Indexing hay quality to dairy cattle performance Randy Shaver Dairy Science Department University of Wisconsin - Madison
Forage quality of alfalfa in Kawas trial Pre Bloom Early Bloom Mid Bloom Full Bloom Percent (dry matter basis) CP 21.1 18.9 14.7 16.3 ADF 30.2 33.0 38.0 35.9 NDF 40.5 42.0 52.5 59.5 UWEX From Kawas et al. 1989 Dan Undersander-Agronomy 2004
Effect of forage quality FCM at four concentrate levels 90 4% FCM (lb/day) 80 70 60 50 20% 37% 54% 71% 40 Prebloom Early bloom Mid bloom Full bloom UWEX Alfalfa maturity stage From Kawas et al. 1989 Dan Undersander-Agronomy 2004
Effect of forage quality on dry matter intake (lb/day) 60 55 50 45 40 35 20% 37% 54% 71% 30 Prebloom Early bloom Mid bloom Full bloom Alfalfa Maturity UWEX Dan Undersander-Agronomy 2004
Relative Feed Value = (Intake Potential * Digestible DM) Constant UWEX Dan Undersander-Agronomy 2004
Relative Feed Value Intake Potential = 120/NDF Digestible DM = 88.9 - (0.779*ADF) Constant = 1.29 UWEX Dan Undersander-Agronomy 2004
Relative Feed Value Intake Potential = 120/NDF Digestible DM = 88.9 - (0.779*ADF) Constant = 1.29 UWEX Dan Undersander-Agronomy 2004
Sampling of Empirical equations From Western Region %TDN = 82.38 - (0.7515 x ADF) From Pennsylvania %TDN = 4.898 + (89.796 x NEL) NEL (Mcal/lb) = 1.044 - (0.0119 x ADF) From Midwest %DDM = 88.9 - (0.779 x ADF) UWEX Dan Undersander-Agronomy 2004
TDN Estimates from Different Empirical Equations TDN 80 75 70 65 60 55 50 45 40 35 30 UWEX 20 30 40 50 60 Acid Detergent Fiber (%) Western Pennsylvania Midwestern Dan Undersander-Agronomy 2004
NRC (2001) Dairy TDN TDN 1-X = tdcp + (tdfa x 2.25) + tdndf + tdnfc -7
Lignin Content of Legume-Grass Forages Dairy NRC, 2001 DM Basis Predominantly Grass Early Cut Late Cut Predominantly Legume Early Cut Late Cut Average 5.0% 6.5% 6.7% 8.4%
Relationship between lignified NDF and ivndfd for corn & alfalfa forages In vitro NDF digestibility, %, 30h 70 60 50 40 30 20 Corn Silage R 2 = 0.54 Alfalfa R 2 = 0.56 0 5 10 15 20 25 Corn silage: 3-9% Alfalfa: 11-20 % Allen, 2003 Lignin, % of NDF
80 IVNDFD vs Lignin % of NDF 60 % NDF 40 % of NDF y = -4.5303x + 82.824 R 2 = 0.4954 20 3.00 6.00 9.00 12.00 Lignin, % of DM UWEX Data from DairyOne, NY Dan Undersander-Agronomy 2004
Does not consider NDF digestibility! Relative Feed Value Intake Potential = 120/NDF Digestible DM = 88.9 - (0.779*ADF) Constant = 1.29 UWEX Dan Undersander-Agronomy 2004
Relationship of IVNDFD to ADF for Alfalfa Comparison of ADF to Fiber Digestibility of World's Forage Superbowl Samples, 2003 Neutral Detergent Fiber Digestibility (% of NDF) 75 70 65 60 55 50 45 40 35 30 y = -0.3822x + 61.224 R 2 = 0.0901 20 22 24 26 28 30 32 34 36 38 40 Acid Detergent Fiber (% of DM) UWEX Dan Undersander-Agronomy 2004
ivndfd
Response to alfalfa hay NDF & NDFD 1 Llamas-Lamas and Combs, UW Madison Item Early Veg. Full Bloom Hay NDF, % 36 52 Hay NDFD, % of NDF 65 42 Diet, % Hay % NDF % NDF from hay 68 32 24 45 31 23 DMI, kg/d 26.1 a 24.8 b FCM, kg/d 1 30.6 29.2 1 P < 0.10
Response to wheat straw NDF & NDFD Kendall and Combs, UW Madison LNDF LNDFD LNDF HNDFD HNDF LNDFD HNDF HNDFD Diet NDF 28% 28% 32% 32% Diet NDFD 47% 53% 46% 54% DMI, lb/d 50 52 48 49 FCM, lb/d 79 b 82 a 73 y 76 x Diets 8.5% to 16% control or ammoniated wheat straw 41 to 62% NDFD wheat straws
Impact of IVNDFD (Oba and Allen, 1999) For every 1%-unit increase in IVNDFD 0.37 lb DMI 0.55 lb FCM
48-h ivndfd in Legume Forages % of NDF 1 Std Dev Average 1 Std Dev Dairyland 2002-2007 n=200/yr. Dairy One 2003-2007 n=400/yr. Rock River 2003-2007 n=700/yr. 45% 50% 55% 47% 52% 57% 43% 49% 55%
30-h ivndfd in Legume Forages % of NDF 1 Std Dev Average 1 Std Dev Dairy One 2002-2007 n=300/yr. CVAS 2004-2005 n=350/yr. 42% 48% 54% 39% 45% 51%
Factors Affecting Hay NDF & IVNDFD Crop--i.e. Legume vs. Grass Variety--i.e. grasses; low-lignin alfalfa Stage of Maturity Cutting Climatic Conditions Heat Damage
Relative Forage Quality (RFQ) = (dintake Potential * dtdn) Constant UWEX Dan Undersander-Agronomy 2004
Relative Forage Quality Intake potential = base intake plus adjustment for dndf = base intake + ((dndf-average dndf) *.374) =(0.012/NDF) + (NDFD-45)*0.374*1350/100 From Oba and Allen, 1999, J Dairy Sci UWEX Dan Undersander-Agronomy 2004
Relative Forage Quality Total Digestible Nutrients (dtdn) = dnfc + dcp + dfa*2.25 + dndf - 7 = [(NFC*.98) + (CP*.93) + (FA*.97*2.25) + NDF * NDFD] - 7 From NRC, 2001 UWEX Dan Undersander-Agronomy 2004
Relative Forage Quality (RFQ) RFQ = dintake potential*dtdn 1.23 UWEX Dan Undersander-Agronomy 2004
RFV vs. RFQ NDF ADF NDFD dtdn dintake Forage A 40 30 58 61.6 31.0 Forage B 40 30 36 53.6 22.8 RFQ RFV Forage A 151 152 Forage B 112 152
Comparison of RFV and RFQ for Hay, Haylage, and Baleage, 2002 Worlds Forage Superbowl 300 250 y = 1.1446x - 32.224 R 2 = 0.8623 200 RFQ 150 100 50 50 100 150 200 250 300 RFV UWEX Dan Undersander-Agronomy 2004
Comparison of RFV and RFQ for Hay, Haylage, and Baleage, 2002 Worlds Forage Superbowl RFQ 300 250 200 150 100 y = 1.1446x - 32.224 R 2 = 0.8623 Dissatisfied Seller Dissatisfied Customers 50 100 120 140 160 180 200 220 240 260 280 300 RFV UWEX Dan Undersander-Agronomy 2004
Relationship of RFV to RFQ in Alfalfa, World s Forage Superbowl, 2003 350 Above line * energy not valued * dissatisfied seller Below line * poor animal performance * dissatisfied customers * heat damaged samples UWEX Relative Forage Quality 300 250 200 150 100 y = 0.8204x + 45.06 R 2 = 0.51 100 150 200 250 300 Relative Feed Value Dan Undersander-Agronomy 2004
Uses of RFQ When to harvest Allocation of forages to animals Buying/selling forages Contracting for harvest with quality incentive UWEX
Matching Relative Forage Quality to Animal Needs Dairy heifers, 18-24 mo. Dry beef or dairy cows Dairy heifers, 12-18 mo. Beef cows with calf Dairy cows, last 200 days lactation. Dairy calves, 3-12 mo. Beef stocker cows Dairy, first 100 days of lactation. Calves, first 3 mo 100 110 120 130 140 150 Relative Forage Quality
Weekly Hay Market Demand and Price Report for the Upper Midwest as of February 26, 2010 Data Compiled by Ken Barnett, UW-Extension
Visit UW Extension Dairy Cattle Nutrition Website http://www.uwex.edu/ces/dairynutrition/