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?