Measuring Cow Efficiency in the Herd
Ryon S. WalkerLivestock Consultant
Noble Research Institute
Does Cow Size Matter?
• If you don’t tag at birth, you don’t know who belongs to who, and you don’t weigh your cows or calves, THEN NO!
– How can you make change if you don’t know what to change!
• If you do all the above, THEN YES!
Guess the Weight
Cow 097 body weight – 1510 lbs• Closest guess – 1497 lbs• Range – 800 to 2050 lbs• 62% missed it by 200 lbs or more
• 89% guessed too low• 11% guessed too high
Guess the Weight
Cow 4016 body weight – 1225 lbs• Closest guess – 1225 lbs• Range – 812 to 1700 lbs• 34% missed it by 200 lbs or more
• 75% guessed too low• 25% guessed too high
Can’t Manage What You Don’t Measure!!!
NASS, Federally Inspected Slaughter Report
U. S. Meat Animal Research Center (MARC) evaluation of current breed
genetics
Breed Mature Cow Size
Simmental 1,353 pounds
Hereford 1,348 pounds
Angus 1,342 pounds
Charolais 1,339 pounds
Limousin 1,330 pounds
Gelbvieh 1,282 pounds
All cows are four-year olds at a body condition score of 5.
Adapted from American Gelbvieh Association
What Happened the Last 30 Years!
• Feedlots were putting pressure on faster gaining heavier calves going in and out of the feedlots = more lbs of “Closely Trimmed Retail Cuts”!
• Introduction of more continental bloodlines
• High correlation between growth and mature size, and carcass weights and mature size (.80 and .76; Bullock et al., 1993)
Dickinson Research Extension Center (NDSU)
• Mature cows (ages 5-9)
Kris Ringwall, Beef Talk, Dickenson Extension Research Center, Dickenson, ND, NDSU
Avg. Cow Wt - lbs Avg. Weaning Wt - lbs % of Mature Body Weight Weaned
1,272 lbs 602 lbs 47 %
1,571 lbs 603 lbs 42 %
NW MN Beef Improvement Program
1297
1490
579 596
0
200
400
600
800
1000
1200
1400
1600Light Cows 1050-1385
Heavy Cows 1388-1918
(12 Beef Herds [914 hd] Avg Mature Wt. = 1386 lbs)
17 lbs. difference
Ages 4 ½ and up
(Walker et al., 2011)
NW MN Beef Improvement Program
1238 1380 142 lbs
639 633 -6 lb
1414 1694 280 lbs
598 623 25 lbs1268 1482 214 lbs
620 623 3 lbs
1294 1447 153 lbs
563 595 32 lbs
1250 1431 181 lbs
498 516 18 lbs
1269 1476 207 lbs
586 612 26 lbs
1261 1431 170 lbs
516 516 0 lb
1353 1519 166 lbs
526 547 21 lbs
1369 1533 164 lbs
623 627 4 lbs
1260 1398 138 lbs
544 585 41 lbs
1257 1410 153 lbs
574 599 25 lbs
1319 1488 169 lbs
623 640 17 lbs
Hill Farm Research Station, LSU
• Mature cows (ages 5-9)
Avg. Cow Wt - lbs Avg. Weaning Wt - lbs % of Mature Body Weight Weaned
1,185 lbs 488 lbs 41 %
1,343 lbs 515 lbs 38 %
Cow weight difference - 158 lbsCalf weight difference - 27 lbs
Dean Lee Research Station, LSU
• Mature cows (ages 5-9)
Avg. Cow Wt - lbs Avg. Weaning Wt - lbs % of Mature Body Weight Weaned
1,177 lbs 581 lbs 49 %
1,342 lbs 585 lbs 44 %
Cow weight difference - 165 lbsCalf weight difference - 4 lbs
Distribution of Cow Weight within Herds
750 950 1150 1350 1550 1750 1950
Herd 1
Herd 4
Herd 3
Herd 2
Herd 6
Herd 7
Herd 5
Herd 8
Herd 9
Herd 10
Herd 12
Herd 11
Producing 20 Peak Milk Production - NRC, 1996
0
5
10
15
20
25
30
35
Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec
Dry
Ma
tte
r In
tak
e,
lbs
Dry Matter Intake Requirements for Maintenance
1000 lbs
1200 lbs
1400 lbs
Cal
vin
g
Daily Intake Based on Cow Size
24.927.3
0
5
10
15
20
25
30
35
40
Light Heavy
DMI
POST-WEANING
Light Group - cow = 1221 lbsHeavy Group - cow = 1385 lbs
2.4 lbs
For every 100 lb increase in BW, 1.5 lb increase in DM intake.
Daily Intake Based on Cow Size
3536.8
0
5
10
15
20
25
30
35
40
Light Heavy
DMI
LACTATION
Light Group - cow = 1200 lbsHeavy Group - cow = 1369 lbs
1.8 lbs
For every 100 lb increase in BW, 1.1 lb increase in DM intake.
Average Daily Temp & Average Daily Dry Matter Intake for low and high RFI
0
10
20
30
40
50
60
70
80
90
11-Apr 21-Apr 1-May 11-May 21-May 31-May 10-Jun
Mean Temp
Low RFI
Avg. RFI
High RFI
Low RFI (1286 lbs) – 31.97 avg. daily DMI
High RFI (1288 lbs) – 39.42 avg. daily DMI
Heifer DMI Based on Dam BW Group
1212
1378
604 633
0100200300400500600700800900
100011001200130014001500
Light Heavy
BW, lbsDam
Heifer
15.6 16.9
3536.8
0
5
10
15
20
25
30
35
40
Light Heavy
DMI, lbsDam
Heifer
(P = 0.42)
Positive correlation between dam BW and subsequent heifer:• Heifer BW (r = 0.54)• BW gain (r = 0.31)• DMI (r = 0.42)• Frame Score (r = 0.58)
Does Cow Efficiency Matter?
U.S. Cow Herd Forage DM Requirements
Forage DM Requirement
50
100
150
200
250
1975 1980 1985 1990 1995 2000 2005
Forage DM
Tons DM(1,000,000)
Cow Inventory Decline in the U.S.
Number of Producing Beef Cows
25.0
30.0
35.0
40.0
45.0
50.0
1975 1980 1985 1990 1995 2000 2005
Head (1,000,000)
Cow Inventory
Forage Dry Matter Required to Support the Beef Cow Herd
Cow Inventory and Forage DM Requirement
50
100
150
200
250
1975 1980 1985 1990 1995 2000 2005
Tons DM(1,000,000)
25.0
30.0
35.0
40.0
45.0
50.0
Head (1,000,000)
Forage DM Cow Inventory
Why is the forage requirement the same for 13 million fewer cows?
Because we have made the cows bigger and asked them to do more!
Positive Feed Efficiency Correlations
• Dam BW and Offspring Heifer BW (Walker et al., 2015) 0.54
and Offspring Heifer DMI (Walker et al., 2015) 0.42
• Heifer DMI on forage then on grain (Cassady et al., 2016) 0.58
• Heifer RFI on forage then on grain (Cassady et al., 2016) 0.40
• Repeatability of RFI as a Heifer and later a Cow 0.51• 62.2% remained in same classification
• 37.8% changed classification• (Morgan et al., 2010)
• Pre- vs Post-pubertal RFI remaining the same (Loyd et al., 2011) 0.48
• Repeatability of RFI as Heifer and later as 3 yr old Cow 0.13• (Black et al., 2013)
• Bigger calves – means bigger cows
• Smaller cows – means smaller calves but more cows
• IDEAL – smaller cows with bigger calves
So What Do We Want?
X X X
What do we Want in a Cow?
• Forage Efficiency 50
• ↑ Pounds of Product 20
• High Fertility 20
• Moderate Size 10
Feed Efficiency
Hill Farm Research Station Cow Production and Feed Efficiency Data!
Dam Light BW Group Dam Heavy BW Group
Trait Light Calf WW Heavy Calf WW Light Calf WW Heavy Calf WW
Calf Adj. WW 485 540 507 560
Dam DMI 34.5 35.6 36.2 37.8
Dam BW 1204 1195 1345 1391
Feed Efficiency
Hill Farm Research Station Cow Production and Feed Efficiency Data!
Dam Light BW Group Dam Heavy BW Group
Trait Light Calf WW Heavy Calf WW Light Calf WW Heavy Calf WW
Calf Adj. WW 485 540 507 560
Dam DMI 34.5 35.6 36.2 37.8
Dam BW 1204 1195 1345 1391
Small Cow – Heavy Calf versus Big Cow – Light Calf• Small cows weigh 150 lbs less• Small cows eat 0.6 lbs DM/day less• Small cows wean 33 lbs more
$8.76
$52.80
Feed Efficiency
Hill Farm Research Station Cow Production and Feed Efficiency Data!
Dam Light BW Group Dam Heavy BW Group
Trait Light Calf WW Heavy Calf WW Light Calf WW Heavy Calf WW
Calf Adj. WW 485 540 507 560
Dam DMI 34.5 35.6 36.2 37.8
Dam BW 1204 1195 1345 1391
Small Cow – Heavy Calf versus Big Cow – Heavy Calf• Small cows weigh 200 lbs less• Small cows eat 2.2 lbs DM/day less• Small cows wean 20 lbs less
$32.10
- $32.00
What’s Our Goal?
To Produce:
• Little Cows with Little Calves
• Little Cows with Big Calves
• Big Cows with Little Calves
• Big Cows with Big Calves
What do we Need to Measure?
• Who Belongs to Who 30
• Cow Size 25
• Calf Weaning Weight 20
• Body Condition Score 15
• Pregnancy Rates 10
• Economics 5
Minnesota - Cow BCS and calf weaning weight
27 lb diff in weaning wt.
267 lb diff in true cow wt.
Minnesota Beef Herds
Hill Farm - Cow BCS and calf weaning weight
0
200
400
600
800
1000
1200
1400
4.6 BCS 5.2 BCS 6.1 BCS
Avg AdjCow Wt
Avg TrueCow Wt
Avg WWWt
10 lb diff in weaning wt.
92 lb diff in true cow wt.
Minnesota Beef Herds
Adjusting for BCS
How do I estimate the weight of a 1300 pound cow at a BCS 5 if she is a BCS 6?
1300 ÷ (SBW, percent of CS 5 for the CS in question)
So,1300 ÷ 1.08 = 1203 pounds
Selection based on an Economic Ranking System
Breakeven avg. adjusted mature cow wt. & avg. adjusted 205 day calf weaning wt.
Economic Value Ranking Individual cow cost difference + individual calf cost difference
Cow Cost Differences (avg. herd adjusted cow BW – individual adjusted cow BW) x diff DMI/lb x $/lb hay x 210 days feeding
Calf Cost Differences (individual adjusted 205 d calf wt. – avg. herd adjusted 205 d calf weight) * $/lb
Road Blocks
• Factors affecting production efficiency:– Breed– Genetics– Dam age– Forage Quality– Weather
• Not all producers have a set of scales.
• Not all producers:– Tag calves and pair up– Collect birth dates– Collect birth weights
What We Learned!
• Our cows have gotten bigger.
• Approximately 30% of herds do not wean bigger calves from bigger cows.
• Differences in DMI exist based on cow size.
• Moderate correlation with dam BW and multiple offspring growth traits, such as DMI.
• We are not good guessers at cow body weight.
QUESTIONS?