Developments in feed evaluation for pigs 80 years Schothorst Feed Research
November 5th, 2014
Outline
Introduction
Energy values and requirements
Amino acid values and requirements
The future?
Outline
Introduction
Energy values and requirements
Amino acid values and requirements
The future?
products
resources
Animal production is constantly facing new challenges
nutrient intake nutient deposition
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
protein lipid carbohydrate fiber ash
Rate, kg DM/d
The transformation of a diet into a pig
GE
nutrient requirements DE
ME
NE
total AA
ileal digestible AA
std. ileal digestible AA
ideal AA profile
Nutritional systems:
a compromise between “value” and “requirement”
nutrient values
The basis for the development of feeding systems (e.g., energy, amino acids, P)
Values and requirements should speak the same language and dialect
Values and requirements are supposed to be additive
The basis for linear least-cost feed formulation
Nutrient values and requirements
Outline
Introduction
Energy values and requirements
Amino acid values and requirements
The future?
Estimation of GE values
GE = 22.6 CP + 38.8 fat + 17.5 starch + 16.7 sugars + 18.6 residue residue = OM – (CP + fat + starch + sugars)
Noblet et al. (1994) J. Anim. Sci. 72:344-354
10 15 20 25 30 35 40 60
70 80 90 100
NDF content, %
Energy digestibility, %
growing pigs: 0.90
Le Goff and Noblet (2001) J. Anim. Sci. 79: 2418-2427
Effect of fiber on digestibility
10 15 20 25 30 35 40 60
70 80 90 100
NDF content, %
Energy digestibility, %
growing pigs: 0.90
sows: 0.64
Le Goff and Noblet (2001) J. Anim. Sci. 79: 2418-2427
Effect of fiber on digestibility
0 10 20 30 40 50 60 70 80 90 100 80
82 84 86 88 90 92 94 96 98 100
Protein content, %
ME:DE, %
Sauvant et al. (2004) Tables of composition and nutritional value of feed materials
The ME:DE ratio depends on how protein is used
deposited protein digestible
protein
excess protein
carbon chain urea
The ME:DE ratio depends on how protein is used
2 NH3 + CO2 + 4 ATP → urea (22.6 kJ/g N)
Lys Met Cys Thr Trp Ile Leu Val Phe Tyr His Arg Ser Gly Ala Glu Gln Pro Asp Asn
0 5 10 15 20 25 30
35 urea carbon chain
Energy value, kJ/g
The ME:DE ratio depends on how protein is used
Energy losses and energy systems
GE Fecal energy
DE Urinary energy, CH4, H2
ME Heat increment
NE Fasting heat production RE
09:00 12:00 15:00 18:00 21:00 00:00 03:00 06:00 09:00 20.25%
20.30%
20.35%
20.40%
20.45%
20.50%
O2 concentration Physical activity
Hour
Oxygen concentration
Meal
Measuring physical activity
Components of heat production
0 5 10 15 20 25 30
Activity Heat increment (short-term) Heat increment (long-term) Fasting
Hour
Energy expenditure, MJ/d
Contribution of tissues to the maintenance energy requirements
van Milgen and Noblet (1999) J. Anim. Sci. 77:2154-2162
MEm = aM (muscle)b + aV (viscera)b
aM = 555 kJ/(kg muscle)0.70/d aV = 1558 kJ/(kg viscera)0.70/d
FHP = aM (muscle)b + aV (viscera)b + aF (fat)b
aM = 457 kJ/(kg muscle)0.81/d aV = 1969 kJ/(kg viscera)0.81/d
aF = -644 kJ/(kg fat)0.81/d
Fasting heat production is affected by the feeding level before fasting
1500 1700 1900 2100 2300 2500 2700 2900
600 650 700 750 800 850 900 950 1000 1050 1100 1150 1200
ME intake, kJ/(kg BW0.60)/d
FHP, kJ/(kg BW)0.60/d
Estimating energy values from digestible nutrients
DE (kJ/g)
ME (kJ/g)
NE (kJ/g)
ME:DE
(%) NE:ME (%)
Protein 23.3 20.4 12.1 88 59
Lipid 38.7 39.3 35.0 101 89
Starch 17.5 17.5 14.3 100 82
Sugars 16.8 16.5 11.9 98 73
Fiber 16.7 15.5 8.6 93 56
Noblet et al. (1994) J. Anim. Sci. 72:344-354
lipid
protein starch sugars fiber
intermediary metabolism
lipid ATP
protein
heat
The transformation of organic matter into a pig
Theoretical efficiency of ATP synthesis
van Milgen (2002) J. Nutr. 132:3195-320
60 70 80 90 100 110 120
kJ ME / ATP
Energy efficiency of glucose ATP
direct 74.2 kJ/ATP = 100%
via glycogen (muscle) 97%
via glycogen (liver) 95%
via glutamate (amino acid) 95%
via glutamate (protein) 82%
via lipid 80%
van Milgen (2002) J. Nutr. 132:3195-320
Outline
Introduction
Energy values and requirements
Amino acid values and requirements
The future?
Law of the minimum (von Liebig, 1850)
Ideal protein (Mitchell et al., 1964)
All essential amino acids are equally limiting for performance:
no deficiency
no excess
Usually expressed relative to Lys:
Lys is typically the first-limiting amino acid in the diet
The Lys requirement (g/kg diet) changes during growth, but the requirements of other amino acids change proportionally to Lys (assumption)
Simple to use: only 1 value for each amino acid to remember (e.g., Thr:Lys = 65%)
Muscle Hair Endogenous secretions Milk
0 5 10 15 20 25 30 35
Val Trp Thr Cys Met Lys
% of protein
Amino acid composition of proteins
0 1 2 3 4 5 6 7 8 9 10 0.0
0.5 1.0 1.5 2.0 2.5 3.0 3.5
Amino acid intake, g/d
Ileal amino acid flow, g/d
Basal
endogenous Indigestible
Specific
endogenous
Endogenous losses increase with increasing amino acid intake
diet ileal indigestible
specific endogenous losses standardized ileal digestible
(SID)
apparent ileal digestible (AID)
basal endogenous losses
Expressing amino acid values and requirements
Basal endogenous losses are:
part of the feed value in an AID system part of the requirement in an SID system
Apparent ileal digestibility (AID):
AID values are not additive
Basal endogenous losses are part of the AID amino acid value (i.e., the value is lower)
Standardized ileal digestibility (SID):
SID values are corrected for basal endogenous losses
SID values are (supposed to be) additive
Basal endogenous losses are part of the SID amino acid requirement (i.e., the requirement is higher)
SID is the preferred mode of expression
Expressing amino acid values and requirements
Factorial calculation of amino acid requirements
products
resources
diet ileal indigestible
specific endogenous losses standardized ileal digestible
minimum oxidation
(=100% - maximum efficiency)
excess deposition
basal endogenous losses maintenance
available
Factorial calculation of amino acid requirements
Item Value
Body weight, kg 50
DM intake, kg/d 2
Protein deposition, g/d 150 Lys content in body protein, % 6.96 Minimum oxidation of Lys, % 28 Maintenance Lys requirement,
mg/(kg BW0.75)/d 28.4
Basal endogenous losses,
mg/kg DM intake 313
0 2 4 6 8 10 12 14 16 18
deposition
minimum oxidation maintenance
basal endogenous losses
SID Lys requirement, g/d
Factorial calculation of amino acid requirements
Body weight gain and protein deposition change in a similar way during growth …
0 20 40 60 80 100 120 140 160
0 100 200 300 400 500 600 700 800 900 1000
0 20 40 60 80 100 120 140 160
Body weight, kg
Body weight gain, g/d Protein deposition, g/d
… but protein deposition and feed intake vary differently
0 20 40 60 80 100 120 140 160
0 500 1000 1500 2000 2500 3000 3500
0 20 40 60 80 100 120 140 160
Body weight, kg
Feed intake, g/d Protein deposition, g/d
Amino acid requirement ~ protein deposition feed intake
The bottom line:
We have to construct these curves!
Model-derived requirements and responses
Conceptually very similar, but different approaches towards:
basal endogenous losses
efficiency of amino acid use
variation among animals
Model-derived Lys requirements for growing pigs
20 40 60 80 100 120 140
0 1 2 3 4 5 6 7 8 9 10
Inraporc NRC
Body weight, kg
SID Lys requirement, g/kg
Model-derived SID Thr:Lys requirements for growing pigs
20 40 60 80 100 120 140
56 58 60 62 64 66 68 70
Inraporc NRC
Body weight, kg
SID Thr:Lys requirement, %
Amino acid InraPorc NRC
Met 30 29
Met + Cys 60 58
Thr 65 (64-65) 64 (61-68)
Trp 18 18
Val 70 66 (65-68)
Ile 55 53
Leu 100 101
Phe 50 61
Phe + Tyr 95 95
His 32 34
Arg 42 46
Average ideal amino acid profile for growing pigs
Outline
Introduction
Energy values and requirements
Amino acid values and requirements
The future?
Ruminants
Monogastrics Common
units
Milk
Meat
Pigs
Poultry
Broilers Layers Growing pigs
Sows
1875
1850 1975 2000
Segmentation of feed unit systems
(Daniel Sauvant, EAAP workshop, Uppsala, June 4th 2005)
Is the cow a pig with a rumen?
Is the pig a chicken without feathers?
Countries have developed “home-made” nutritional systems, which come in different flavors
Budget and brains become limiting to account for new challenges in current systems
Past initiatives to harmonize feeding systems have failed:
a “my-system-is-better-than-yours” attitude
personal initiatives without institutional backing or funding
willingness but no commitment
International cooperation in feed evaluation
EAAP workshop “Harmonization of Feed Evaluation Systems”
(Uppsala, 2005)
INRA-WUR meeting (Paris, 2005)
EAAP workshop “The future of feeding systems and feed evaluation in Europe” (Bratislava, 2012):
COST action proposal “Towards a unified European system of farm animal nutrition” (March 2013)
COST action proposal “Multifunctional feeding systems for sustainable animal production - a framework for research and knowledge transfer” (September 2013)
EAAP workshop programmed (Warsaw, 2015)
International cooperation in feed evaluation
Methods of evaluation: rapid, cheap, “no animal”, precise
Technological aspects and feed additives
A more mechanistic approach towards digestion and absorption (nutrient-nutrient and animal-nutrient interactions)
Metabolic efficiency
Account for “non-productive” aspects, multi-facetted responses (e.g., animal health and welfare, product quality, environment)
“New” animals, new feeds
Account for variation (feeds, animals)
Across-species approach
From a system of requirements to a system of responses
From models to tools
Challenges for future feeding systems
(EAAP workshop, Bratislava, August 31th, 2012)
1850 1980
real-time monitoring
precision livestock farming?
2010
nutrition as “art”
modeling &
computing characterization
nutrient discoveries
1950
The future?
The future?
observe understand
predict control
products
resources
The past, the present, and the future
Acknowledgements:
Roberto BAREA Ludovic BROSSARD
Alberto CONDE Jean-Yves DOURMAD
Serge DUBOIS Mathieu GLOAGUEN Etienne LABUSSIÈRE Laurent LE BELLEGO Nathalie LE FLOC’H
Gwénola LE GOFF Jean NOBLET Bernard SÈVE
Staff at the UMR Pegase research unit
