Embed Size (px)
Citation preview
www.poultryresearchcentre.ca
Current Advances in Broiler Breeder Modeling Research: a North American
Perspective
Martin J. Zuidhof1
R. A. Renema, and A. Pishnamazi
AMEVEABogotá, ColombiaApril 18-19, 2012
1957 broiler 1977 broiler 2005 broiler
Why are Broiler Breeders Difficult to Manage?
The Nutritionist’s Goal• Match nutrient supply to nutrient requirements
The Organism’s Goal• To feel good and be productive
Feel good = f(eat, not eat…)Feel good = f(health, fitness, environment, luxury,
scarcity,…)
‘Properly’ fedUnderfed Overfed
Breeder:Broiler BW ratio* from 1979 to 2005
Renema et al. 2007. WPSJ 63:457-472.*6 wk of age
Uniformity Issue: Competing for a limited resource
Photo courtesy Philippe Dufour, Cobb-VantressBroiler breeder feeding time - Brazil
Uniformity at PhotostimulationReady… Set… GO!
Experimental Design
9
Treatment Diet Form ME (kcal/kg) CP (%) Frequency
Control Standard Mash 2,865 15.0 Daily
Fiber Dilute 25% Oat Hulls Mash 2,200 11.4 DailyScatter Standard Pellet 2,865 15.0 Daily
Skip-a-Day Standard Mash 2,865 15.0 Alternate Days
Sorted Standard Mash 2,865 15.0 Daily
10
Source Probability
Treatment <0.0001Age 0.0049Tmt x Age <0.0001
Sorting
Scatter
Sorting and Scatter Feeding Increased Uniformity
b
c
a
Summary – Uniformity Trial• Sorting was best for uniformity
– Practical consideration: help the smallest group by segregating and giving extra feed
• Scatter feeding and skip-a-day feeding also improved flock uniformity at photostimulation
• Skip-a-day feeding – increased fat stores– reduced breast muscle weight and average egg weight
presumably due to metabolic inefficiencies
11
Feed ManagementComposition / Formulation• Are current recommendations for protein levels too
high?
Current researchComposition restriction: A new paradigm in broiler breeder feeding
Feed ManagementFeed Allocation• Change feed allocations gradually
– Consider the bird’s metabolism(Requirements change gradually)
– How are nutrient requirements changing?• Goal: Match nutrient supply to nutrient requirements
13
Don’t let the bird’s metabolism know that you’ve changed the feed allocation
-- Frank Robinson
Feed Allocation Principles• Use BW gain as an indicator of metabolic status• Weigh frequently• Take the weather into consideration
RECENT RESEARCHManipulating Reproductive Potential: Growth Profile and Photostimulation Age
Experimental Design
• 3 commercial strains• 4 body weight targets• 2 photostimulation ages
– 18 wk– 22 wk
Growth Curve Targets
STANDARD: • Mean target BW profile
Growth Curve Targets
LOW:• 12 wk BW = 75% of STANDARD • Rapid rate of gain to 32 wk
Growth Curve Targets
MODERATE: • 12 wk BW = 150% of
STANDARD • Lower rate of gain to 32 wk
Growth Curve Targets
HIGH: • 12 wk BW = 200% of STANDARD • Minimal rate of gain to 32 wk
Age at First Egg
P-values: Strain=0.29 Feed=0.0047 PS age<0.0001
c bcb
a
Total Egg Production*
*to 58 wk of age
Photostimulation: Early = More Eggs
Photostimulation: Later = More Settable Eggs
So What?
• We may have more flexibility than we sometimes think when manipulating growth curves
When broiler breeders start to lay, they are highly motivated to repartition nutrients away from growth, and toward egg production.
RECENT MODELING RESEARCH
Effect of environmental temperature on maintenance energy requirements of broiler breeders
Core Body Temperature Dynamics
1
Feed Allocation Principles• Use BW gain as an indicator of metabolic status• Weigh frequently• Take the weather into consideration
Pullets: Nutrient Requirement Model
• Account for – Body weight (W)– Temperature (T)– Gain (G)– Age (A)
MEI = A(W0.67) - 0.6107(W0.67)(Te - 21) + 0.9397G
“Maintenance Energy” ModelM
aint
enan
ce E
nerg
y Re
quire
men
t (kc
al/k
g^0.
67)
0
20
40
60
80
100
120
140
160
180
200
Age (d)
0 14 28 42 56 70 84 98 112 126 140
Age related effects (age=x)
MEm = 275.8 - 8.4941x + 0.1778x2 - 0.0016x3 + 5.09E-06x4
Why?
Comparing Results
Partitioning of 55 g of Feed*(2,750 kcal/kg)
*1.3 kg pullet
Gain per 55 g of Feed (2,750 kcal/kg)
*1.3 kg pullet *assuming requirement for gain of 0.928 kcal/g
Hens: Nutrient Requirement Model
• Account for – Body weight (W)– Environmental temperature effect on maintenance (W x T)
• Linear• Quadratic
– Gain (G)– Egg production (E)
MEI = 213.5W0.68 - 5.22W0.68(Te) + 0.11W0.68(Te2) + 0.41G +1.12E
maintenance Egg
Linear nonlinear
Effect of Temperature on maintenance Gain
Nonlinear Effect of T on ME Requirement
Predicted daily ME intake for a 3 kg bird gaining 10 g/d, producing 50 g of egg mass per day, on average
Growth (30 g/d difference)
Growth
Decreasing Post-peak Feed Allocations• Keep birds growing on target• Birds in a positive energy balance will prioritize
nutrients toward egg production
39
Match nutrient supply to nutrient requirements
Feed allocation: nutrient requirements change slowly…Make feed increases as small and as frequent as possible
Use BW GAIN for feed allocation decisions
Principles of Breeder Management
Utilizar la GANANCIA DE PESO de las decisiones de asignacion de alimentacion
Stimulate sexual maturity by changing daylength (not feed)
Support the necessary body weight gain needed with feed
EGGS WILL FOLLOW – they are a hen’s priority
Principles of Breeder Management
Don’t let the bird’s metabolism know that you have changed the
feed allocation
Principles of Breeder Management
Don’t forget……
you are managing something you can’t see!
THE FUTUREPrecision management of individual broiler breeders
Managing Individual Hens
• Providing the right amount of feed to the right bird at the right time BW
Under target
Small meal
Target or higher
Eject from station
Breeder Management Top 101. Know the actual weight of your birds2. Weigh the birds at the same time each day3. Flock uniformity is very, very important4. Avoid high nutrient density diets5. Make sure pullets are at the minimum threshold
BW at lighting6. Don’t make fast increases in feed intake coming into
production
Robinson, 1996
Breeder Management Top 107. Know what you are doing in managing post-peak
feed withdrawal8. Keep an open mind – birds are changing every year
(what worked the last flock may not work this year)9. Don’t put your flock on ‘AUTO-PILOT’10. Stay positive person and keep learning
11. Manage birds according to body weight gain instead of BW
Adapted, Robinson, 1996
How the Benefit Will Be Gained• Stable metabolism• Efficiency• Flock uniformity
– Egg production– Fertility
PRC Sponsors
Project Sponsors
PoultryIndustryCouncilfor Research and Education
