FEED ADDITIVES IN DIETS OF
TRANSITION DAIRY COWS
José Eduardo P. Santos
Veterinary Medicine Teaching and Research Center
School of Veterinary Medicine
University of California - Davis
Objectives
• Discuss the metabolic and endocrine effects of feed
additives during the transition period
• Potential impact of the use of feed additives during
transition on performance and incidence of metabolic
disorders in dairy cows
Rumen Fermentation
Propionate
Microbial
Protein + NH3
CO2 +
CH4 +
CHO
Protein
H2
Pyruvate
Glucose
Acetate +
Butyrate
Effect of Ionophores on Rumen Bacteria (Gram +)
• Extracellular
•
• H+
•
Intracellular
ATP
H+
ADP
• H+
• K+
M
H+
K+
M
Na+
H+
• Na+
• H+
Results of Ionophore Use
• Reduces Gram + population:
– Proteolytic and amilolytic bacteria
• Decreases proteolysis ----> Greater flow of nonammonianonmicrobial nitrogen to the duodenum
• Reduces lactate producing bacteria: Streptococcus bovis
and Lactobacillus spp.
• Increases molar concentration of propionate
• Reduces CH4 concentration ---> Less energy loss
Why Ionophores Would Benefit Transition Cows?
• Improves efficiency of energy metabolism:
– More propionate
– More glucose
– Less BHBA
– More insulin
– Less lipid mobilization
• Lower incidence of subclinical ketosis
• Reduces the risk for ruminal acidosis and bloat
• Increases the flow of true protein (It may not change total
protein flow because of the negative impact on microbial N)
Effect of Sodium Monensin on Metabolic Parameters of Dairy Cows
Item
Treatment
BHBA,
mg/dl
Glucose,
mg/dl
NEFA
Reference
Abe et al.
(1994)
At calving
C
M
23.70
11.74**
55.1
58.3*
3.90
3.75
Prepartum
C
150 mg/d
300 mg/d
450 mg/d
14.91
13.91
13.90
14.31
58.6
58.9
61.0**
60.31*
0.46
0.38**
0.40
0.39*
Wade et al.
(1996)
Prepartum
C
M
15.24
12.46*
65.1*
62.8
0.438
0.581
Stephenson
et al. (1994)
Postpartum
C
M
5.15
4.34
63.3
65.5
NA
NA
Phipps et al.
(1997)
Effect of Monensin on Performance of Dairy Cows
Monensin, mg/kd
0
8
16
24
215
210
216
217
Prepartum
11.1
11.0
10.9
10.5a
Postpartum
19.8
20.0
19.4 a
19.2 a
Milk, kg/d
29.3
30.3 a
30.2
30.4 a
Milk fat, %
3.66
3.61
3.52 a
3.42 a
Milk protein, %
3.15
3.16
3.14
3.12 a
No. cows
DMI, kg/d
Adapted from Symanowski et al. (1999) and Wagner et al. (1999)
a
Different from the control (P < 0.05)
Effect of Monensin on Reproductive Performance of Cows
Beckett et al. (1998)
1.1
1.01
0.94
1
0.9
444/530
438/526
0.8
0.7
0.6
271/497
283/486
0.5
0.4
0.3
Monensin
Control
FSC
Preg. Rate
Relative risk
Gluconeogenic Precursors
• 4 major sources:
– Propylene glycol
– Calcium propionate
– Sodium propionate
– Glycerol
• Poorly fermented in the rumen
• Calcium propionate is also a source of Ca
Effect of Propylene Glycol on Rumen Fermentation
Molar concentration
Acetate Propionate
Total
A:P
4.1*** Grummer
1.6 et al. (1994)
Control
296 ml/d
69.1
51.6
16.9
33.5**
100.1
99.9
592 ml/d
54.0
26.9**
100.1
2.0
887 ml/d
54.0
25.4**
100.3
2.0
Control1
64.6
19.1
58.9**
3.4
2,347 g/d
57.0
30.3***
45.3
1.9
1
In vitro incubation
Emery et al.
(1964)
Effect of PG Dosage on Blood Metabolites of Feed Restricted Heifers
PG dose (d 12)
0 ml/d
296 ml/d
592 ml/d
Glucose, mg/dl
75.2
80.0
81.1
82.0
***
Insulin, IU/ml
13.0
17.7
18.2
19.8
**
BHBA, mg/dl
8.5
4.8
3.6
3.9
***
NEFA, mEq/L
0.746
0.425
0.332
0.282
***
Grummer et al. (1994)
887 ml/d Contrast
Effect of Method of PG Delivery on Blood Metabolites of Feed
Restricted Cows
PG dosage and delivery
Control
340 O
340 C
Glucose, mg/dl
65.8
67.8
68.8
66.5
Insulin, IU/ml
16.6
33.0
31.9
24.0
***
NEFA mEq/L
0.183
0.154
0.155
0.161
**
BHBA, mg/dl
13.7
13.6
14.4
14.2
Christensen et al. (1997)
340 TMR Contrast
Effect of PG Delivery Method on Rumen Fermentation
PG dosage and delivery
VFA
Control
340 O
340 C
Acetate
67.0
59.8
59.8
62.2
***
Propionate
18.3
25.4**
25.4**
22.6
***
Butyrate
8.5
8.5
8.5
8.5
A:P
3.8
2.3**
2.4**
2.8
Christensen et al. (1997)
340 TMR Contrast
***
Effect of PG on Performance and Blood Metabolites of Cows
Item
Treatment
Milk,
kg/d
Insulin,
IU/ml
Glucose, BHBA, NEFA, Reference
mg/dl
mg/dl mEq/L
0 ml/d
300 ml/d
24.5
27.0
NA
NA
65.4
66.0
6.73
4.80
0.415
0.384
Fonseca et
al. (1998)
0 ml/d
500 ml/d
NA
NA
6.5
11.1
53.0
59.2
NA
NA
0.386
0.290
Miyoshi et
al. (1995)
0 ml/d
1,000 ml/d
33.2
32.6
0.354
0.679***
Low
High***
Low
High
0.403** Studer et
0.234 al. (1993)
Effect of Propylene Glycol on Liver Lipids and TG
33
30
27
24
21
18
15
12
Studer et al. (1993)
17
% (DM basis)
% (DM basis)
Studer et al. (1993)
14
11
8
5
d +1
Control
d +21
PG 1L/d
2
d +1
Control
d +21
PG 1L/d
Kg/d
Effect of PG on Transition Cow Performance
Formigoni et al. (1996)
P > 0.15
40
39
38
37
36
35
34
33
32
31
30
Milk
4% FCM
Control
PG 300 g/d
• PG had no impact on milk
composition
and
plasma
insulin
• PG increased IGF-I, plasma
cholesterol and decreased
MUN and NEFA
Effect of Ca Propionate Prepartum on Blood Metabolites of Dairy Cows
Item
Tretment
Breed Ca, mg/dl Ca, mg/dl
(24hs)
(10 d)
BHBA
mg/dl
NEFA, Reference
mEq/L
Control
4 tubes
H
H
6.87
7.23
7.95
8.25
13.1
10.6
NA
NA
Goff et al.
(1996)
Control
6 tubes
H
H
7.34
7.98
8.50
8.57
13.5
13.2
0.79
0.81
Goff et al.
(1996)
Control
4 tubes
J
J
6.02
7.23**
8.74
8.30
6.9*
4.4
0.74*
0.51
Goff et al.
(1996)
Control
110 g Ca +
454 g PG
H
H
4.30
5.30***
4.90
4.80
NA
NA
1.39** Higgins et
0.85 al. (1996)
Niacin
Blood Compartment
-
Adipose Tissue
Niacin
HSL
Triacylglycerol
Diacylglycerol
Monoacylglycerol
NEFA
Effect of Niacin on Performance of Dairy Cows
Increment over control diet
Diets
Studies,
No.
Milk,
kg/d
Fat,
%
Protein,
%
Regular
19
+ 0.76
+ 0.165
+ 0.06
Supplemented with fat
5
- 0.36
- 0.044
+ 0.10
Hutjens (1991)
Effect of NFC and Niacin on Prepartum DM and Energy Intakes
Diet
LNFC
HNFC LNFC + N HNFC + N
Niacin
effect
DMI, kg/d
10.2
13.0
10.1
12.6
No
NEL intake,
Mcal/d
EB, Mcal/d
13.5
21.2
13.5
20.4
No
0.10
7.39
-0.24
6.76
No
Minor et al. (1998)
Effect of Prepartum Diet on Plasma and Liver Metabolites of
Transition Cows
Diet
LNFC
HNFC
LNFC + N
HNFC + N
Niacin
effect
Glucose, mg/dl
59.4
62.2
61.0
64.0
No
NEFA, M
378
293
389
225
No
BHBA, mg/dl
11.4
8.0
11.0
7.8
No
Glycogen, %
4.5
6.8
4.5**
8.2
No
TG, %
5.0
4.1
7.9*
4.3
No
Hepatic
Minor et al. (1998)
Effect of Niacin During Transition on Performance of Dairy Cows
DMI, kg/d
Milk
FCM
Fat
Prep.
Postp.
Control
Fat
11.7
12.1
21.8
21.6
38.4
42.0
36.3
39.3
3.14
3.15
3.00
2.87
AVG
11.9
21.7
40.2
37.8
3.15
2.94
Niacin
Niacin+Fat
12.1
11.3
19.8
21.3
36.3
41.3
34.5
38.2
3.19
3.12
2.87
2.89
AVG
11.7
20.6
38.8
36.4
3.16
2.88
Skaar et al. (1989)
kg/d
Protein
%
Ruminally Protected Amino Acids
• AA can be used as gluconeogenic precursors
• Enhance oxidation of fatty acids by the hepatic tissue
• Enhance VLDL synthesis and secretion
• Reduce ketogenesis
• Supply limiting amino acids for milk and milk protein
synthesis
Effect of Supplemental Methionine on Hepatic Metabolism
Item
Treatment
Hepatic
TG, mg %
NEFA,
mEq/l
Glucose, Reference
mg/dl
Control
23.0
0.270
61.2
13 g Met
20.0
0.346
59.4
Control
12.7
0.820
58.0**
13 g Met
15.4
1.076**
50.3
Bertics and
Grummer, 1998
Bertics and
Grummer, 1997
Effect of Methionine or Methionine + Lysine on Metabolism
Item
Treatment
Hepatic TG, mg %
NEFA,
mEq/l
Glucose,
mg/dl
wk 1
wk 3
Control
28.6
26.7
0.399
80.8*
10.5 g Met
24.8
24.6
0.374
78.3
10.2 g Met. + 16 g Lys
35.6
27.7
0.461
73.8
Control
21.5
24.2
0.377
80.1*
10.5 g Met
24.8
24.9
0.447
79.0
10.2 g Met. + 16 g Lys
26.2
25.5
0.431
74.1
16 % CP
18.5 % CP
Socha (1994)
• Bauchart et al. (1998) observed that rumen-protected lysine
reduced hepatic triglyceride content
• Review by Garthwaite et al. (1998) - 6 studies
– Rumen protected Lys and/or Met supplemented pre- and
postpartum
•  DMI 0.5 kg/d,  milk yield 1.5 kg/d,  milk protein
yield 79 g/d, and  milk fat yield 85 g/d
– 2 studies, supplemental
performance
Met
was
detrimental
to
Yeast Culture
• Possible reasons for feeding Saccharomyces cerevisiae in
transition diets
–
–
–
–
–
Increase rumen pH (Selenomonas ruminatium)
Stimulate the growth of fiber digesting bacteria
Increase NDF digestibility
Reduce the depression in DMI immediately before calving
Improve DMI postpartum
Effect of Saccharomyces cerevisiae on Performance of Transition Cows
Treatment
Prepartum
DMI, kg/d DMI, % BW BCSC BWC, kg/d Reference
Control
Yeast, 57g/d
10.97
10.79
1.52
1.48
-0.08**
-0.01
Control
Yeast, 15g/d
12.10
12.10
1.71
-0.06
1.70
0.02
Postpartum
0.19
0.36
Robinson
(1997)
1.09
1.06
Soder and
Holden (1999)
DMI, kg/d DMI, % BW Milk, kg/d Fat, %
Control
Yeast, 57g/d
17.38
17.62
2.73
2.78
34.09
34.65
4.17
4.33
Robinson
(1997)
Control
Yeast, 15g/d
21.95
22.90
3.41
3.54
40.70
41.05
4.07
3.92
Soder and
Holden (1999)
Effect of Saccharomyces cerevisiae on transition cow performance
(Robinson and Garrett,1999)
P < .28
42
40.4
38.6
40
•
Feeding YC from d -28 to d 56
had no effect on DMI, DMI as %
BW, BW and BCS changes, and
NEL of diets during the pre- and
postpartum periods
•
Feeding YC had no impact on
concentration and yields of fat,
protein,
and
lactose
of
primiparous and multiparous
cows
38
36
kg/d
34
32
30
P < .09
28
25.4
27.8
26
24
22
20
18
Primiparous
Control
Multiparous
Yeast Culture
Hypocalcemia (clinical or subclinical)
 Smooth Muscle Function
 Rumen and GI Tract Motility
 RP
 DMI
 DA
 Ketosis
 Milk Production
 Uterine Motility-Immunity
 NEB
 Involution
 Metritis
 Fertility
Bone Resorption
Diet
PTH/Vit D ++
Calcitonin 
Hypercalcemia 
Intestine
Vit. D ++
Extracellular Ca Pool
(8 to 10 g)
Plasma Ca Pool
2.5 to 3.0 g
Milk
20 - 80 g/d
Fetal Bone
2 - 10 g/d
Fecal Loss
6 - 10 g/d
PTH and
Vit D
Urinary Loss
0.25 - 1.0 g/d
Acidogenic Salts
• High chloride and sulfate salts
– CaCl2, NH4Cl; MgCl, MgSO4, CaSO4, (NH4)2SO4
– HCl
• Acidify the blood by increasing H+ absorption
• S is poorly absorbed --> It is not a good acidifier
Lumen GI Tract
Intracellular and
Cell Membrane Intravascular
Spaces
SO4-2
-
Cl-
H+
-
 H+
 pH
 HCO3-
Strategies for Prevention of Hypocalcemia
DCAD < 250 mEq/kg
 PTH Receptor
Sensitivity
Addition of Anions
DCAD > 250 mEq/kg
 Calcitropic
Hormones
Low Ca diets < 20 g/d
Vit. D Analogues
 Passive
Absorption
Ca Gels
Effect of Dietary K and Ca on Ca Homeostasis of Dairy Cows
Dietary K
Diet
1.1 %
2.1 %
3.1 %
0.5% Ca
Milk fever
0/10
4/11
8/10
Hypocalcemia
9/10
11/11
10/10
Blood Ca, mg/dl
6.57
6.07
5.22
Milk fever
2/10
6/9
3/13
Hypocalcemia
9/10
9/9
4/3
Blood Ca, mg/dl
6.90
5.27
6.39
1.5% Ca
Goff and Horst (1997)
Conversion Factors from % to mEq/kg on a DM Basis
Atomic wt
(g)
Charge
Equivalent wt
(g)
Factor
Na+
23.0
1 (+)
23.0
435
K+
39.1
1 (+)
39.1
256
Cl-
35.5
1 (-)
35.5
282
S2-
32.1
2 (-)
16.05
623
Equations to Calculate DCAD
• DCAD mEq/kg ={(0.38 Ca + 0.3 Mg + Na + K) - (Cl + 0.6 S + 0.5
P)}
– (NRC’s coefficients)
• DCAD mEq/kg ={(0.15 Ca + 0.15 Mg + Na + K) - (Cl + 0.2 S + 0.3
P)}
– (Goff’s coefficients)
• DCAD mEq/kg = {(Na + K) - (Cl + S)}
– Assumes equal rate of absorption for all strong ions
How to Use Them
• Step 1
• Analyze all feed components for their mineral content
– Na, K, S, Cl, Ca, P, and Mg
• Select forages and ingredients with low K and Na content
– Grain silages, low K alfalfa (mature), brewers grains,
beet pulp without molasses, citrus pulp
• Basal diet DCAD < 250 mEq/kg
• Step 2:
– Adjust mineral content
• Provide Mg to achieve 0.4% diet DM
– MgSO4, MgCl, MgO
• Increase S up to 0.35 to 0.4 %
– CaSO4
– S > 0.4% may cause PEM and may interfere with Cu and Se
• Keep P at 0.35 to 0.4%
– High P intake (> 80g/d) may cause milk fever
• Step 3:
– Acidify the diet
• Keep K as low as possible (K < 1.2%)
• Keep Na as low as possible (Na < 0.15)
• Increase Cl
– CaCl2
– Keep Cl < 0.8%, but high enough to lower urine pH
• Adjust Ca content to 1.0 to 1.2%
– Ca Propionate or CaCO3
Mineral Profile of a Close Up Diet
Mineral
Na
K
S
Cl
Ca
P
Mg
% Diet (DM)
0.1
< 1.2
0.35
0.5 – 0.7
1.0 – 1.2
0.4
0.4
• Dietary DCAD should be:
– Multiparous cows = - 50 mEq/kg
– Primiparous cows = 0 mEq/kg
• Monitor urine pH
– Urine pH should be between 5.8
and 6.8
Addition of Anions and Urine pH
9
8
pH
7
6
5
4
3
0.5
1
1.5
2
2.5
3
3.5
4
Anions (Eq)
4.5
5
5.5
6
6.5
7
Conclusions
• Ionophores (Monensin):
– Prepartum: 30 ppm and Postpartum: 10 - 15 ppm
• PG and Ca Propionate may be used in the concentrate or as an oral
drench. Consider Ca Prop. when using anionic salts
• Niacin: Controversial results
• Lipotropic agents and Yeast: Not recommended
• Acidogenic salts: Highly recommended when hypocalcemia is a
concern
• RP AA: positive effects on milk protein content and yields of milk
and milk protein when supplemented pre- and postpartum