Forage Quality for
Profitable Milk Production
Jim Linn, Professor Emeritus
Univ. of Minnesota
LACTATION RATION INGREDIENTS
% OF DM
FIBER
50
FORAGES
Physical & Chemical
Protein, Energy,
Carbohydrates, Minerals,
20
30
FORAGE, GRAIN OR
BYPRODUCTS
CONCENTRATES
• CORN
• PROTEIN
• MINERALS/ADDITIVES
Flexible
Nutrient needs and $ Ration
Feeds
Non-Fiber CHO
Starch
Protein
RDP & RUP
Minerals
Feed Cost (% of total)
Fat
4-7%
for 85 lb milk_
Feed
Min-Vit Additives
4 – 8%
2 – 5%
RD-Protein
RU-Protein
5 – 8%
20 – 25%
Byproducts
10%
Feed Cost/Cow/Day
Grain – Starch
15 – 20%
Forages
45 – 50%
$8.00 - $10.00
SHOULD YOU MAXIMIZE
FORAGE FEEDING?
Alfalfa/Grass Forage
$250 to $300/ton hay basis
Corn Silage – 35% DM
$55 - 85/ton – 40% starch
$50 – 70/ton – 30% starch
FORAGE QUALITY FACTORS IN
LACTATION RATIONS
FORAGE QUALITY MEASUREMENTS
Chemical
 Dry matter (DM)
 Ash
 Crude Protein
Physical
 peNDF
 PN State Particle
Separator (PSPS)
– True, Non Amm N, Sol
 NDF
 Lignin
 NFC (NSC)
– Starch
– Sugar
– Pectin
Digestibility
 NDFD
 Starch
Practical Application of
Forage Quality Variation
On Farms
Cows require Nutrients
Forage DM Consistency
McBeth et al. Ohio State U
Con = 55%F:45%C
UNB = same diet with 10% water added to forage
BAL = diet adjusted for decrease in forage DM
McBeth et al., 2012
Ohio State University
21 day treatment means
Item
Con
UNB
BAL
DMI, kg/d
24.0
24.1
23.9
Milk, kg/d
39.3
39.8
39.7
Fat, %
3.42
3.37
3.30
Monitoring Forage DM on Farms
• Determine Forage
DM - 2X/week
• Adjust ration
3 unit change in DM
• Establish protocol
Fiber Requirements for Lactating Dairy Cows
Good, Bad and Unknown
Chemical
Physical
Adapted from Varga - 2010
ISSUE - MIXED COMPOSITION OF NFC
Alfalfa
NDF – 36%
CP –
22%
Fat –
3%
Ash – 11%
NFC = 28%
Corn Silage
NDF – 42%
CP –
8%
Fat –
3%
Ash –
6%
NFC = 41%
Fiber (chemical) guidelines for lactating cows1.
Total
NDF
Lactating Cows
<100 days in milk
100 to 200 days in milk
>200 days in milk
1Assumes
Forage
NDF
ADF
---------- % of diet DM ----------
>28
>19
>18
29-32
20-22
>19
>32
21-24
>19
forage particle size is adequate and ground dry corn is
starch source.
Effect of Forage Fiber on Milk Production
Eastridge, OSU
DAIRY COW PERFORMANCE AND NDF DIGESTIBILITY
 As NDFD increases 1% unit:
– .4 lb DMI
– .55 lb FCM
– MSU, Oba and Allen
U of MN Study
Alfalfa Hay Dig NDF
Importance of forage quality

NDF concentration

NDF digestibility (NDFD)
Previous studies

Confounding NDF digestibility and
NDF concentration
Interest surrounding NDFD

TDN equation


(NRC, 2001)
RFQ
Determine the effect of alfalfa hay fiber
digestibility, compared within relatively
high and low NDF concentration hays
Alfalfa Hay Treatments
Treatment
Designations
NDF
concentration
In vitro 48-h
NDF digestibility
LH
LL
Low
Low
High
Low
HH
HL
High
High
High
Low
© 2011 Regents of the University of Minnesota. All rights reserved.
HAY LOT CORE SAMPLES
2 CORES PER BALE
Treatment
LH
LL
HH
HL
87.4
91.5
DM, %
93.8
93.0
NDF, %
37.2
36.4
41.7
40.8
IVNDFD1, % NDF
41.3
37.9
44.6
41.1
CP, %
21.4
22.5
20.1
20.8
NFC, %
28.8
24.0
24.0
25.9
RFV
163.1
168.7
138.2
143.4
RFQ
156.0
144.9
143.0
138.1
148-hour
in vitro NDF digestibility
© 2011 Regents of the University of Minnesota. All rights reserved.
MN - 15% of diet DM
Diet Ingredient Composition
LH
Treatment
LL
HH
HL
--------- % of diet (DM basis) ---------
Hay1
Corn silage
Corn
Grain Mix2
Roasted Soybeans
Molasses
125%
16.0
36.3
13.1
26.4
5.2
3.0
16.0
36.3
13.1
26.4
5.2
3.0
13.7
33.7
17.8
26.5
5.3
3.1
13.7
33.7
17.8
26.5
5.3
3.1
of LL hay fed as long-stem
2Grain
mix composition (air dry basis) = 34.3 % soybean meal, 22.9% DDGS, 3.8% blood
meal, 26.7% soybean hulls, 12.3% vitamins/minerals
© 2011 Regents of the University of Minnesota. All rights reserved.
MN - 15% of diet DM
Nutrient Composition of Diet1
LH
Treatment
LL
HH
HL
---------------------------- % of DM -------------------------
DM
59.8
60.1
61.3
60.5
CP
17.5
17.9
18.0
17.6
NDF
31.4
30.9
30.0
29.9
Forage NDF
21.6
21.0
19.7
19.6
3.3
3.4
3.5
3.4
NFC
41.4
41.2
42.9
43.0
NEL3X(Mcal/kg)
1.6
1.6
1.6
1.6
EE
1Analysis
conducted on individual diet ingredients
© 2011 Regents of the University of Minnesota. All rights reserved.
Materials and Methods
Hays
– Ground using AgriMetal tub
grinder
– LL treatment received 25% of
hay as long stem
Diets
– Fed as TMR (Data Ranger)
23
Hay Characterization-MN
LH
HH
LL
HL
© 2011 Regents of the University of Minnesota. All rights reserved.
MN - 15% of diet DM
Production Performance and
Body Weight (BW) Change
Treatment
LH
LL
HH
N=
15
16
12
12
DMI, kg/d
22.8
21.7
22.1
22.8
.77
Milk, kg/d
38.8
38.8
39.3
39.3
.99
3.5% FCM, kg/d
38.3
40.0
40.5
40.4
.59
1.7
1.9
1.9
1.9
.53
-20.8
-49.1
-37.8
-24.5
.29
FE, kg 3.5% FCM/kg DMI
BW change1,
1BW
kg
change = initial - final body weight
© 2011 Regents of the University of Minnesota. All rights reserved.
HL
Trt
--- p-value---
Part II.
US Dairy Forage Research Center
Alfalfa Hay = 30% of Diet DM
WI - 30% of diet DM
Nutrient Composition of Diet1
LH
Treatment
LL
HH
HL
---------------------------- % of DM -------------------------
DM
59.8
59.8
59.3
59.6
CP
17.4
17.4
18.7
18.1
NDF
28.6
28.0
28.7
28.6
Starch
24.6
24.5
24.4
24.5
1Analysis
conducted on individual diet ingredients
© 2011 Regents of the University of Minnesota. All rights reserved.
WI - 30% of diet DM
Milk Yield and Fat %
Treatment
LH
LL
HH
HL
Trt
--- p-value---
Milk yield, kg
Fat, %
43.9
45.2
46.5
45.3
<.18
3.4
3.5
3.4
3.4
<.75
© 2011 Regents of the University of Minnesota. All rights reserved.
Potential Reasons for
Lack of Response to Treatment
Small difference in NDF and in-vitro 48-h NDFD

NDF (4.5 % units)

NDFD (3.5 % units)
Physical Characteristics of hay

Particle size post grinding
© 2011 Regents of the University of Minnesota. All rights reserved.
CORN SILAGE – NDFD
Grain ~ 40-45% of WPDM
•Avg. 28% starch in WPDM
•Variable grain: stover
Stover= ~55-60% of WPDM
Leaves = 15% of DM
Stem = 20-25% of DM
Cob + Shank + Husk = 20% of DM
80 to 98% starch
digestibility
•Kernel maturity
•Kernel particle size
•Endosperm properties
Laurer, UWEX
40 to 70% NDFD
3.5%FCM, Kg/d
EFFECTS OF INCREASING CORN SILAGE NDFD ON 3.5% FCM
CORN SILAGE – 45% OF RATION DM
45
43
41
39
37
35
33
31
29
27
25
0%BMR
25%BMR
50%BMR
75%BMR
100%BMR
P=0.70
1
2
Silage
24 hr IVNDF, %
48 hr IVNDF,%
NDF, %
3
4
5
Week
0% BMR
36
54
45
6
7
8
100% BMR
41
62
44
U of MN
Fiber Requirements for Lactating
Dairy Cows
Physical
Particle size
FIBER – PHYSICAL OR EFFECTIVE
 Function
– Stimulates rumination
– Builds fiber mat in rumen
– Helps prevent acidosis and low milk fat
tests
Effective Fiber
(Penn State Separator Box)
Hay Characterization-MN
LH
HH
LL
HL
© 2011 Regents of the University of Minnesota. All rights reserved.
Hay Characterization- MN
Particle Size of Ground Hays
Monthly Analysis Using Penn State Forage Particle Separator
LH
HH
Upper, % = 26.9a
Upper, % = 14.6b
Middle, % = 16.6a
Middle, % = 23.1b
Lower, % = 33.3
Lower, % = 32.8
Bottom, % = 23.2a
Bottom, % = 29.5bc
LL
HL
Upper, % = 9.7b
Upper, % = 23.5a
Middle, % = 22.8b
Middle, % = 21.5b
Lower, % = 34.0
Lower, % = 30.2
Bottom, % = 33.4b
Bottom, % = 24.8ac
Recommended Percent of Feed Particles
Penn State Particle Size Box
Top
Box
Feed
Middle Bottom
Box
Box
----------------% of total---------------
Haylage
10-20
40- 60
< 40
Corn silage (3/4 inch
TLC & processed)
10-20
50-60
<30
Corn silage (1/4 inch
TLC & unprocessed)
<5
>50
<50
5-15
40-50
<50
TMR
© 2011 Regents of the University of Minnesota. All rights reserved.
Particle Size Feed and Feed Refusals
50 free stall herds – MN
2nd screen >8 mm
3rd screen >1.18 mm
Top screen >19 mm
Pan <1.18 mm
Fed
3 hr
6hr
9hr
24hr
Endres et al. 2010 JDS
Shredlage Study – Univ of Wisconsin
–Shaver et al.
Shredlage
Photos provided by Kevin Shinners, UW Madison, BSE
KP
PENN STATE SEPARATOR BOX (AS-FED
BASIS)
Samples obtained during feed-out from the silo bags
Screen, mm
Shredlage
KP
19
31.5%
5.6%
8
41.5%
75.6%
1.18
26.2%
18.4%
Pan
0.8%
0.4%
PENN STATE SEPARATOR BOX (AS-FED
BASIS)
TMR Samples
Screen, mm
Shredlage
KP
19
15.6%
3.5%
8
38.2%
52.9%
1.18
38.9%
35.8%
Pan
7.3%
7.8%
FEED SORTING – PSU SEPARATOR
BOX
% of Predicted Intake
Shredlage
KP
P<
19
99.3
99.5
0.72
8
99.7
99.8
0.66
1.18
100.1
99.7
0.09
Pan
102.1
101.7
0.54
Screen, mm
3.5% FCM YIELD BY WEEK
102
*
101
Lb/cow/day
100
*
**
* P < 0.10
** P < 0.01
99
98
97
Shredlage
96
KP
95
94
Shredlage
KP
2
100.1
100.9
4
6
101
99.4
98.1
96.9
Week on Treatment
8
99.8
95.4
Week × Treatment Interaction (P < 0.03)
U. of WI – Shaver et al
Alfalfa vs. Grass Hay in Lactation Rations
HAY NUTRIENT COMPOSITION1
Alfalfa
Orchardgrass
--------------- % DM--------------
NDF
ADF
CP
NDICP
Lignin
Ca
K
1Analysis
40.8
31.3
21.7
3.49
4.66
1.86
2.42
conducted on weekly grab samples of chopped hays.
© 2011 Regents of the University of Minnesota. All rights reserved.
59.7
32.7
16.4
7.04
2.36
0.43
3.19
Digestion Kinetics of Hays1
70.8%
52.0%
IVNDFD
Alfalfa
Rate = 5.20% per hr
Potential = 55.5%
Orchardgrass
Rate = 4.60% per hr
Potential = 78.7%
1Incubation
time points = 6, 12, 18, 24, 32, 48, 72 and 96 hr.
Ingredient Composition of
Alfalfa Diets
Alfalfa Hay, % of Diet DM
15
20
25
30
Corn silage
35.0
35.0
35.0
35.0
35.0
Alfalfa hay1
15.0
20.0
25.0
30.0
35.0
Corn, ground
20.6
17.7
15.0
11.8
Soybean meal, 44%
Protein/mineral mix2
6.68
18.0
4.74
18.0
2.78
18.0
0.88
18.0
35
7.60
0.00
18.0
Molasses mix
4.00
4.00
4.00
4.00
4.00
Calcium carbonate
0.56
0.34
0.00
0.00
0.00
Monocalcium phosphate
0.16
0.20
0.24
0.30
0.40
1Alfalfa
hay ground using a vertical mixer prior to feeding.
2Protein/mineral
mix composition (air dry basis) = 30.0% soybean hulls, 30% soypass, 18.4% corn
distillers grains, 5.0% bloodmeal, 7.5% energy booster, and 8.9% minerals/additives.
© 2011 Regents of the University of Minnesota. All rights reserved.
Ingredient Composition of
Orchardgrass Diets
Orchardgrass Hay, % of Diet DM
10
15
20
25
30
Corn silage
35.0
35.0
35.0
35.0
35.0
Orchardgrass hay1
10.0
15.0
20.0
25.0
30.0
Corn, ground
21.5
17.7
13.8
10.1
Soybean meal, 44%
10.3
Protein/mineral mix2
18.0
9.24
18.0
8.18
18.0
7.06
18.0
6.06
6.00
18.0
Molasses mix
4.00
4.00
4.00
4.00
4.00
Calcium carbonate
1.14
1.10
1.06
0.84
0.94
1Alfalfa
hay ground using a vertical mixer prior to feeding.
2Protein/mineral
mix composition (air dry basis) = 30.0% soybean hulls, 30% soypass, 18.4% corn
distillers grains, 5.0% bloodmeal, 7.5% energy booster, and 8.9% minerals/additives.
© 2011 Regents of the University of Minnesota. All rights reserved.
PHYSICAL CHARACTERISTICS OF HAYS1
Alfalfa
Orchardgrass
-----% Particle Retained (as-is) ----Top
16.7a
28.5x
Second
27.8b
30.0x
Third
28.6b
28.6x
Bottom
26.9b
13.1y
1Analysis
conducted on weekly grab samples of chopped hays using the Penn State Particle
Separator. Statistical analysis conducted within forage species.
© 2011 Regents of the University of Minnesota. All rights reserved.
Physical Characteristics of Alfalfa Diets and Refusals
Particles Retained on Top Screen of PSPS1
Particles retained (%, asis)
% Refusal - % Diet
Alfalfa Hay:
15: + 2.2% units
20: + 3.8% units
25: + 5.8% units
30: + 9.8% units
35: + 5.3% units
Alfalfa Hay, % of Diet DM
1PSPS
= Penn State Particle Separator. Analysis conducted on weekly grab samples using the Penn State
Particle Separator.
Particles retained (%, asis)
Physical Characteristics of Orch. Diets and Refusals
Particles Retained on Top Screen of PSPS1
% Refusal - % Diet
Orchardgrass Hay:
10: + 2.7% units
15: + 0.4% units
20: + 2.5% units
25: + 5.5% units
30: + 6.6% units
1PSPS
Orchardgrass Hay, % of Diet
DM
= Penn State Particle Separator. Analysis conducted on weekly grab samples using the Penn State
Particle Separator. Statistical analysis conducted across diets for diet and refusal.
Dry Matter Intake (DMI)
Common Linear Fit:
slope = -0.81, r2 = 0.47, P =
0.02
Slope
ALF
= Slope
ORCH
For regressors:
Hay, %
Dietary NDF, %
Forage NDF, %
Hay NDF, %
3.5% Fat Corrected Milk (FCM) Yield
Individual Linear Fits:
ALF: slope = -2.68, r2 = 0.71, P = 0.05
ORCH: slope = -1.02, r2 = 0.34, P = 0.18
TAKE HOME POINTS
1. Important applied on farm forage quality
measures
NDF, NDFD and forage DM
2. Chemical fiber measures
NDF
NDF - Forage related to milk production
NDFD – ranking within forage species
NFC – know composition
TAKE HOME POINTS
3. Physical fiber
• Important for rumen function and
rumination
• Particle size forages and TMR
TMR – rumen health
Refusal – sorting
• Current guidelines good, but evaluate
with changing forage types (legume vs.
grasses) and corn silage processing.
“FEEDBACK IS THE BREAKFAST OF CHAMPIONS”
ONE MINUTE MANAGER BY KEN BLANCHARD
National Champions 41-0
More frequent feedback (forage analysis):
provides more accurate analysis and
promotes higher quality performance
QUESTIONS?
Thank you