FEED ADDITIVES IN DIETS OF TRANSITION DAIRY COWS

José Eduardo P. Santos

Veterinary Medicine Teaching and Research Center School of Veterinary MedicineUniversity 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

CHOProtein

MicrobialProtein + NH3

Glucose

Pyruvate

Propionate

Acetate + Butyrate

CO2 + CH4 +

H2

Effect of Ionophores on Rumen Bacteria (Gram +)

• Extracellular Intracellular

• ATP• H+ H+ • ADP

• H+ H+ • K+ K+

• Na+ Na+

• H+ H+

M

M

Results of Ionophore Use

• Reduces Gram + population:– Proteolytic and amilolytic bacteria

• Decreases proteolysis ----> Greater flow of nonammonia-nonmicrobial 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

At calving CM

23.7011.74**

55.158.3*

3.903.75

Abe et al.(1994)

Prepartum C150 mg/d300 mg/d450 mg/d

14.9113.9113.9014.31

58.658.9

61.0**60.31*

0.460.38**0.400.39*

Wade et al.(1996)

Prepartum CM

15.2412.46*

65.1*62.8

0.4380.581

Stephensonet al. (1994)

Postpartum CM

5.154.34

63.365.5

NANA

Phipps et al.(1997)

Effect of Monensin on Performance of Dairy Cows

Monensin, mg/kd

0 8 16 24

No. cows 215 210 216 217

DMI, kg/d

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

Adapted from Symanowski et al. (1999) and Wagner et al. (1999)a Different from the control (P < 0.05)

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

1.1

Monensin Control Relative risk

Effect of Monensin on Reproductive Performance of CowsBeckett et al. (1998)

FSC Preg. Rate

271/497

444/530

283/486

438/526

0.941.01

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

Control 69.1 16.9 100.1 4.1***

296 ml/d 51.6 33.5** 99.9 1.6

592 ml/d 54.0 26.9** 100.1 2.0

887 ml/d 54.0 25.4** 100.3 2.0

Grummeret al. (1994)

Control1 64.6 19.1 58.9** 3.4

2,347 g/d 57.0 30.3*** 45.3 1.9

Emery et al.(1964)

1 In vitro incubation

Effect of PG Dosage on Blood Metabolites of Feed Restricted Heifers

PG dose (d 12)

0 ml/d 296 ml/d 592 ml/d 887 ml/d Contrast

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)

Effect of Method of PG Delivery on Blood Metabolites of FeedRestricted Cows

PG dosage and delivery

Control 340 O 340 C 340 TMR Contrast

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)

Effect of PG Delivery Method on Rumen Fermentation

PG dosage and delivery

VFA Control 340 O 340 C 340 TMR Contrast

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)

Effect of PG on Performance and Blood Metabolites of Cows

Item

Treatment Milk,kg/d

Insulin,IU/ml

Glucose,mg/dl

BHBA,mg/dl

NEFA,mEq/L

Reference

0 ml/d300 ml/d

24.527.0

NANA

65.466.0

6.734.80

0.4150.384

Fonseca etal. (1998)

0 ml/d500 ml/d

NANA

6.511.1

53.059.2

NANA

0.3860.290

Miyoshi etal. (1995)

0 ml/d1,000 ml/d

33.232.6

0.3540.679***

LowHigh***

LowHigh

0.403**0.234

Studer etal. (1993)

Effect of Propylene Glycol on Liver Lipids and TG

1215182124273033

% (

DM

ba

sis

)

d +1 d +21

Studer et al. (1993)

Control PG 1L/d

2

5

8

11

14

17

% (

DM

bas

is)

d +1 d +21

Studer et al. (1993)

Control PG 1L/d

Effect of PG on Transition Cow Performance

• PG had no impact on milk composition and plasma insulin

• PG increased IGF-I, plasma cholesterol and decreased MUN and NEFA30

31323334353637383940

Kg

/d

Milk 4% FCM

Formigoni et al. (1996)

Control PG 300 g/d

P > 0.15

Effect of Ca Propionate Prepartum on Blood Metabolites of Dairy Cows

Item

Tretment Breed Ca, mg/dl(24hs)

Ca, mg/dl(10 d)

BHBAmg/dl

NEFA,mEq/L

Reference

Control4 tubes

HH

6.877.23

7.958.25

13.110.6

NANA

Goff et al.(1996)

Control6 tubes

HH

7.347.98

8.508.57

13.513.2

0.790.81

Goff et al.(1996)

Control4 tubes

JJ

6.027.23**

8.748.30

6.9*4.4

0.74*0.51

Goff et al.(1996)

Control110 g Ca +454 g PG

HH

4.305.30***

4.904.80

NANA

1.39**0.85

Higgins etal. (1996)

Niacin

Adipose Tissue

TriacylglycerolHSL

DiacylglycerolMonoacylglycerol

NEFA

Blood Compartment

Niacin-

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 Niacineffect

DMI, kg/d 10.2 13.0 10.1 12.6 No

NEL intake,Mcal/d

13.5 21.2 13.5 20.4 No

EB, Mcal/d 0.10 7.39 -0.24 6.76 No

Minor et al. (1998)

Effect of Prepartum Diet on Plasma and Liver Metabolites ofTransition Cows

Diet

LNFC HNFC LNFC + N HNFC + N Niacineffect

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

Hepatic

Glycogen, % 4.5 6.8 4.5** 8.2 No

TG, % 5.0 4.1 7.9* 4.3 No

Minor et al. (1998)

Effect of Niacin During Transition on Performance of Dairy Cows

DMI, kg/d Milk FCM Fat Protein

Prep. Postp. kg/d %

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)

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 HepaticTG, mg %

NEFA,mEq/l

Glucose,mg/dl

Reference

Control 23.0 0.270 61.2

13 g Met 20.0 0.346 59.4

Bertics andGrummer, 1998

Control 12.7 0.820 58.0**

13 g Met 15.4 1.076** 50.3

Bertics andGrummer, 1997

Effect of Methionine or Methionine + Lysine on Metabolism

Item

Treatment Hepatic TG, mg % NEFA,mEq/l

Glucose,mg/dl

16 % CP wk 1 wk 3Control 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

18.5 % CPControl 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

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 Met was detrimental to performance

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

ControlYeast, 57g/d

10.9710.79

1.521.48

-0.08**-0.01

0.190.36

Robinson(1997)

ControlYeast, 15g/d

12.1012.10

1.711.70

-0.060.02

1.091.06

Soder andHolden (1999)

Postpartum

DMI, kg/d DMI, % BW Milk, kg/d Fat, %

ControlYeast, 57g/d

17.3817.62

2.732.78

34.0934.65

4.174.33

Robinson(1997)

ControlYeast, 15g/d

21.9522.90

3.413.54

40.7041.05

4.073.92

Soder andHolden (1999)

Effect of Saccharomyces cerevisiae on transition cow performance (Robinson and Garrett,1999)

• 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

P < .09

P < .28

25.4

27.8

38.6

40.4

18

20

22

24

26

28

30

32

34

36

38

40

42

kg/d

Primiparous Multiparous

Control Yeast Culture

Hypocalcemia (clinical or subclinical)

Milk Production Fertility

Smooth Muscle Function

Rumen and GI Tract Motility Uterine Motility-Immunity

RP Involution

Metritis

DA DMI

Ketosis NEB

Extracellular Ca Pool(8 to 10 g)

Plasma Ca Pool2.5 to 3.0 g

Milk20 - 80 g/d

Fetal Bone2 - 10 g/d

Fecal Loss6 - 10 g/d Urinary Loss

0.25 - 1.0 g/d

PTH and Vit D

Bone ResorptionDiet

Intestine

Vit. D ++

PTH/Vit D ++Calcitonin

Hypercalcemia

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

SO4-2

Cl-

Cell Membrane

H+

-

-

-

-

-

H+

Intracellular andIntravascular

SpacesLumen GI Tract

HCO3-

pH

Strategies for Prevention of Hypocalcemia

DCAD < 250 mEq/kg DCAD > 250 mEq/kg

PTH ReceptorSensitivity

CalcitropicHormones

PassiveAbsorption

Addition of Anions Low Ca diets < 20 g/dVit. D Analogues

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

1.5% Ca

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

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

• 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

Mineral % Diet (DM)

Na 0.1 K < 1.2

S 0.35

Cl 0.5 – 0.7

Ca 1.0 – 1.2

P 0.4

Mg 0.4

Addition of Anions and Urine pH

3

4

5

6

7

8

9

0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7

Anions (Eq)

pH

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