The Nutritionist 2019

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12 Sept20199:00 am EDT6:00 pm EDT

Dr Tom JenkinsClemson University

Nutritional Decisions that Cause Microorganisms in the Rumen to

Drive Down Milk fat!

Nutritional Decisions that Cause

Microorganisms in the Rumen to

Drive Down Milk Fat!

Tom Jenkins

Professor Emeritus

Animal & Veterinary Sciences

Clemson University

Clemson, South Carolina, USA

Nutritional Factors Non-nutritional Factors

genetics

?

stage of lactation

?

season

?

parity

?

breed

disease

Milk fat

Many factors can affect milk fat

Milk Fat

Feed Delivery

TMR Mixing

Feeding Freq

Push up

Low Rumen pHHigh Starch

High Fat

Feed Facilities

Bunk space

Overcrowding

Wild Yeast

Ionophores

Making Milk Fat (C4 to C18)Dr. Tom Jenkins, Clemson University

2 C Acetate

De novo fatty acids (C4 - C16)

BLOOD

Preformed (C16-C18)

C16-C18

Diet & Body

Fat

De novo <C16

Mixed C16

Preformed C18

Takes all three to build milk fat

Data from Woolpert et al. (2017)

% of total FA g/100 g

De novo 24.6 0.97

Mixed 41.2 1.63

Preformed 34.4 1.36

total 100 3.96De Novo 1.8 g/100 g

Preformed 2.2 g/100 g

The Central Role of the Rumen!Dr. Tom Jenkins, Clemson University

De novo milk fat ≤16 C

VFA

Inhibitors

Why the rumen is important for

milk fat?

Acetate

Inhibitors

Step on the gas!

3.6

3.7

3.8

3.9

4

4.1

4.2

0 100 200 300 400 500 600 700 800 900

Milk F

at,

%

Acetate, g/d

J. Nutr. (2017)

Stepping on the brakes!

From J. Dairy Sci. (2008) 91:260.

-55-61

17

-70

-60

-50

-40

-30

-20

-10

0

10

20

30

De Novo Mixed Preform

% Change From CON

De Novo Mixed PreformCON 5% SBO

Milk yield, kg/d 30.3 28.8

Fat, % 3.53 2.73*

Fat yield, kg/d 1.12 0.85*

Where do the inhibitors come from?

Unsaturated FAIN FEED

Saturated FAIN INTESTINES

BIOHYDROGENATION (BH)

What is Biohydrogenation?

Linoleic (18:2) Stearic

18:0

An enzymatic pathway carried on by

ruminal microorganisms.

SUBSTRATE ENDPRODUCT

Linoleic Acid (18:2)Unsaturated

Intermediates

Stearic Acid (18:0)Saturated

BH Has Intermediates

Linoleic Acid

CLA TRANS FA

Stearic Acid

Increases BH Intermediates

Conjugated Linoleic Acid

• CLA inhibits de novo milk fat synthesis

16:0 Palmitic

18:0 Stearic

18:1 Oleic

18:2 Linoleic

18:3 Linolenic

Feed Input Rumen Outflow

From Biochimie (2017) 141:107-120.

t10,c12 CLA dose, g/day

From DeVeth et al. 2004. Lipids

What nutritional signals cause the

t10 shift?

t10 t11

t10 PathwayHigh RUFAL

Rumen Unsaturated Fatty Acid Load (RUFAL)

C18:1(oleic) + C18:2(linoleic) + C18:3(linolenic)

Example RUFAL Values1

Total FA,

% DM

RUFAL,

% DM

lbs DM/100 g

RUFAL

Corn silage 2.4 1.8 12.2

Alfalfa 3.2 2.4 9.2

Corn 4.1 3.4 6.5

Ryegrass 6.2 4.6 4.8

DDG 8.6 6.8 3.2

Cottonseed 16.9 12.2 1.8

Soybeans 17.9 15.1 1.5

Flaxseed 28.5 24.7 0.9

1Random selection of feeds analyzed at Clemson University

T10 Pathway

Feed Delivery

TMR Mixing

Feeding Freq

Push up

Low Rumen pHHigh Starch

High Fat

Feed Facilities

Bunk space

Overcrowding

Wild Yeast

Ionophores

How are these risk factors signaling the

microorganisms to shift to the t10 pathway?

Bacterial Outer Membrane

RUFAL-below antimicrobial

RUFAL-above antimicrobial

Yoon et al. (2018). Int J Mol. Sci.

The interaction among nutritional risk factors that

reduces milk fat is often explained by a shift in the

microbial population community!

• RUFAL antimicrobial effects trigger the population shift.

✓ Antimicrobial effects occur quickly.

✓ Antimicrobial effects target t11 microorganisms.

✓ Antimicrobial effects are enhanced by interactions

among nutritional risks.

Metabolic pathway intermediates in

B. fibrisolvens 20 min after linoleic acid addition.

0

100

200

300

400

500

600

700

800

No Linoleic 0.2 mg/ml linoleic

pm

ol/

mg

pro

tein 95% drop in cell metabolism after just 20 min.

of RUFAL exposure!

J. Appl. Microbiol. (2017)

0

0.05

0.1

0.15

0.2

0.25

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0 1 2 3 4 5 6 7 8 9 10 11 12

t10

, mg

/10

ml

t11

, mg

/10

ml

Hours after am feeding Day 5

t11 t10 Log. (t11) Poly. (t10)Hour Effect (P< 0.01)

t11/t10 Sources

(t11 Pathway)

Butyrvibrio fibrisolvens J. Biol. Chem. (1967, 1971)

Pseudobutyrivibrio Antonie van Leeuwenhoek (2007)

Bifidio Appl Microbiol. Biotech (2010)

Lactobacillus J. Functional Foods (2017)

Roseburia Microbiology (2009)

Sharpea azabuensis Microbiology (2019)

(t10 Pathway)

Megasphaera elsdenii J. Dairy Sci (2010)

Propionibacterium acnes Proc. Natl. Acad. Sci (2006)

Some Lactobacillus spp. Microbiology (2009)

Do fatty acids exhibit ANTIMICROBIAL

properties differently for t11 vs t10?

Modification of Antimicrobial Effects

◼ Low pH enhanced antimicrobial effects of

linoleic on B. fibrisolvens (t11) but not P. acnes

(t10) in recent abstracts by Maia et al. (2018).

◼ Lactate has direct effect

accentuates the antimicrobial effects of unsat FA on

t11 B. fibrisolvens (BMC Microbiol. 2010).

RUFAL – low antimicrobial

RUFAL-high antimicrobial

• Low pH

• High Starch

• Wild Yeast

• Ionophores

• Overcrowding

• etc.

Shut down

microbes using t11

pathway.

Microbes using t10

pathway have more

linoleic acid.

All results suggest that when t11 pathway

is lacking, the t10 pathway must then do

the biohydrogenation of unsaturated fatty

acids.

Frontiers in Microbiol. (2018)

RISK: Overloading the Rumen

with Unsaturated Fatty Acids!

Rumen Unsaturated Fatty Acid Load (RUFAL)

RUFAL = 18:1(oleic) +18:2 (linoleic)+18:3 (linolenic)

Saturated Fatty Acids Don’t Matter

16:0 (palmitic) +18:0 (stearic)

Low Risk RUFAL

hay, unproc corn, unproc cs, whole oilseeds, CaFA

High Risk RUFAL

Proc corn/cs, ground oilseeds, fats/oils, DDG

Distribution of RUFAL

16% of TMR had

RUFAL > 3%.

Lactating Cow TMR

• 15-20% CP

• 28-35% NDF

RISK: Low and variable ruminal pH.

◼ All these can help:

Maintain effective fiber

Don’t let starch kd get too high

Use buffers (Bicarb, K Carb, Na Carb)

Pay attention to feeding management

◼ Mix TMR well

◼ Don’t overcrowd

◼ Push-up

◼ Increase feeding frequency

y = -0.0519x + 0.7994R² = 0.6748

-1.6

-1.4

-1.2

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

10 15 20 25 30 35 40 45

Ch

an

ge i

n m

ilk f

at

%

Starch, % DM

Change in milk fat % caused by added fat vs starch

Feeding Management - Starch

corn oil, sunflower oil, DDG, soybean oil,

linseed oil, fish oil

OTHER RISKS

◼ High yeasts and molds.

Risk increases with yeast counts approaching

1 million cfu/g.

◼ Ionophores

Alone not a problem but intensifies risk when

other proper feeding guidelines not followed.

Get Help From Supplements that

Boost Milk Fat ◼ High palmitic bypass fats

◼ MHA

CAUTION!!

These are NOT a substitute for managing trans-10

risks when milk fat is low!

Thank You!!!

10 October20199:00 am EDT6:00 pm EDT

Dr Michel WattiauxUniversity of Wisconsin-

Madison

Managing Excretions and emissions through Nutrition

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