Animal, Gut, MicrobiomeNutrition in the 21st Century Knud Erik Bach Knudsen Aarhus University Department of Animal Science
Ponencia patrocinada por:
Knud Erik Bach Knudsen Aarhus University Department of Animal Science Director del Departamento de Nutrición molecular y reproducción. En los últimos 25 años sus estudios se han basado en carbohidratos y fitoquímicos bioactivos. Sus trabajos más recientes han sido en la interfaz de nutrición humana que enfatiza el uso de modelos animales para comprender el modo de acción de los carbohidratos y fitoquímicos. Actualmente es el principal supervisor de varios proyectosClic de doctorado. Tiene 164 para editar publicaciones referenciadas en revistas, y 90 libros y memorias, título de la presentación entre otros.
Points to be addressed
Introduction Digestion and absorption in stomach and the small
intestine Fermentation processes – the microbial community Fermentation processes – microbial end-products Special conditions with newly weaned piglets The challenge for the 21st Century Take home message
Introduction – the challenge The world´s population is expected to increase to 9.2 billion by 2050 Due to the global change in diet preferences and lifestyle, the worldwide demand for animal derived food products is expected to increase with a growth rate that is higher than the estimated growth of the world population This calls for considerable more efficient food production systems Paradigm shi+ required in animal produc4on. By the year 2050 animal produc4on systems produce “two 4mes more with two 4mes less”.
Introduction, cont..  Improved food production systems can be obtained by improved feeds, increased feed efficiencies, reduced ecological footprint, and increased animal health and welfare.  Improvement in feed efficiency must go hand-inhand with a reduction in the use of e.g. in-feed antibiotics which have been heavily used in the past to increase efficiency but which in the long run can cause antibiotic resistance
Digestion and absorption in stomach and small intestine
The diges2on of carbohydrates in pigs Microflora
α-‐amylase
Variety of microbial fibre
SCFA LA Gases
degrading enzymes
No endog enouiso-‐ s fibre Sucrase, degrading enzy&m es maltase glucoamylases
Glucose Fructose
Galactose
The small intestine is the main site for nutrient digestion and absorption Percentage Small intes4ne
Large intes4ne
66
34
Protein (N*6.25)1
89
11
Fat
99
1
Carbohydrates2
89
11
Inorganic materials Organic materials
1 Apparent values
2 The the rela4ve distribu4on of diges4on in the small and large intes4ne will be
influenced by the dietary fibre level.
Fermentation processes – the microbial community
Bacteria in the gastrointestinal tract of pigs Bacteria (cells per g digesta) pH Stomach 108-9 pH 2-5
Proximal SI 108 pH ~6
108-‐9
Caecum 1010 pH 5.5-6.5
Distal SI 109 pH 6-7
Colon 1011 pH 6-6.5
1011
Diges2on and fermenta2on processes -‐ compe22on
blood
Sugars Starch Protein
monosaccharides amino acids
Fiber Protein
Digestion and fermentation Compete with the host for easily digestible nutrients
blood
Fermentation acetate propionate butyrate
and anaerobic respiration Contribute with energy to the host (SCFA)
Dietary fibre fermentation – the microflora • Firmicutes and Bacterioidetes are the two dominating phyla • Bacteria belonging to: • Streptococcus spp. • Lactobacillus spp. • Eubacterium spp. • Fusobacterium spp. • Bacteriodes spp. • Peptostreptococuss spp. • Bifidobacterium spp. • etc.
Kim and Isaacson (2015)
Development in microbial phyla by age ~80% ~55% ~30% ~10%
(Diet: Corn and soybean meal)
Kim et al., 2011
Profiles of gut microbes in GI tracts and feces at the rank of phylum
Zhao et al (2015).
Fermentation processes – microbial end-products
Fibres are the main nutrient for the fermenta2on in the large intes2ne 900
Flow/of/organic/ma8er/(g/d)
800
J
700
J
J J J JJ J J JJ J J J J J J J JJ J J JJ J J J JJJ J J JJ J J J JJJJ JJ JJ J J JJ J J J JJ J J J J J J J JJ J J
600 500
Barley/SBM diet
400 300 200
Wheat/SBM diet
100 0
J J J
J
0
100
200 300 400 Intake/of/fibre/(g/d)
500
The cons4tuents most significantly influenced by fibre: • NSP • Protein (nitrogen) Minor effects on: • Starch • Fat
600
Bach Knudsen et al. (2013).
1) Epithelial and inner mucin layer 2) Diffuse mucin layer 3) Gut lumen-‐liquid phase (diverse microbial community) 4) Gut lumen-‐substrate par4cles (specialist primary colonizers)
Flint, H. J. et al. (2012).
Microbial microenvironments within the large intes2ne
Fermenta2on processes – microbial compe22on › The metabolic output from the microbiota is regulated through several mechanisms: › Within individual species where the same substrate can give rise to different products due to fermenta4on via different metabolic routes › The same substrate can be processed via different routes depending on the rate of supply or the physiology and the environment of the bacteria cell › Cross u4lisa4on – acetate to butyrate as influenced by pH
Concentration of microbial endproducts Concentra2on, mmol/L Substrate
LA
SCFA
3-‐18
2-‐9
21-‐25
22-‐25
Stomach
Sugars, OS
Cranial 2/3 of small intes4ne
OS, starch deg. products, sNSP
Last 1/3 of small intes4ne
OS, starch deg. Products, sNSP
Caecum and proximal colon
sNSP, iNSP
3-‐6
85-‐116
Middle and distal colon
iNSP
<1
56-‐95
OS, oligosaccharides; sNSP, soluble non-‐starch polysaccharides; iNSP, insoluble non-‐starch polysaccharides.
Special conditions with newly weaned piglets
The challenging weaning process Sows diet (liquid milk)
Separa4on from the mother Moving and mixing Change in environmental temperature
Plant based diet (solid complex) Change in structure and func4on of the gut Frequently outbreaks of diarrhoea Low level of feed intake Ac4ons in the past: In-‐ feed an2bio2cs
Challenges for the future: Op2misa2on of the gut environment by dietary means
Acute and adap2ve phases in development of early-‐weaned pigs
Burrin & Stoll (2003)
Morphologically adaptation of the gut in the immediate p.w. period Unweaned
Weaning diet
Unweaned
Weaning diet
Milk at high level
Milk at low level
Milk at high level
Milk at low level
600
140 abc fg
hi
ade
400 fh ce bd
300
d
130
gi
Crypt depth, µm
Villous height, µm
500
c ab
120
cd
110
200
a
b
100 0
4 Days after weaning
7
0
Feed intake of greater importance than the dietary composition
4 Days after weaning
7
Beers-‐Schreurs et al (1998)
Digestion carbohydrates (% of intake) in the small intestine as influenced by age N
Starch
NSP
Piglets, 0-‐10 days post-‐weaning
9
73
3
Piglets, 14-‐28 days post weaning
8
95
14
Growing pigs
78
96
21
Sows
3
93
30
NSP, non-‐starch polysaccharides.
Piglets are more sensi2ve to fibre than older pigs
The challenge for the 21st Century • Piglets • Growing-‐finishing pigs
Different elements in the gut ecosystem Diet
Macronutrients Indigestible components Micronutrients Additives ANF
Gut mucosa Mucus layer Epithelium GALT
Microflora Commensal bacteria Transient bacteria (pathogens) Conway (1994) and Montagne et al. (2003).
The capacity to digest in the small intes2ne influences amount and composi2on of substrate for the large intes2ne NSP, g/kg DM 7
80
120
52
46
42
2
24
36
54
70
78
15
13
12
4
43
65
19
56
77
Intake: 300 g/d Recovery (g), 0-14 d p.w. Starch NSP T-CHO Intake 600 g/d Recovery (g), >14 d p.w. Starch NSP T-CHO
Digestibility of starch in non-heated feeds 9-28 days post weaning
Heat treated
Lærke et al. (2003); Hopwood et al. (2004); Pluske et al. (2007); Jensen et al. (1998); Gdala et al. (1997).
How can we feed the animals so that we stimulate a desirable microbiota? Ø By the use of prebio4cs • Def. of a prebio4c: Non-‐diges4ble food ingredients which beneficially affects the host by selec4vely s4mula4ng the growth and/or ac4vity of one or a limited number of health-‐ promo2ng bacteria in the intes4nal tract thus improving the host’s intes4nal physiology (FAO, 2007).
Influence of dietary carbohydrate on phyla composition › Inulin with variable chain length influence the abundance of phytolytes belonging to Lactobacillus spp. and Bifidobacterium spp. › BD, background diet; HP, long chained inulin (DP 10-‐60); P95, short-‐chained (DP 2-‐7); Synergy = HP:P95 (1:1);
Resistant starch type 3 influence the Firmicutes to Bacteroides ra4o
Paqerson et al (2010).
Haenen et al (2013).
How can we feed the animals so that we stimulate a desirable microbiota? Ø By the use of prebio4cs • Def. of a prebio4c: Non-‐diges4ble food ingredients which beneficially affects the host by selec4vely s4mula4ng the growth and/or ac4vity of one or a limited number of health-‐ promo2ng bacteria in the intes4nal tract thus improving the host’s intes4nal physiology (FAO, 2007).
Ø By in situ produc4on of prebio4cs alone or in combina4on with probio4cs
Exogenous enzymes influence the composition of the substrate for the microbiota B
Viscosity
AXOS High molecular weight AX
Rye
Wheat-‐fine
Wheat-‐coarse
Lærke et al (2015)
Arabinoxylan is not prebiotic whereas arabinoxylan oligosaccharides and xylooligosaccharides are
Broekaert et al. (2012)
Cour4n et al. (2008).
How can we feed the animals so that we stimulate a desirable microbiota?
Ø By the use of prebiotics • Def. of a prebio4c: Non-‐diges4ble food ingredients which beneficially affects the host by selec4vely s4mula4ng the growth and/or ac4vity of one or a limited number of health-‐ promo2ng bacteria in the intes4nal tract thus improving the host’s intes4nal physiology (FAO, 2007). Ø By in situ production of prebiotics alone or in combination with probiotics (synbiotics)
Prebio4cs will provide the nutrients
Probio4cs with health promo4ng proper4es
Synergistic effect of protease and direct-fed microbial (DFM) on digestible energy in grower pigs
PAYLING ET AL (2017)
Zinc oxide in the immediate postweaning period Zinc oxide (ZnO) at high doses (2000-4000 mg/kg) has been widely used in the feeds in the postweaning period because of its diarrhoea preventing effect and positive effect on performance Recently, however, concern has been raised about such high doses due to the environmental impact and the risk of developing microbial resistance These undesired effects of ZnO has stimulated to the development of new types of ZnO – porous and nano ZnO
Faecal zinc oxide concentrations and copy number of the Escherichia group in weaning pigs fed different amounts and preparations of ZnO
Vahjen et al. (2016)
Effect of zinc oxide sources on faecal enterobacteria
300 mg/kg HiZox® was as efficient as 3000 mg/kg of the standard ZnO At 150 mg/kg, HiZox® induced a stronger response than conven4onal ZnO Vahjen et al. (2016)
How can we feed the animals so that we stimulate a desirable microbiota?
Ø By the use of prebio4cs • Def. of a prebio4c: Non-‐diges4ble food ingredients which beneficially affects the host by selec4vely s4mula4ng the growth and/or ac4vity of one or a limited number of health-‐promo2ng bacteria in the intes4nal tract thus improving the host’s intes4nal physiology (FAO, 2007). Ø By in situ produc4on of prebio4cs alone or in combina4on with probio4cs (synbio4cs) Ø By the avoidance of microbial disturbing factors
Antibiotic treatment has a profound influence on the microbiota and fecal composition
An4bio4c treatment affected 87% of all metabolites detected many of which has a physiological role to play.
Antunes et al. (2011).
Take home message Efficient degradation and absorption of nutrients from the gut and the maintenance of a diverse and balanced microflora are key elements for high feed efficiency and animal health The commensal microbiota is pivotal not only for degradation of indigestible complex carbohydrates but also for competitive exclusion of pathogens, production of antimicrobials, etc The challenge for the 21st century is to use knowledge on dietary feed ingredients and additives to formulate diets that optimize growth, feed conversion and health without the use of agents that can lead to antibiotic resistant Options available: By heat processing of the feed for improved starch (nutrient) digestibility By use of prebiotics By in situ production of oligosaccharides By in situ production of oligosaccharides in combination with probiotics (direct fed microbial) By new types of ZnO provided at physiological levels By improving of our knowledge on the impact of small organic molecules in nutrition and health By other means (organic and inorganic acids, yeast, etc…)
AARHUS UNIVERSITET
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