Exploring Gut Development, Function & Nutrition in Pigs
Sheila Jacobi, PhD
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Outline • Growth & Factors Affecting Productivity
• Gut Development • Why it is important
• Factors impacting development
• Postnatal digestive development
• Impact of weaning • Gut health
• Nutritional interventions
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Factors affecting growth/productivity • Genetics/performance capabilities
• Reproduction
• Housing/Environment
• Management
• Mortality/Health
• Nutrition • Feed efficiency → the amount of feed necessary to produce a pound of live weight
gain
Growth “The progressive net accretion of nutrients and their metabolites, which begins at conception and continues as long as nutrient supply exceeds requirements for the oxidative metabolism and regeneration of existing tissues” – Bell et al. 1987 JAS(Supl. 2):186-212.
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The Organ That Controls Nutrient Supply & Why Gut Health is Important The Gut – A Major Metabolic Organ
Gut is 5-7% of body mass but accounts for: • 20-35% of whole body energy expenditure • 20-60% utilization of dietary amino acids
• Gut health is a requirement to ensure feed digestibility,
achieve the optimal intake and realize optimal growth during all phase of pork production
• Optimal digestion and absorption of feed • Absence of gastrointestinal tract illness • ‘Homeostatic’ GI microbiome • Ideal immune status (The gut is largest immune organ) • A state of animal well-being
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GI Tract Transition at Birth
Sangild et al., 2012
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Mother’s Milk Orchestrate GI Development
Bioactive components in mother’s milk
Donovan and Comstock, Ann Nutr Metab 2016;69(suppl 2):42–51
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Factors affecting nutrient “availability” • Digestibility • Absorption of end product of digestion • Metabolism of absorbed products
• Digestibility – probably the most important factor in the
efficiency of feed utilization • Inherent feature of feedstuffs to a large extent
• Absorption and utilization – usually not a major problem but is influenced by the pig (e.g. age, sex, physiological state/health of the gut)
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The post-weaning reality
Weaning-related stressors
Post-weaning starvation
Intestinal integrity Nutrient absorption
Pathogen proliferation Diarrhea
• Dietary changes • Environment • Social interactions
• 45% of weaned pigs no contact with feed in first 15 h • 10% remain with the problem for over 40 h
• Growth depression • Morbidity • Mortality
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Postnatal Digestive Development • Rapid transition in digestive function
• Qualitative and quantitative alterations in digestive enzyme secretion occur
• Dietary intake of substrate influences enzyme expression • Alteration in intestinal architecture
Pluske JASB 2013. 4:1
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Post-weaning Changes in the Small Intestine of pigs Weaned at 21 days
Lalles et al. Anim. Res. 53 (2004) 301–316
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Gut Carbohydrase Development
0
10
20
30
40
50
60
70
1 7 14 30
Enzy
me
Activ
ity
(um
ol/m
in/g
pro
tein
)
Age (d)
Lactase Maltase
Egorova et al. 2001; Ch 13 in Digestive Physiology Of Pigs
Sucrase follows similar development as maltase
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Ontogeny of Lipases
Jensen et al. JAS 1997. 75:437
Pre-weaning Post-weaning
Decrease at weaning
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Ontogeny of Pancreatic Enzymes in the Piglet
Jensen et al. JAS 1997. 75:437
Weaning
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Bacterial Diversity in the GI tract • Approximately 800 species found in the swine gut (Looft et
al 2012). • In humans, bacterial cells are estimated to outnumber the host cells
by a factor of ten, and bacterial genes outnumber host genes by a factor of 100 (Savage 1977).
Frese et al. Microbiome (2015) 3:28
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Why Gut Health is Important
The Gut – A Major Metabolic Organ Gut is 5-7% of body mass but accounts for:
• 20-35% of whole body energy expenditure • 20-60% utilization of dietary amino acids
• Gut health is a requirement to ensure feed digestibility,
achieve the optimal intake and realize optimal growth during all phase of pork production
• Optimal digestion and absorption of feed • Absence of gastrointestinal tract illness • ‘Homeostatic’ GI microbiome • Ideal immune status (The gut is largest immune organ) • A state of animal well-being
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Gut Barrier Function
Groschwitz et al. J Allergy Clin Immunol 2009;124:3-20.
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Factors Impacting Gut Barrier
Moeser and Blikslager, JAVMA, Vol 231, No. 1, July 1, 2007
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Weaning Negatively Impacts GI Health • Weaning presents simultaneous stressors on
young pigs • Nutritional • Environmental • Psychological
• Post-weaning “growth check” is correlated with changes in gut health.
• The goal at weaning is to reduce the negative impact weaning has on production, disease, morbidity and mortality.
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Feed intake is one of main factors affecting gut barrier function
Adapted from Wijtten et al., 2011
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Minimal Feed Intake After Weaning Compromises Gut Barrier Function • Period of temporary starvation after weaning
• Reduce intestinal surface area • Increases intestinal inflammation
4 days post weaning
Moeser et al. Res. Vet Sci 2012. 93:975
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Weaning Compromises Barrier Function
Moeser et al. Res. Vet Sci 2012. 93:975
High TER; intact epithelial barrier Low TER; more permeable epithelial barrier
High Flux Rate; more permeable epithelial barrier Low Flux Rate; intact epithelial barrier
22 Pluske, JASB 2013, 4:1
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Prebiotics* Yeast cell wall derivatives • Oligosaccharide derive from yeast cell wall • Increases pig ADG & ADFI of weanling pigs (Miguel et al., 2004) • Mechanism of action: modification microbiota, anti-adhesive function and inhibition of immune system activation
How does it help with production cost? • Animals remain on feed so they continue to grow • Microbes extract energy from the prebiotic function that can be used in energy maintenance of GI tract in SCFA • Reduces activation of mucosal immune system
*Prebiotics are selectively fermented nondigestible ingredients that allow specific changes in both the luminal microbial population and their activity to promote intestinal health by being fermented to SCFA
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Formula PDX Supplementation Linearly Increases Colon Lactic Acid and Reduces pH
Herfel et al.,2011 J. Nutr. 141: 2139
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.6
5.7
5.8
5.9
6.0
6.1
6.2
6.3
6.4
6.5
6.6
0 1.7 4.3 8.5 17
Col
on la
ctic
aci
d,
umol
/g w
et d
iges
ta
Col
on p
H
Formula PDX, g/L
lactic acid
pH
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Prebiotics Modulate Microbiome (Jacobi et al. unpublished data)
Control
Prebiotic 1 Prebiotic 2 Combined
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Probiotic Summary
Pate
l et a
l. L
ive.
Res
. Int
er.,
2015
. 3(2
):31
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Probiotics Cont.
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Bioactive Amino Acids & Gut Health
Lalles et al. Animal 2009. 3(12):1625
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Role of Nutrients on Gut Health
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Trace minerals
Essential oils
Organic acids Probiotics
Peptides
Bacteriophages
Enzymes Immunoglobulins
31 Trust the gut, beat stressful weaning lags. National Hog Farmer, Feb. 2016
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Questions
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Antibiotics Shifts GI Populations