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Digestibility and absorption of Calcium by growing pigs

Hans H. SteinUniversity of Illinois

http://nutrition.ansci.illinois.edu

Outline

H. H. Stein

IntroductionAbsorption of CaEndogenous CaDigestibility of CaCa requirement

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Caroline Gonzalez-Vega

H. H. Stein

Introduction

• The mineral content in animal body is 2-5%.

• Most abundant minerals in body:– 36-39% Ca (bone ash)– 17-19% P (bone ash)

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Gillespie, 1987; Crenshaw, 2001.

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Ca in body

Ca1% in Extra-and Intra-cellular fluids

99% in bones and teeth

Crenshaw, 2001; Ewing and Charlton, 2007.

Absorption of Ca

Christakos et al., 2014.

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Absorption of Ca

Intrinsic factors• pH (gastric and

intestinal)• Hormones• Vitamin D

Absorption of Ca

Extrinsic factors• Phytate

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Phytate

Phytate

Phytate

Ca

Ca

Ca

Absorption of Ca

Extrinsic factors• Phytate• Microbial phytase

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Phytate

P

IP3

Phytase

P

Phytate

Phytate

Ca

Ca

IP4

P

P

P

Ca

Absorption of Ca

Extrinsic factors• Phytate• Microbial phytase• Fiber• Fat

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Fiber

Increases rate of passageChange pH in GIT

Fat Decreases rate of passageMay form Ca-fat complexes

Fiber and Fat

Ca:P ratioAbsorption and retention of Ca and P are influenced by Ca:P ratio

Crenshaw, 2001; NRC, 2012.

No STTD of Ca

Total Ca: STTD P between 2:1 and 3:1

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Digestibility of Ca

Plant sourcesATTD of Ca: Corn, SBM, canola mealTTTD of Ca: Canola meal

Inorganic sources ATTD of Ca: Calcium carbonate

Animal sources ATTD of Ca: MBM

Requirements of CaBody protein

Total Ca requirements

Body P mass

STTD P requirementsx 2.15

NRC, 2012.

Item 11-25 kg pig

Total Ca, % 0.70

STTD P, % 0.33

STTD Ca, %

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Effect of Ca on ATTD of P

H. H. Stein

Stein et al., 2011

Linear: P < 0.05

Questions on Calcium• Duodenal, ileal, or total tract digestibility?• Endogenous losses of Ca?• Effects of:

– Ca level– Ca source– Phytate– Phytase

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10

Endogenous losses of Ca?

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Gonzalez-Vega et al., 2013

Diets

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ATTD of Ca, %

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Ca level, %

Ca level: P = 0.03; Phytase: P < 0.01; Ca × phytase: P = 0.56

Gonzalez-Vega et al., 2013

Regression

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Dietary Ca intake (g/kg DM)

Apparent total tract digested Ca (g/kg DMI)

Canola meal without phytase

Canola meal with phytase

-0.16-0.19

Total ECaL Gonzalez-Vega et al., 2013

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TTTD of Ca, %

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Ca level, %

Ca level: P = 0.86; Phytase: P < 0.01; Ca × phytase: P = 0.55

70.0

Gonzalez-Vega et al., 2013

H. H. Stein

Duodenal, ileal, or total tract digestibility

Gonzalez-Vega et al., 2013

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Conclusions on Digestibility of Ca• Dietary Ca affects P-Digestibility• Interactions among Ca, P, phytate, and phytase• Diets should be formulated based on STTD of Ca• Requirements need to be expressed as STTD of

Ca• STTD of Ca in feed ingredients need to be

measured

H. H. Stein

Effects of microbial phytase on STTD of Ca in Ca supplements

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Composition of Ca supplements

MCP18.5% Ca21.6% P

DCP21.6% Ca19.2% P

Calcium carbonate41.8% Ca

0.2% P

Composition of ingredients

Corn0.01% Ca

0.58% Phytate

Potato protein isolate0.04% Ca

0.37% Phytate

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85.977.8

60.4

86.378.9

73.1

0

20

40

60

80

100

MCP DCP CaCO3

Without phytase With phytase

STTD of Ca (%) in Ca supplements

a b

Phytase for weanling pigs

60

70

80

90

0 1000 2000 3000 4000

ATTD

of C

a, %

Phytase, FYT/kg

Plateau: 1,155 FYT/kg; 84.7% ATTD of CaAlmeida and Stein, 2013

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Conclusions• Values for STTD of Ca among Ca

supplements were different– MCP had the greatest STTD of Ca

• Microbial phytase increased the STTD of Ca in Calcium Carbonate

• Microbial phytase increased the ATTD of Ca in corn-SBM-CaCO3 diets

Digestible Ca requirements

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Nutrient composition of dietsSTTD P, % 0.36 0.33 0.40

STTD Ca, % 0.32 0.40 0.48 0.56 0.64 0.72 0.72 0.72

Total P, % 0.56 0.53 0.61

Total Ca, % 0.40 0.54 0.67 0.80 0.93 1.06 1.07 1.05

Total Ca:Total P 0.71:1 0.96:1 1.20:1 1.43:1 1.66:1 1.89:1 2.02:1 1.72:1

STTD P, % 0.36 0.33 0.40

Total Ca, % 0.40 0.54 0.67 0.80 0.93 1.06 1.07 1.05

Total Ca:STTD P 1.11:1 1.50:1 1.86:1 2.22:1 2.58:1 2.94:1 3.24:1 2.63:1

Ingredient composition of diets

STTD P, % 0.36 0.33 0.40

STTD Ca, % 0.32 0.40 0.48 0.56 0.64 0.72 0.72 0.72

Corn, SBM, lactose 92.5 92.5 92.5 92.5 92.5 92.5 92.5 92.5

MCP 1.15 1.15 1.15 1.15 1.15 1.15 1.00 1.35

CaCO3 0.05 0.40 0.73 1.05 1.39 1.72 1.80 1.59

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Exp. 1• 256 pigs (Initial BW:11.4 ± 1.2 kg) • 8 diets with 8 replicate pens (4 pigs/pen)• BW (0, 10, and 22 d), ADFI, ADG, G:F

Exp. 1• 1 pig/pen was euthanized • Femurs were collected• Bone ash, bone Ca, and bone P were determined

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Exp. 2• 80 growing pigs (Initial BW:13.1 ± 1.8 kg) • Fecal and urine samples were collected using marker-

to-marker approach

ResultsExp. 1

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STTD Ca requirement, %

0.5

0.53

0.56

0.59

0.62

0.65

0.68

0.2 0.3 0.4 0.5 0.6 0.7 0.8

ADG,

kg/

d

Standardized total tract digestible Ca, %

0.36

STTD Ca requirement, %

0.63

0.66

0.69

0.72

0.75

0.2 0.3 0.4 0.5 0.6 0.7 0.8

G:F

Standardized total tract digestible Ca, %

0.43

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STTD Ca requirement, %

66.5

77.5

88.5

99.510

0.2 0.3 0.4 0.5 0.6 0.7 0.8

Bon

e as

h, g

Standardized total tract digestible Ca, %

0.48

STTD Ca requirement, %

2

2.5

3

3.5

4

0.2 0.3 0.4 0.5 0.6 0.7 0.8

Bon

e C

a, g

Standardized total tract digestible Ca, %

0.48

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STTD Ca requirement, %

1

1.25

1.5

1.75

2

0.2 0.3 0.4 0.5 0.6 0.7 0.8

Bon

e P,

g

Standardized total tract digestible Ca, %

0.56

Growth performance (d0 to d22)

0.59

0.93

0.640.56

0.91

0.630.62

0.97

0.64

0.00

0.25

0.50

0.75

1.00

ADG, kg/d ADFI, kg/d G:F

0.33 0.36 0.40 STTD P, %

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Bone

8.11

3.051.45

9.05

3.45

1.61

10.23

3.82

1.830.00

2.00

4.00

6.00

8.00

10.00

Bone ash, g Bone Ca, g Bone P, g

0.33 0.36 0.40 STTD P, %

Linear P < 0.001

ResultsExp. 2

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Absorbed Ca, g/d

2.282.96

3.794.14

4.95 5.25

0

1

2

3

4

5

6

0.32 0.40 0.48 0.56 0.64 0.72

Linear P < 0.001

STTD Ca, %

Urine Ca output, mg/d

122 204383

731

1124

1534

0

500

1000

1500

0.32 0.40 0.48 0.56 0.64 0.72

Linear P < 0.001Quadratic P < 0.001

STTD Ca, %

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Urine P output, mg/d

548

287

13182 84 88

0

100

200

300

400

500

600

0.32 0.40 0.48 0.56 0.64 0.72

Linear P < 0.001Quadratic P < 0.001

STTD Ca, %

STTD Ca requirement, %

1.5

2

2.5

3

3.5

4

4.5

0.2 0.3 0.4 0.5 0.6 0.7 0.8

Ca

rete

ntio

n, g

/d

Standardized total tract digestible Ca, %

0.52

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STTD Ca requirement, %

1.00

1.50

2.00

2.50

3.00

0.2 0.3 0.4 0.5 0.6 0.7 0.8

P re

tent

ion,

g/d

Standardized total tract digestible Ca, %

0.48

Ca and P in bodyPig Ca:PHigh-lean, 20 kg (g/kg empty BW) 1.38Low-lean, 20 kg (g/kg empty BW) 1.41Barrow, 20 kg (g/kg empty BW) 1.4120 kg (%, FFEBW) 1.54

Ca:P ratio 1.38-1.54

Mahan and Shields, 1998; Wiseman et al., 2009.

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STTD Ca:STTD PPig Break pointBone ash 0.48Bone Ca 0.48Ca retention 0.52P retention 0.48

STTD Ca:STTD P1.331.331.441.33

Ca:P ratio 1.38-1.54

Conclusions• STTD Ca requirements for 11 to 25 kg

pigs:– ADG is between 0.36 and 0.56%, G:F is 0.43%– Bone ash, bone Ca, and bone P is between

0.48 and 0.56%– Ca retention and P retention is between 0.48

and 0.52%

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http://nutrition.ansci.Illinois.edu

H. H. Stein

H. H. Stein

Acknowledgement

http://nutrition.ansci.illinois.edu