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Managing for gut health

Dr. Greg PennerAssociate Professor and Centennial Enhancement Chair in Ruminant Nutritional PhysiologyUniversity of Saskatchewan

www.usask.ca

Take-home messages A consistent supply of DM and nutrients are

required to maintain gut health Production responses have not been well

characterized but can be extrapolated Management strategies to minimize variation in

intake may yield greatest rewards Recovery following a challenge takes time, but

can be accelerated

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Requirements of the gastrointestinal tract Absorptive and secretory

• Supply energy • Regulates ruminal pH• Urea recycling

Barrier• First arm of the immune response• Prevents pathogen and antigen translocation

Communicative• Facilitates cross-talk between host and microbiota• Nutrient sensing

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Why is there variation in rumen pH?

5.0

5.4

5.8

6.2

6.6

7.0-2

880

-252

0

-216

0

-180

0

-144

0

-108

0

-720

-360 0

Rum

inal

pH

Time relative to the challenge, min

ControlResistantSusceptible

Penner et al., 2009

020406080

100120140160180

Control Resistant Susceptible

Dur

atio

n pH

< 5

.8, h

/180

min

c

a

b

P < 0.05

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Greater absorption reduces risk for low pH

0

2

4

6

8

10

12

14

16

Acetate Butyrate

Upt

ake,

nm

ol/(m

g pr

otei

n ×

min

)

Control

Resistant

Susceptible

bb

bba

a

Penner et al., 2009

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Barrier function Ability to promote selective permeability

• Allow absorption of nutrients• Prevent movement of non-desired compounds,

toxins, enteric flora

Damage occurs in two forms• Lesions• Compromised tight-cell junctions

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Barrier function

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Weimer et al., 2010; JDS

Evidence supporting stability in the rumen microbial community structure

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Gut health is more than just the rumen

012345

Rumen Omas. Abomas. SI

Wei

ght,

kg

Gorka et al., 2017

Region Length, mDuodenum 0.53Jejunum 21.62Ileum 0.80Cecum 0.22Colon 4.63

Total 27.80Length in ft 91.2 Watanabe et al., unpublished

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Rumen acidosis: more than just the rumen!

0

1

2

3

4

5

6

7

8

9

Rumen Duodenum Jejunum Ileum Cecum Proximalcolon

Distalcolon

pH

Control Acidosis

* * * *

Pederzolli, unpublished

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What is gut health?

Good types of microbes

Large rumen papillae

Good fibre digestion capabilityOptimal bacterial protein production

Efficient nutrient absorption

Adequate capacity

Balanced residence time and passage rate

Good barrier function

Regulated pH

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What is gut health?

Forage-basedAttributes Active and regulated microbial

community (fibre digestion) Nutrient absorption Barrier function

Requirements Consistent supply of dry matter and

nutrients

Concentrate-basedAttributes Active and regulated microbial

community (starch digestion) Nutrient absorption Barrier function

Requirements Consistent supply of dry matter and

nutrients

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Challenges to gastrointestinal function?

Inherent challenges within current production settings• Management

• Weaning• Dietary challenges

• Environment • Heat stress• Competition

• Physiological • Parturition

Low/transient low feed intake

Rapid dietary change / induction of rumen acidosis

www.usask.ca5.5

5.6

5.7

5.8

5.9

6.0

6.1

6.2

6.3

6.4

6.5

0 2 4 6 8 1012141618202224

Incu

bato

r pH

Control Low pHAlternating Diurnal

0

10

20

30

40

50

60

ND

F di

gest

ibili

ty, %

DM

Direct effects of ruminal acidosis

Calsamiglia et al., 2002; JDSC

ontr

ol

Low

pH

Alte

rnat

ing

Diu

rnal

a

b

aa

P < 0.05

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050

100150200250300350400

Dur

atio

n pH

< 5

.6, m

in/d

0

5000

10000

15000

20000

25000

LPS,

EU

/mL

Low pH induces an inflammatory response

Khafipour et al., 2012: CJAS

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0

5

10

15

20

25

30

35

LBP,

ug/

mL

0

5

10

15

20

25

30

35

SAA

, ug/

mL

Low pH induces an inflammatory response

Khafipour et al., 2012: CJAS

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Barrier function of the rumen epithelium

Aschenbach and Gäbel, 2000; JAS

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Acidification impairs absorption

Wilson et al., 2012; JAS

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750 μm 600 μm

Steele et al., 2009

CONTROL ACIDOSIS

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2K

100 µm150 μm 100 μm

Steele et al, 2009

CONTROL ACIDOSIS

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Inconsistent nutrient supply: the real challenge for gut health

Variation in DMI and nutrient intake alters:• Nutrient supply for microbes• Growth response and antigen release• Nutrients available for cattle• Function of the rumen and whole gut

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Weaning compromises total tract barrier function

• 14 newborn Holstein bull calves

• Weaned on d 42 after a 7 d step-down program vs. or not weaned

• Cr-EDTA used as an indicator of barrier function

Greater urinary Cr = reduced barrier function

Wood et al., 2015: JDS

Not weaned

Weaned

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Low feed intake for newly received feedlot cattle

Week relative to arrivalVariable 1st week 2nd week 3rd and 4th weeksDMI (% of BW) 0.5% to 1.5% 1.5% to 2.5% 2.5% to 3.5%

Hutcheson and Cole, 1986; JAS

0

10

20

30

40

50

60

Acetate Propionate Butyrate

Abs

orpt

ion,

%

of p

re-fe

ed

with

draw

al

Gäbel et al., 1993

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Variation in nutrient supply: beef cow example Swathgrazing – forage allocation cycle

• 3 d/paddock or longer

-100

0

100

200

300

400

500

Corn grazing Barley swathgrazing

Greenfeed inDrylot

Dur

atio

n pH

< 5

.8,

min

/d Day 1Day 2Day 3

Jose, Penner, McKinnon, Lardner, unpublished

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Information Required Does the severity of short-term feed restriction

affect the absorptive and barrier functions of the gastrointestinal tract?

Does the severity of short-term feed restriction affect recovery of absorptive and barrier function?

Can we manipulate the diet to mitigate the response?

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18 cannulated Angus heifers• 3 treatments

• 75% of feed ad libitum• 50% of feed ad libitum• 25% of feed ad libitum

5 periods

Baseline Feed restriction Recovery 1 Recovery 2 Recovery 3

Zhang et al., 2013; JAS

Ingredient , % of DMBarley silage 30Grass-Alfalfa hay 30Barley grain (rolled) 32Pellet 8

Nutrient composition DM,% 65.8 ± 1.9OM,% of DM 92.3 ± 1.2CP,% of DM 11.2 ± 0.4Fat, % of DM 1.8 ± 0.0NDF,% of DM 40.1 ± 0.4

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Feed restriction decreases the VFA (nutrients for cows) in the rumen

Zhang et al., 2013

a

b

a

c

a

d

0102030405060708090

100

BASE FR

Tota

l rum

inal

SC

FA, m

M

Experimental period

P < 0.001

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Rumen pH increases during feed restrictionTreatment × period; P < 0.001

0

20

40

60

80

100

120

140

160

BASE FR

Dur

atio

n (p

H <

5.5

), m

in/d

Experimental period

Period; P < 0.001

Zhang et al., 2013

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Nutrient absorption is reduced with feed restriction

0

100

200

300

400

500

600

700

BASE FR

Tota

l SC

FA, m

mol

/h

Experimental period

Treatment; P = 0.080Period; P = 0.091

0

100

200

300

400

500

600

700

75% 50% 25%

Tota

l SCF

A, m

mol

/h

Treatment

Zhang et al., 2013

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Barrier function of the gut is reduced with feed restriction Treatment × period; P < 0.001

Zhang et al., 2013

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Feed restriction impacts cattle when they return to full feed conditions

Treatment × period; P < 0.001

Zhang et al., 2013

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Ad libitum feeding after feed restriction induces rumen acidosis

0

50

100

150

200

250

300

FR REC1 REC2 REC3

Dur

atio

n (p

H <

5.5

), m

in/d

Experimental period

Quadratic; P < 0.001Treatment × period; P < 0.001

Zhang et al., 2013; JAS

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Absorption capability did not recover until about 3 wk after feed restriction

Treatment × Period; P = 0.009

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Management strategies to improve gut health Consistent feed supply that meets nutrient

requirements• Good husbandry, bunk management, grain processing

Feed additives that help to stabilize rumen fermentation

• Ionophores, yeast, probiotics, essential oils, etc. Can we predict the low feed intake event?

• Recovery diets?

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Can We Mitigate the Response by Changing the Forage-to-Concentrate Ratio? Animals and Experimental Design 20 cannulated Angus heifers

• 4 treatments• High forage/High forage• High forage/Moderate forage• Moderate forage/High forage• Moderate forage/Moderate forage

Baseline Feed restriction Recovery 1 Recovery 2 Recovery 3

Albornoz et al., 2013

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Role of forage in recovery after low feed intake

Albornoz et al., 2013; JAS

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Low feed intake decreases SCFA absorption

0100200300400500600700800

Baseline Restriction

SCFA

abs

orpt

ion,

mm

ol/h

P = 0.038

Albornoz et al., 2013; JAS

0

2

4

6

8

10

12

14

Baseline Restriction

DM

I, kg

/d

High forageModerate forage

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0

2

4

6

8

10

12

Week 1 Week 2 Week 3

DM

I, kg

/d

0

50

100

150

200

250

300

350

Week 1 Week 2 Week 3

Dur

atio

n pH

< 5

.5, m

in/d

Feeding a high forage diet improves recovery

ab

cbc

abaab

b

a

b

b

ab

ab

Treat x period, P = 0.033 Treat x period, P < 0.001

Albornoz et al., 2013; JAS

High forage

Moderate forage

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Nutritional strategies to accelerate recovery of the gastrointestinal tract (GIT) Several nutrients may help promote GIT function

• Butyrate Gorka et al., 2013; Kawalski et al., 2015

• Betaine• Coccidia infection Kettunen et al. 2001; Fetterer et al. 2003

• Antioxidants• Superoxide dismutase benefits GIT in mice Vouldoukis et al. 2004

• May counteract hypoxic conditions Dengler et al., 2015

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Use of a compound feed additive to accelerate recovery of the GIT n = 32

Fed ‘High’ 3 d low feed

intake at 50%

TreatmentIngredient, % DM High Storm Storm+Barley silage 9 20 20Barley grain 79 67.5 66.6Min/vit 12.5 12.5 12.5RP betaine 0.7Antioxidant 0.01Butyrate 0.2

Penner et al., unpublished

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Use of a compound feed additive to accelerate recovery of the GIT

Treatment

Ingredient, % DM High Storm Storm+

Barley silage 9 20 20

Barley grain 79 67.5 66.6

Min/vit 12.5 12.5 12.5

RP betaine 0.7

Antioxidant 0.01

0.2

Baseline LFI

CON = no LFI

Recovery

Penner et al., unpublished

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Increasing the F:C ratio and use of a compound supplement stabilized DMI

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Baseline Challenge Recovery

Dry

mat

ter i

ntak

e, k

g/d

CON LFI STORM STORM+Treatment x period, P < 0.001

Only STORM+ recovered to baseline DMI after low feed intake

Penner et al., unpublished

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Increasing the F:C ratio and use of a compound supplement stabilized pH

4.0

4.5

5.0

5.5

6.0

6.5

7.0

Baseline Challenge Recovery

Mea

n ru

min

alpH

CON LFI STORM STORM+Treatment x period, P = 0.022

Penner et al., unpublished

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Increasing the F:C ratio and use of a compound supplement improved absorption

0

200

400

600

800

1,000

Acetate Butyrate

Flux

rate

, µm

ol/(c

m2

×h)

CON LFI STORM STORM+

P = 0.089

P = 0.011a

b

ab

b

Penner et al., unpublished

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Take-home messages A consistent supply of DM and nutrients are

required to maintain gut health Production responses have not been well

characterized but can be extrapolated Management strategies to minimize variation in

intake may yield greatest rewards Recovery following a challenge takes time but

can be accelerated

www.usask.ca

Thank you