutritional Demands

• Demands vary with physiologic state of cow• Trimester• Lactation• Growth• Other stressors

Determining What to Feed

•Availability•Cost• Feasibility•Quality

Feedstuff Evaluation

• Testing• LOOK!!!• Ask questions

What is the Focus?

• Major balancers• Protein: 8% Cows, 13-14% Heifers

(MINIMUMS!!)• Energy: TDN, NEm, NEg, NEl

• Ca:P ratio-what is appropriate?• Adjustments• Supplementation??

Forage dry matter intake relative to forage crude protein concentration Source: Adapted from Moore and Kunkle, 1995

Carbohydrate Fractions

Total Carbohydrate

Nonfiber Carbohydrate

Organic Acids SugarsStarches (NSC)

Neutral Detergent

Soluble Fiber

Pectins

Fructans

ß-Glucans

Structural Carbohydrate

(NDF)

HemicelluloseAcid Detergent

Fiber

Cellulose

Lignin

Maillard Protein

Stimulate Fermentation

Stimulate Milk Production

Decrease Intake Increase Milk fat

• 2 Year Olds 1560• 3 Year Olds 1242• Matures 5894

• Calving season begins March 21• Wean October 20• Turned out to winter grazing• Winter ration?• Other questions?

Case background

Feeding options• Supplemental forages• Supplemental concentrates• Corn stalks• http://

www.ianrpubs.unl.edu/epublic/live/ec290/build/ec290.pdf• Dry lot• http://

www.ianrpubs.unl.edu/epublic/pages/publicationD.jsp?publicationId=1639

• https://beef.unl.edu/confinement-cows-series-part-1-nutritional-considerations

Reading Feed Analysis As Fed 100% Dry MatterMoisture, % 7.3

Dry Matter, % 92.7

Crude Protein, % CP 19.5 21.0

Acid Detergent Fiber, % ADF 26.6 28.7

Neutral Detergent Fiber, % NDF 35.4 38.2

Total Digestible Nutrients, % TDN 65.3 70.4

Net Energy, Maint, Mcal/lb 0.70 0.75

Net Energy, Gain, Mcal/lb 0.44 0.47

Net Energy, Lact, Mcal/lb 0.68 0.73

Digestible Energy, Mcal/lb 1.31 1.41

Met. Energy, Beef, Mcal/lb 1.07 1.16

Relative Feed Value, (RFV) 162

Calcium, % Ca 1.18 1.28

Phosphorus, % P 0.27 0.29

Magnesium, % Mg 0.25 0.27

Potassium, % K 2.93 3.16

Near Infrared Reflectance Spectroscopy (NIRS) Analysis

Ration formulation

• Scratch paper• Rules of Thumb

• Excel spreadsheets• Numerous online resources

• Software programs• BRaNDS• BRaNDS.xlsm

• NRC• D:\NRC\UNL Practicum Revised NRC - Novemb

er 2013.xls