Grouping Strategies to Improve Feed Efficiency V.E. Cabrera University of Wisconsin-Madison Dairy Science 26th DISCOVER Conference on Food Animal Agriculture: Dairy Feed Efficiency. September 23-26, 2013 Northern Illinois University Conference Center in Naperville, IL. Hosted by the American Dairy Science Association
Feeding all lactating cows equally A larger number of cows are overfed Same ration (TMR) to all cows (groups) All lactating cows receive same nutrient density diet Preferred high rations Low producing animals receive more nutrients than required One diet for all Would never optimize production and efficiency VandeHaar, 2011
Improve feed efficiency + feeding groups (precision feeding) Improved nutrient use efficiency Diet closer to cow requirements Less nutrient excretion Decreased environmental concerns Wang et al., 2000 Less overfed animals Decreased over conditioned cows Lower feeding costs Higher milk income over feed cost
Why farmers do not group more? Trying to find most important constraints 2-page mailed survey 25% feeding same ration to all lactating Reported constraints 1 Perception milk drops 2 Keep mgt. simple 3 Conflicts w/reproduction 4 Facilities do not allow Results (responses) ~200 Wisconsin farms 5 Don t believe are needed 6 Nutritionist don t want 7 Labor or personnel Contreras-Govea et al., 2013
A simulation study...
Strategies for grouping cows Depend on farm and herd characteristics Individual cow nutrient requirements Energy Protein Farm characteristics Capacity to handle lactating feeding groups Number of lactating cows on the herd Adapted from McGilliard et al., 1983; St-Pierre and Thraen, 1999
Cow nutrient requirement Energy Daily total net energy (NEtotal) NEtotal (Mcal) = NEmaintenance + NEmilk + NEBW change NEmaintenance = 0.079 x BW 0.75 NEmilk = DailyMilk x (0.0929 Fat% + 0.0547 Protein% + 0.192) NEBW change = Table from NRC, 2001 NRC, 2001
Cow nutrient requirement Protein Daily total crude protein (CPtotal) CPtotal (g) = CPmaintenance + CPmilk CPmaintenance = 104.78 + 0.73 x BW - 0.00015432 x BW 2 CPmilk = DailyMilk x (4,586+1,036 x Fat%)/100 McGilliard et al., 1983
Cow feed requirement Dry matter intake Daily total dry matter intake (DMI) DMI (kg) = (0.372 x 4% FCM + 0.0968 x BW 0.75 ) x (1 - e (-0.192 x ((DIM/7) + 3.67) ) 4% FCM = 0.4 x Milk + 15 x (Fat%/100) x Milk NRC, 2001 NE (Mcal/kg DMI) = NEtotal(Mcal)/ DMI (kg) CP (%/kg DMI) = (CPtotal(g)/1,000) / DMI (kg)
Milk (and components) Cow-specific lactation curves Milk based on Herd ME305 Cow PPA or ME305 Milk, kg Stochasticity 22 50 43 36 29 Lact 1 Lact 2 Lact > 2 Components 61 122 183 244 305 Herd Stochasticity Base function Woods Adjusted Woods Component, kg 1.8 1.62 1.44 1.26 1.08 2 nd lactation Fat Protein 61 122 183 244 305 De Vries, 2001 Days after calving
Initial individual cow BW Seed BW 2. Not available from farm records: Triangular distribution + Lactation + State of lactation 1. Available from farm records 700 550 1,000 794 Holstein BW records from 2 Wisconsin farms
Daily BW changes Important for maintenance requirements Based on Lactation DIM Stochasticity Body weight, kg 625 610 595 580 565 Lactation > 1 (mean=600 kg) Mean=600 kg 200 400 600 800 Days after calving Korver et al., 1985 function Described by van Arendonk, 1985 fitted to NRC, 2001
Nutrient requirement for a group Energy and protein NEgroup (Mcal) = 83 rd Percentile of (NEgroup_cows) CPgroup (%) = 83 rd Percentile (CPgroup_cows) Stallings and McGilliard, 1984 St-Pierre and Thraen, 1999 CP Cluster Seems to be MOST efficient criterion for grouping NEl McGilliard et al., 1983 St-Pierre and Thraen, 1999
Value of NE, CP, and milk Determine diets cost (August 2013) Using referee feeds Petersen method St-Pierre and Giamocic, 2000 Corn: 9% CP + 2 Mcal/kg = $0.267/kg SBM: 54% CP + 2.2 Mcal/kg = $0.587/kg Price NE and CP NE ($/Mcal) = 0.116 CP ($/kg) = 0.747 Price of milk $0.412/kg http://future.aae.wisc.edu/ http://dairymgt.info/tools/feedval_12/index.php
Nutritional grouping Two main types of groups Obligated groups Fresh (< 22 DIM) Dry (~> 220 DCC) Daily assigned Optional groups 1 to 6 additional groups Daily assigned Monthly re-grouped
Optimize cows to a feeding group Maximize the income over feed cost Non-linear optimization Iterative process (all permutations) Search for global maxima IOFC Max(IOFC) = SUM(IOFCgroup) IOFCgroup = Milk Valuegroup - Feed Costgroup Cabrera, 2012
Cow and herd simulation Monte Carlo approach Next event scheduling Pregnancy Abortion Dry-off Parturition Involuntary culling Death Immediate replacement After a cow leaves the herd Two-step 1. Binary outcome of event: Happens or not E.g., uniform distribution 2. DIM of the occurrence When it happens E.g., Weibull distribution Replicates 1,000 replicates for each cow within specific herd
Cow simulation Follows actual COW card Variable Unit Description Cow ID # Cow identification Parity # Lactation DIM d Days in milk, days after calving DCC d Days in pregnancy (DIP) Fat % Fat component on milk Protein % Protein component on milk (%) PPA* % Predicted producing ability ME 305* kg/305 d Mature equivalent milk production BW kg Live body weight *Either PPA or ME305 used to assess cow s milk class. PPA preferred if available
Herd simulation Nutritional grouping baseline information Parameter Herd ME 305 Diet formulation 1 group Description Herd production level 83 rd percentile Diet formulation + groups 83 rd percentile Size for optional groups Groups size flexibility Milk depression when new group-pen Same size groups Adjust herd dynamics (i.e., dry-off freshening) 1.82 kg/d for 5 d
Studied herds All data collected at the cow-level Herd (size) 570 787 727 331 1460 Herd ME 305, kg 1 st lactation, % Average DIM 21-d PR, % Culling risk, % Abortion, % BW available 16,140 12,884 13,897 13,348 14,188 43 39 39 38 45 187 178 201 208 189 18 19 19 17 18 32 37 36 35 40 7 11 11 16 7
...And we are finding
Herd 787, nutritional diets 1.8$ 1.7$ $1$Group$ 5$Groups$ Energy$in$diet$(Mcal/kg$DM)$ 1.6$ 1.5$ 1.4$ 1.3$ 1.2$ 1$ 2$ 3$ 4$ 5$ 6$ 7$ 8$ 9$ 10$ 11$ 12$ Months after starting simulation
Herd 331, nutritional diets 17%# Crude protein, % DM 15%# 13%# 11%# 17%# 15%# 13%# 11%# 17%# 15%# 1 group 2 groups 3 groups 13%# 11%# 1# 2# 3# 4# 5# 6# 7# 8# 9# 10# 11# 12# Months after starting simulation
1.30% 1.35% 1.40% 1.45% 1.50% 1.55% 1.60% 1.65% 1.70% 1.75% 23% 32% 41% 50% 59% 68% 77% 86% 95% 104% 113% 122% 131% 140% 149% 158% 167% 176% 185% 194% 203% 212% 221% 230% 239% 248% 257% 266% 275% 284% 293% Energy%in%diet%(Mcal/kg%DM)% Days%in%milk,%third%lactaCon% %1%Group% %2%Groups% %3%Groups% %4%Groups% %5%Groups% Cow 6320 (727) = 100% milk Pregnant Dry
Cow 928(727) = 109% milk, 1 yr 50# Possible grouping milk depression 900# Milk%or%DMI%(kg/d)% 40# 30# 20# 10# BW Milk DMI 3 rd Lactation -$27 milk, -$9 feed, -$18 IOFC 800# 700# 600# 500# 400# 300# Body%weight%(kg)% 0#,46# 4# 54# 104# 154# 204# 254# 304# 200# 2.2$ 2$ Days%in%milk% 27%# 25%# 23%# Diet%energy%(Mcal/kg%DM)% 1.8$ 1.6$ 1.4$ 1.2$ 1$ Diet%crude%protein%(%%DM)% +30.3 Mcal 7%# -16.6 kg CP 5%# 0.8$ 3%# )46$ 4$ 54$ 104$ 154$ 204$ 254$ 304$ )46# 4# 54# 104# 154# 204# 254# 304# 21%# 19%# 17%# 15%# 13%# 11%# 9%# Days%in%milk% Days%in%milk%
Cow 6338(727) = 78% milk, 1 yr 50# 3rd Lactation BW 900# 800# Milk%or%DMI%(kg/d)% 40# Milk 30# 20# DMI 700# 600# 500# 400# Body%weight%(kg)% 10# -$23 milk, -$200 feed, +$177 IOFC 0# 27# 75# 125# 175# 225# 275# 325# 375# 300# 200# 2.2$ Days%in%milk% 27%# Diet%energy%(Mcal/kg%DM)% 2$ 1.8$ 1.6$ 1.4$ 1.2$ 1$ Group-pen availability State of cow -846 Mcal 7%# -137 kg CP 5%# 0.8$ 27$ 75$ 125$ 175$ 225$ 275$ 325$ 375$ Diet%crude%protein%(%%DM)% 25%# 23%# 21%# 19%# 17%# 15%# 13%# 11%# 9%# 3%# 27# 75# 125# 175# 225# 275# 325# 375# Days%in%milk% Days%in%milk%
Cow10020(727) = 92% milk, 1 yr 50# 1st Lactation 900# 800# Milk%or%DMI%(kg/d)% 40# 30# 20# Milk BW DMI 700# 600# 500# 400# Body%weight%(kg)% 10# 0# -$18 milk, -$43 feed, +$25 IOFC 2# 52# 102# 152# 202# 252# 302# 300# 200# 2.2$ 2$ Days%in%milk% 27%# 25%# 23%# Diet%energy%(Mcal/kg%DM)% 1.8$ 1.6$ 1.4$ 1.2$ 1$ 0.8$ 9%# -165 Mcal -32 kg CP 7%# 5%# 3%# 2$ 52$ 102$ 152$ 202$ 252$ 302$ 2# 52# 102# 152# 202# 252# 302# Diet%crude%protein%(%%DM)% 21%# 19%# 17%# 15%# 13%# 11%# Days%in%milk% Days%in%milk%
Economic efficiency Income'over'feed'cost'($/cow'per'yr)' $2,575' $2,525' $2,475' $2,425' $2,375' +$61 +$66 +$53 +$43 +$22 +$57 +$47 +$20 +$45 +$19 1' 2' 3' 4' 5' 6' Nutri@onal'groups'' +$55 +$63 +$66 +$70 +$73 331# 570# 727# 787# 1460#
Energy efficiency 63.10%' +0.69% +0.75% +0.73% +0.63% Mcal'milk/Mcal'consumed'(%)' 62.90%' 62.70%' 62.50%' 62.30%' 62.10%' +0.38% +0.58% +1.02% +0.96% +0.93% 61.90%' +0.26% 331# 570# 727# 787# 1460# 61.70%' 1' 2' 3' 4' 5' 6' Nutri@onal'groups''
Nitrogen efficiency Milk%N%produced/Feed%N%consumed%(%)% 26.45%% 26.25%% 26.05%% 25.85%% 25.65%% 25.45%% +0.84% +0.91% +0.93% +0.69% +0.94% +0.75% +0.71% +0.41% +0.61% +0.25% 331% 570% 727% 787% 1460% 25.25%% 1% 2% 3% 4% 5% 6% Nutri@onal%groups%
Effect of milk depression 9.1 kg Δgroup Income%over%feed%cost%($/cow%per%yr,%bars)% $2,620& $2,600& $2,580& $2,560& $2,540& $2,520& Milk&depression& No&milk&depression& -0.07% -0.06% -$23-0.05% -$23 -$21 -$19 -$16 1& 2& 3& 4& 5& 6& Nutri@onal%groups% -0.10% -0.13% 26.70%& 26.50%& 26.30%& 26.10%& 25.90%& 25.70%& 25.50%& Herd 787 Milk%N%produced/Feed%N%consumed%(%,%lines)%
Interaction with culling $2,430' $2,420' Herd 331 Culling'rate' 40%' 32%' Income'over'feed'cost'$/cow'per'yr' $2,410' $2,400' $2,390' $2,380' $2,370' $2,360' $2,350' +$47 +$45 $2,340' 1'Group' NutriBonal'groups' 3'Groups'
Interaction with reproduction Income&over&feed&cost&$/cow&per&yr& $2,480& $2,460& $2,440& $2,420& $2,400& $2,380& $2,360& $2,340& Herd 570 (10 yr run) 21Cd&pregnancy&rate& 10%& 25%& +$52 +$46 $2,320& 1&Group& Nutri?onal&groups& 3&Groups&
A simplified online tool Herd-specific assessments (DairyMGT.info)
Additional costs and benefits Impacts grouping feeding strategies Management cost Additional labor Extra management Avoid costs Additives and supplements savings Milk depression Cow social interactions
Tool illustration Economic impact of grouping Current situation Lactating cows 470 Number groups 1 NEL, Mcal/lb DM 0.80 CP, % DM 17% Possible situation Number groups 3 Group sizes 100, 100, 270 Added cost, $ Milk loss Milk loss time $1,000/month 2.27 kg/cow 4 days Saved cost, $ $0
Decision support system illustration Cluster grouping criteria Cow numbers Possible situation NEL, Mcal/lb CP, % IOFC, $/cow/day Group 1 270 0.71 16.05 9.3 Group 2 100 0.65 14.18 7.2 Group 3 100 0.62 13.07 4.7 x1,000 $1,336 Annual value of grouping $1,189 3 $147,000/470 cows groups no groups Cabrera et al., 2012
Analysis from dairy farm records 30 Wisconsin dairy farms No grouping vs. 3 groups Same size groups Cluster grouping 83 rd percentile CP and NEL Current diet 1.75 Mcal/kg DM 17% CP Same prices for all $0.35/kg milk $0.315/kg CP $0.1174/Mcal NEl Projected body weight 500 kg primiparous 600 kg multiparous
Analysis from dairy farm records 30 Wisconsin dairy farms Number of Income over Income over lactating Feed Cost Feed Cost cows (n=30) (no grouping) (3 groups) $/cow per year Mean 788 $2,311 $2,707 Minimum < 200 $697 $1,059 Maximum > 1,000 $2,967 $3,285 Increase of IOFC ($/cow per year) Between 7 and 52% Mean = $396 Range = $161 to $580 Cabrera et al., 2012
Acknowledgements This project is supported by Agriculture and Food Research Initiative Competitive Grant No. 2011-68004-30340 from the USDA National Institute of Food and Agriculture The author is grateful to Afshin Kalantari, Ph.D. Student, Dairy Science, University of Wisconsin- Madison for his support with the simulations
Thanks 2011 Wisconsin Milk Marketing Board, Inc.