Pas Reform Academy has dedicated more than 30 years to studying the needs of the growing embryo: to understanding the effects of genetic advancement on the performance of our commercial poultry breeds. Extensive scientific knowledge combines with decades of practical, hands-on hatchery experience – to meet new and emerging challenges in the modern hatchery.

1. Pas Reform
Academy
Putting science into practice
2nd Edition | Including 21 day embryo development poster
Pas Reform
Hatchery Technologies

2. Contents
1 Optimizing poultry production from egg to chicken 33 Red hocks in day old chicks or poults
2 Data analysis: a critical path to improved hatchability 34 Empty shells. A valuable source of information
3 Hatching egg quality 35 Spray vaccination of day-old-chicks at the hatchery
4 Uniform eggs are laid by uniform hens 36 Maintaining the ideal climate for chick handling and
transport
5 Establishing true fertility in hatching eggs
37 Improving transport performance
6 Managing fertility: good breeding shows
38 Brooding chicks; a matter of care
7 Care of the egg: from nest to farm store
39 Preventing Omphalitis to reduce first week mortality
8 Hatching egg transport
40 Dealing with exploders
9 Impact of hairline-cracked eggs on hatchability and chick
performance 41 Role of cleaning and disinfection
10 Pre-storage incubation: a matter of routine? 42 How effective is your cleaning programme
11 Storage of hatching eggs 43 Keeping the hatchery free of Aspergillus
12 The importance of preventing ‘sweating’ eggs 44 Effective rodent control on breeder farm and hatchery
13 Formalin-free hatching egg disinfection: an achievable 45 Selecting a hatchery location
goal!
46 Optimising hatchery design for peak performance
14 The effects of setting eggs small end up on hatchability
47 Modernizing or expanding a hatchery
and chick performance
48 Building materials
15 The benefits of single-stage incubation to food safety
49 Hatchery flooring and drainage
16 How hatchery management changes when starting ­
single-stage incubation 50 Ergonomic benefits in the hatchery
17 Pre-heating: an effective tool for chick uniformity 51 Weighing the benefits of automation in the hatchery
18 Finding optimum incubation temperature 52 The relevance of Hatchery Climate Control
19 Managing incubation temperature to combat increased
early mortality
Hatchery Manage­ ent Training
m
20 Optimal weight loss profiling during incubation
21 Adjusting ventilation
22 Incubation at high altitudes
23 Relevance of turning
24 Circadian Incubation
25 To candle or not to candle, that’s the question…
26 When and how to transfer eggs to the hatcher
27 Hatcher basket hygiene for a clean start
28 Creating the ideal hatching climate
29 Managing the hatch window
30 Incubation times in the modern hatchery
31 Optimum timing for pulling day old chicks
32 Reconciling maternal (flock) age and chick quality
Originally published in International Hatchery Practice

3. Introduction For more than 30 years, Pas Reform has
studied the needs of the growing embryo,
to understand the impact of genetic
advancement on the performance of
modern poultry breeds in incubation.
The forefront of scientific understanding
combines with more than 90 years of
hands-on hatchery experience, to meet
new and emerging challenges in the
modern hatchery.
This 2nd Edition of articles published by
Pas Reform Academy, answers 52 of the
questions more frequently asked by
hatchery managers worldwide – in a
single volume for easy reference.
Covering a diversity of hatchery-­
management related topics, from data
analysis to fertility; optimizing weight
loss to preventing omphalitis, each article
in­ orporates the latest data, to give
c
hatchery managers easy reference to the
latest insights for best practice and
o
­ ptimized performance.
If you cannot find what you are looking for,
or would like more detailed information on
any hatchery-related topic, please contact
us. We will be pleased to help.

4. 1 Step in incubation
Egg handling at the
farm and during
Quantifiable criteria:
–– emperature and relative humidity at the farm and during transport;
t
egg temperature on arrival (use portable dataloggers)
Optimizing poultry transport ––flock specific data: strain and age, lay%, health status
–– ercentage of first class hatching eggs
p
production from egg –– ercentages of dirty eggs, floor eggs, cracked eggs and eggs with hairline
p
cracks, upside down eggs
to chicken
Egg storage ––temperature and relative humidity
Preparation for ––flocks age and length of storage
i
­ ncubation: egg traying, ––average egg weights and coefficient of variation (CV)
prewarming, preheating –– emperature and duration of preheating in the setter (or of prewarming
t
Hatching egg quality and incubation in the setter room)
conditions influence broiler performance.
It is therefore important to continually Incubation in the setter ––start of incubation and time to reach the temperature set points
optimize every stage of incubation ––incubation program (temperature, relative humidity, ventilation profiles)
management, based on specific protocols ––egg weight loss
for quality control and best performance.
Transfer to hatchers ––incubation time at moment of transfer
In addition to data collection and data ––percentage of clear eggs
analysis, open, regular communication ––results of break-out of clear eggs
between breeder farm, hatchery and
broiler farm is essential, both for quality Incubation in the ––hatcher climate (temperature, relative humidity, ventilation profiles)
control and to produce first-class results hatchers ––time point increase of humidity and maximum level of relative humidity
in integrated poultry meat production. ––time point of first chicks
The hatchery is a natural hub for commu- ––time point of chick collection
nications between separate production ––hatch window
links, because hatchery management
receives production data both from the Chick collection ––total number of saleable chicks
breeder farm and the broiler farm. ––percentage culled
––average chick weights and coefficient of variation (CV)
The basis for optimization is found (1) in ––chick yields (ratio chicken body weight and initial egg weight)
quantifiable criteria and (2) in references ––chick quality expressed in Pasgar-score units
or standards for each of these criteria
(see table). After chick transport ––temperature during transport measured with small data loggers
and first week at the ––number of dead chicks upon arrival at the farm
Reference data may be based on general farm ––weight of chicks upon arrival
standards provided by incubation consul- ––percentage of dead chicks at day 7
tants or breeder companies. Highly prac- ––weight of chicks at day 7
tical references are usually provided by ––relative growth during the first week
the hatchery itself. Hatchery managers
generally collect data on egg quality, Medication ––at the breeder farm
fertility, hatchability and first-week ––vaccination day old chicks before delivery
mortality per batch of eggs – and from
this data, hatchery specific standard
curves can be produced. Advice –– egularly compare hatchery specific
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–– ecord key data on specific forms
R data with more general reference, for
Optimization protocols are then directed designed for this purpose. example from consultants or breeder
to perform above the hatchery specific –– ecord information on medication at
R companies.
standards. A disadvantage of hatchery breeder farm and hatchery, including –– ake appropriate action if quantifiable
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specific standard curves is that structural vaccination. data falls below reference data.
failures and mismanagement may be –– efine hatchery standards with refer-
D –– nvestigate for structural failures if
I
hidden and not found. For this reason, ence to egg quality, hatchability, chick hatchery specific standards deviate
it is still advisable to compare hatchery quality and first-week mortality. below the standard curves provided by
specific data with more general reference –– ompare data from each batch with
C consultants or breeder companies.
data from consultants or companies the hatchery’s own reference data. –– lways evaluate the results of any
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periodically. measures taken to improve or alter
standards.
2 Pas Reform Academy - Putting science into practice

5. 2
Data analysis: a critical
path to improved
hatchability
In most hatcheries, the routine moni- the main cause of variability is related to Advice:
toring of incubation is based on data breeder farm management, including egg –– Define a hatchery specific standard
collected at each stage in the process. This handling at the farm and during based on the average hatchability of
is an important element of specific proto- transport. eggs set per age group.
cols for quality control and the optimiza- –– Routinely apply quality control to eggs
tion of hatchery results. For each step in In a comparison of hatchability data from received from every farm supplying the
the incubation process, quantifiable two farmhouses ‘1’ and ‘2’ (figure 1), eggs hatchery.
criteria have been defined. The hatch- were received and incubated at a specific –– Compile and use a troubleshooting list.
ability of eggs set is one such quantifiable hatchery, using standard incubation –– Reduced hatchability can be expected if
criterion, defined as the number of sale- protocols. eggs received are of poorer quality:
able chicks hatched from the total poor shell quality and hairline cracks,
number of eggs from a certain batch/ The graph in figure 1 shows that hatch- more dirty eggs, a higher number of
flock loaded in one or more incubators. ability of eggs produced by farm 1 is below floor eggs and eggs placed sharp-end
For each age group, hatchability based on the standard (overall average hatch- up, for example.
eggs set is used to determine an internal ability), except for flocks aged 41-45 wks. –– Include candling and break-out proce-
standard/reference for that group. The Conversely, the hatchability of eggs dures (e.g. 10 day candling) as standard.
internal standard is a benchmark that received from farm 2 (figure 1), incubated This will routinely identify and/or
allows the evaluation of: in the same hatchery using the same discount reduced true fertility or
1.
overall differences and variation in incubation protocols, deliver above increased early mortality as causes of
hatchery results average hatchability (grey bars) for all variation in hatchability.
2. influence of flock origin on the
the flock ages. –– Communicate the results of your inves-
v
­ ariation of hatchery results; and tigations with the breeder farm
3. influence of storage on the
the The results suggest that farm 2 pays manager, as an important start to iden-
v
­ ariation of hatchery results. greater attention to optimizing breeder tifying the cause of below average
farm management and egg handling, hatchability results.
This article focuses on variability in the both at the farm and during transit. With –– Evaluate the effects of modifications to
hatchability of eggs from one breed, such attention to these factors, farm 1 management practice on the hatch-
d
­ elivered by different breeder farms to could increase its total number of saleable ability of eggs set.
the same hatchery. The ultimate aim is to chicks and improve hatchery performance
reduce variability between breeder farms and results overall.
and thereby optimize hatchery results
overall.
90 Farm 1
The hatchability of eggs set is dependent Farm 2
not only on breeder farm management,
Mean hatchability
80 Overall average
but also on hatchery-related factors, such
as storage conditions or incubation 70
programs. Our analysis is based on data
collected over several years, from different 60
flocks incubated at one specific hatchery.
With only one breed-type to consider, we 50
30 35 40 45 50 55 60 65 70 75
can assume that factors related to incuba-
tion management are averaged for all Flock age (weeks)
flocks and breeder farms throughout the
recorded period. We may also therefore Fig 1. Percent hatchabilities of eggs (stored less than 8 days) from farm 1 and farm 2 compared to the
assume that in the following example, overall average .
Pas Reform Academy - Putting science into practice 3

6. 3
Hatching egg
quality
Hatchability and chick data are the most Egg shape Embryo
important references for optimising incu- A good quality hatching egg has a blunt The embryo floats on top of the yolk.
bation management. The age of the flock, side containing a small air cell and a In the un-incubated egg, the embryo is
number of storage days and incubation clearly recognizable sharp end. Too many visible as a doughnut-like opaque ring
program are typically included in the abnormal or misshapen eggs signifies with a translucent centre. A good quality
analysis and optimization of hatchery immaturity of the shell gland, young embryo is 3-5 mm in diameter.
results, but very often, insufficient parent stock, disease, stress and over-
a
­ ttention is paid to the quality of the crowding in the flock. Advice
hatching eggs. While external quality is –– o not take egg quality for granted
D
usually considered, there is much debate Egg shell when optimizing hatchery economics.
regarding internal quality control on a High quality hatching egg shells are –– se specific egg quality forms to record
U
regular basis. smooth, without ridges or small lumps of the quality of each batch of eggs
calcified material (pimples). The colour of received at the hatchery.
Egg quality in the broadest sense has eggs within a batch is uniform. Young –– ecord the number of good quality
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been affected by genetic selection, flocks produce eggs with thicker shells eggs and the number of eggs not
for production traits like growth, feed and when the flock ages, the shell fulfilling required standards for every
c
­ onversion, number of eggs and egg shell becomes thinner and the incidence of batch of eggs received.
quality. Breeding companies generally pay abnormal shells increases. Insufficient –– ake a minimum sample of 10 eggs to
T
less attention to egg parameters related calcium or vitamin D3 content in feed will record the quality of the embryo,
to hatchability and chick quality, which produce thin egg shells. Saline drinking albumen and yolk.
has led to increasing variability between water and high levels of chlorine will also –– ommunicate openly with your egg
C
batches of hatching eggs. cause shell-quality problems. Abnormal supplier regarding egg quality, with
white, thin-shelled eggs may indicate a the mutual aim of improving and/or
Ongoing research shows that genetic variety of diseases (IB, NCD, EDS). maintaining quality.
selection for production traits makes high
demands of breeder management with Albumen
respect to feed composition and feed Good quality hatching eggs contain a
restriction management. Genetic selection
­ higher proportion of thick, viscous
has influenced egg size, the yolk:albumen albumen with less thin albumen. The
ratio and shell quality. volume of thick albumen reduces with
Feed restriction management influences increased flock age and after storage.
the development of the reproductive tract Good quality albumen is translucent with
and the nutrients available to the growing a greenish or yellow cast indicating the
embryo from yolk and albumen. In addi- presence of riboflavin. Meat or blood
tion, with the management of breeders spots point to stress or overcrowding in
becoming more complicated, the risk of the flock.
stress, aggressive males and overcrowding
has increased - with inherent consequences Yolk
for egg (embryo) quality. The size of the yolk increases with flock
age and thus the ratio of yolk to albumen
In conclusion, if specific protocols for increases. In good quality hatching eggs,
o
­ ptimizing incubation management are the yolk has a uniform colour without any
used, it is necessary to evaluate hatching blood or meat spot. Mottled yolk points to
egg quality on a routine basis. A brief stress in the flock.
summary of internal and external para­
meters is presented hereafter.
4 Pas Reform Academy - Putting science into practice

7. 4
Uniform eggs are laid
by uniform hens
Uniformity in day-old chicks is increas- differences between birds. These differ- –– Ensure good feed composition, avoid
ingly important as a contributor to ences are mainly a reflection of variation overfeeding and apply water restriction
economic efficiency. in the development of internal organs, during the production period. These
which dictate whether the bird will be a factors help to maintain uniform egg
Producing chicks of a uniform size more - or less – efficient organism in the size.
requires two basic conditions: an opti- future. A good start from the first hour on
mized incubation process, which depends the rearing farm is the best investment
on the quality of the incubators and the for achieving the smooth development of
incubation programs - and uniformly the pullet later. Early, effective control of
sized hatching eggs, which relies upon growth, smooth development, passing
many factors linked to the breeder farm. important “check points” at six and 12
Breed, the age of the hen, the hen’s body weeks and starting the lighting program
size, feeding, diseases and the farm envi- at optimum age all contribute to the
ronment are all key factors. development of a uniform flock that will
produce uniform eggs.
In the hen’s life cycle, egg size changes
according to a natural pattern, being Advice:
smaller at the beginning of lay and –– Ensure the highest growth rate in the
becoming larger towards the end. From first week of life. High average body
the breeder flock, we expect the produc- weight at seven days – usually related
tion of as many hatching eggs as possible to high uniformity - is an indication
in an optimum size range of 50-70g. If the that all chicks started well.
hens are uniform in size and maturing at –– Avoid needing to correct body weight:
the same age, we can expect eggs laid by start feed restriction by the end of first
them to be uniform. Physical and physio- week and apply small but regular
logical development depends mainly on weekly increments of daily rationing.
rearing. In all management guides, body –– Start grading in the fourth week, to
size is described by body weight. However allow sufficient time for directing
the reproductive physiology of a small, fat extreme groups towards the common
hen is different from her tall, skinny sister target at 12 weeks.
- even if their body weight is identical. –– Aim to keep the flock strictly on target
Actual body size is related to the dimen- body weight at six and 12 weeks of age.
sions of skeleton. Breeders within one –– Assure good environmental conditions,
flock that are uniform by skeleton size regular feed increments, sufficient
and body weight at 20 weeks will respond feeding space and good disease control
similarly to programs that stimulate during the entire rearing period.
maturity. –– Start maturity-stimulating programs
when the majority of hens are ready.
Because the skeleton is fully formed by Even a uniform flock will include a
11-12 weeks of age, the first half of the proportion of birds that mature earlier
rearing period becomes an important or later. Well controlled lighting during
phase: a limited period during which rearing and not starting the stimula-
uniformity can be successfully influenced. tion program too early are basic
The first rearing week is the period when requirements.
the most intensive growth in a hen’s life
occurs – potentially leading to great
Pas Reform Academy - Putting science into practice 5

8. 5
Establishing true
fertility in hatching
eggs
If it comes to discussions on fertility The fertile, unincubated egg contains an –– f the rate of early death before the
I
two different definitions are practiced. embryo ( germinal disc or blastoderm) blood ring stage is too high, evaluate
A true fertile egg contains a well de­­veloped that developed from the fertilized oöcyte conditions during storage and the
germinal disc (blastoderm), which indicates (zygote) during egg formation in the transport of eggs - and ensure that
that the oöcyte, or zygote, was fertilized oviduct. The oöcyte is the female gamete the setter is bringing the eggs to
and an embryo developed during egg that floats on the yolk. When the yolk is i
­ ncubation temperature rapidly and
formation. Secondly, in the practice of the released in the oviduct, spermatozoa without interruption.
hatchery fertility is often based on cand­ (male gametes) penetrate the yolk
ling, whereby all clear eggs are defined as membrane, after which only one sperma- Figure 1a – Drawing showing the appearance of
unfertile and by default the rest of the tozoon fuses with the oöcyte to form the a fertile germinal disc
eggs are considered to be fertile. This fertile zygote. Finally, during egg forma-
second definition of fertility is strictly not tion in the oviduct, the zygote develops
correct since clear eggs may contain both into the blastoderm, with a recognizable
truly infertile or they may contain (fertile) Area Pellucida (AP) surrounded by an Area
embryos that died early. Opaca (AO) (figure 1a). If for whatever
reason the spermatozoa do not reach the
In hatchery practice problems with oöcyte, the egg remains infertile and the AP AO
fertility are usually first recognized during oöcyte will degenerate to form nothing
the candling procedure, when the number more than a small germinal disc. The
of clear eggs is higher than expected. infertile germinal disc is visible as a
To identify the time and the cause of compact white spot with ruffled edges
embryonic death, the hatchery manager (figure 1b). If hatching eggs are analyzed
may perform an analysis of candled eggs. on arrival at the hatchery, before incuba-
However, if candling is performed at tion, any issues with infertility can be
transfer at day 18, as is often the case, it communicated with the breeder farm Figure 1b – Drawing showing the appearance of
can be difficult to discriminate between without delay. a infertile germinal disc
true infertile eggs and eggs containing an
embryo that has died before the blood Advice
ring stage. This is because membranes –– andle eggs at transfer (day 18) as a
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from dead embryos degenerate while the standard routine.
eggs are still in the incubator. –– f the number of clears is above accept-
I
able or allowable standards, perform
By candling at days 7 - 10, it is possible to egg analysis, to distinguish between
reliably discriminate between true infer- infertility and early embryonic death.
tility and early embryonic death for two –– onsider candling followed by egg
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reasons. Firstly, because embryonic analysis between day 7 - 10, as a more
membranes formed during the first days reliable means of measuring true
of incubation can still be recognized. fertility.
Secondly, in clear eggs collected between –– nalyse a minimum of 10 fresh,
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days 7 - 10, a change in the color of yolk as un-incubated eggs on a regular basis
a result of embryonic activity is clearly when issues with fertility are suspected. Drawings reproduced with kind permission of
visible. The active young embryo trans- –– f true infertility is too high, communi-
I the publisher from Optimizing Chick Production
ports water from albumen to yolk, which cate with the breeder farm about male in Broiler Breeders, by Robinson FE, Fasenko GM
results in a whitish or light yellow ring AND female management. and Renema RA. Volume 1: Broiler breeder
around the embryo. production series, Spotted Cow Press, Alberta,
Canada.
6 Pas Reform Academy - Putting science into practice

9. 6
Managing fertility:
good breeding shows
The percentage of fertile eggs is one of Advice –– f possible, replace old cockerels with
I
the most important parameters influ- To promote enhanced fertility in the flock: new, mature males after 45 weeks of
encing the economic performance of a –– ive special attention to development
G age. Alternatively, introduce ’intra-
breeder flock. An embryo can of course and uniformity in rearing: a good start spiking’: the exchange of males
only develop from a fertile egg. in the first week, harmonic, steady between different houses. This creates
growth, maintaining body weight stan- a new social order that encourages
Fertilization takes place – and thus can dards from the beginning of the chick’s increased activity and renewed fights
only be influenced – on the breeder farm. life and especially at 11 weeks are for social position. Replace or exchange
When we consider fertility, we usually essential. at least 40 % of the males in a house.
think of the males. Yet in reality, the –– ynchronize the maturity of males and
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percentage of fertile eggs is a synthetic females. Many potential problems arise
expression describing the condition and from differences in development
activity of the males, the condition of the between the sexes. Males tend to
females - and the propensity of both mature earlier and may behave too
sexes to behave as nature intended. aggressively for successful breeding.
Sexual behaviour is closely allied to the –– bserve behaviour in the poultry house
O
contentment and welfare of the flock. in the afternoons - and be prepared to
Or put another way, fertility can be seen respond quickly. A good flock should
as a reliable measurement of the flock’s remain active and well mixed at this
overall wellbeing. time.
–– estrict water consumption at any age
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A flock performing well in respect to and take care of litter as a key factor in
fertility is one were both cockerels and determining the house environment.
hens are healthy and well developed. Both Dry, loose litter helps the birds to
groups (sexes) should be uniform, with remain clean and well feathered with
similar levels of maturity and well healthy legs. Maintain feed to water
matched in size, good feathers and ratio as 1: 1.7 - 1.9 in rearing and
healthy, strong legs. These tend to be the 1: 1.8 - 2.2 in the production period.
characteristics of flocks in a low-stress Always ensure that the house is dry
environment, with sufficient space to and warm.
promote natural behaviours and an –– void stress by limiting factors like
A
optimum diet. diseases, drastic changes of housing
conditions, feed composition or quan-
With these conditions, the inevitable tity, temperature and other basic
changes related to the advancing age of parameters. Stick to routines.
the birds will proceed synchronically. In –– timulate mating by sprinkling grain
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this sense, fertility is a trait that can be on the litter in the afternoons. Let the
regarded as a dynamic process, rather males play the role of landlords, so they
than as a single characteristic. From the have the chance to show their leading
economic point of view, the deciding position in the flock.
factor is the level of fertility that can be –– ever keep too many males in the
N
delivered in the late production period, flock. Quantity cannot replace quality.
after 45 weeks. This is also a time when It is better to keep fewer good cockerels
the most differences between the flocks than many of varying quality.
can be observed.
Pas Reform Academy - Putting science into practice 7

10. 7
Care of the egg:
from nest to farm store
A healthy, well managed breeder flock, Egg temperature at the moment of collec- Advice
receiving a balanced feed ration, will tion will vary from egg to egg, with some –– andle eggs with care at all times.
H
produce good quality hatching eggs. still holding a temperature of more than –– void shocks and jolts in handling.
A
At the moment an egg is laid, it contains 25 °C. In this case, further cooling is Remember that not only is the shell
an embryo of 30,000 - 60,000 cells. required. A newly produced egg, with a fragile, but also that inside exists an
At that point in time, each cell is already temperature close to that of the hen’s equally fragile embryonic structure!
programmed for its future function. With body (41 °C), will take much longer to cool –– ollect eggs from manual litter nests at
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the best of care, the hatching potential down when placed at the centre of a pulp least 4 times/day.
held in this delicate embryonic structure tray and covered by the next full tray, than –– ollect eggs from automatic roll away
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will be fully realised. But get it wrong – an egg placed at the side of the pulp tray. nests 2 - 3 times/day, ensuring that
and much can go amiss between nest and Ensuring that there is an adequate supply temperature on the egg transport belt
farm store. of free circulating air over the trayed eggs is 18 - 22 °C.
will greatly assist in providing uniform –– aintain a temperature of 18 - 22 °C in
M
Although the exact level of the so-called cooling. the egg collection room, to prevent
‘physiological zero’ is debated by hatchery eggs cooling down too quickly or
specialists and researchers, there is a And there are further considerations warming up again.
gene­ al consensus that embryonic
r when seeking to maintain the quality of –– aintain good nest hygiene at all
M
d
­ evelopment, which starts in the hen’s the eggs after oviposition. For example, times. Close the nests during the night,
body, will continue as long as internal too many eggs in a nest leads to an and ensure that they are opened again
egg temperature is more than 25 - 27 °C. increased incidence of hair cracks, with a before the start of egg production the
negative effect on hatchery results. Hair next morning.
Ideally, eggs should be cooled down cracks can also result from over-filling the –– void floor eggs, which should not be
A
uniformly and gradually from body egg transport belt, which causes the incubated, by good management prac-
temperature to between 18 and 25 °C in newly laid eggs to bump against each tice that starts from the rearing period.
6 - 8 hours. However the rate of cooling other. Nest hygiene, too, is important for –– llow sufficient airflow over the eggs
A
depends on several factors. Nest type in the avoidance of contamination. Floor after collection to ensure uniform
relation to frequency of egg collection eggs are a hotbed of infection in the cooling. This is best achieved by
plays an important role. Eggs produced in hatchery, affecting both hatchability and collecting eggs on setter trays. Eggs
manually collected litter nests cool down chick quality, with further reaching effects should never be packed in cardboard
very slowly to environmental tempera- also extending to increased first week boxes before they have cooled down.
ture, due to the insulation provided by the mortality and reduced performance in –– urther avoid hair cracks by using well
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surrounding nest litter. Since nest boxes the receiving farms. designed trays, without sharp edges,
are shared between 5 - 7 hens, warmth is that adequately support the eggs.
brought to partially cooled-down eggs Do not use sloppy trays and avoid
again every time another hen enters the overstacking.
nest. It is only once eggs are collected,
that they are able to cool down properly.
In automatic nests, the eggs roll away to
an egg transport belt soon after being
laid, which exposes all the eggs to a
similar environmental temperature.
8 Pas Reform Academy - Putting science into practice

11. 8
Hatching egg transport
Breeder farms are often situated away g
­ enerally recommended 18 - 20 °C can be suspension and trolleys with shock
from the hatchery. The distance between considered. Bourassa et al (2003) found absorbing wheels. Maintain access
the two sites therefore becomes an that this will produce equally good roads to farms and hatchery in good
important consideration when planning hatching results, while minimising condition.
the transfer of eggs to the hatchery. sweating during loading. –– A
dequately support eggs in well
Typically, deliveries vary from daily to not designed trays without sharp edges.
less than twice weekly, as increased Egg temperature can change rapidly when Do not use sloppy trays and avoid
storage time has a negative impact on loading, especially when air velocity is overstacking.
hatchability and chick quality. high. This mainly affects eggs on plastic or –– A
lways transport eggs small end down,
setter trays, but it is also true for eggs on to avoid loose air cells.
Egg transport is generally by truck, pulp trays - placed at the side of a buggy. –– U
se temperature loggers during
although when importing hatching eggs, Using buggy bags can delay temperature t
­ ransport to record any temperature
air transport may also be used. When changes in a situation like this. But avoid fluctuations.
flying eggs, it is worth remembering that direct sunlight on the bags! In a very short –– T
ake internal egg temperatures at
delays can occur during transfer from time, the temperature under the plastic different locations within each batch
aircraft to truck and while waiting for can rise to 5o °C! received at the hatchery, to check
customs clearance. temperature conditions during
To avoid negative affects on embryo transport.
Because hatching egg transport is vitality during transportation, sudden –– A
fter transportation, rest the eggs for
a
­ ctually a period of transition from the temperature changes, shocking and at least 12 hours before starting
farm store to the hatchery egg store, it is jolting should be avoided at all times. i
­ ncubation. Immediate setting will
important that climatic conditions are increase early embryonic mortality.
kept optimal, to maintain hatching Advice –– C
lean and disinfect all transport
p
­ otential as much as possible. Ideally, –– djust vehicle temperature to that of
A e
­ quipment prior to any egg transport,
temperature inside the truck should be the storage rooms of all supplying to avoid pathogenic spread.
equal to temperature in the farm store. farms. The hatchery should play a coor-
dinating role.
The cooling down of newly loaded eggs –– educe the risk of sweating by reducing
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should always be avoided, especially if the relative humidity in the vehicle.
vehicle is already loaded with eggs from Providing transport time is not longer
other farms. When eggs cool, the volume than 12 - 24 hours – the effect on the
of albumen and yolk shrinks, thus quality of hatching eggs is negligible.
increasing air cell volume, which will –– void sudden temperature changes
A
allow contaminated air to be sucked into during loading and unloading. Connect
the egg. the truck directly to the storage room
whenever possible or consider using
Conversely, if the temperature in the truck buggy bags – especially in situations of
is higher than in the store, the risk of high air velocity and low air tempera-
‘sweating’ (condensation forming when ture. Always avoid direct sunshine and
the colder surface of the egg is exposed to watch for unwanted condensation
humid air) increases. Even when store and forming under these bags.
truck temperatures are equal, sweating can –– nsure a constant and uniform climate
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still occur during loading and unloading, during egg transport.
especially on warm and humid days. In –– lways avoid unnecessary delays.
A
such a case, a higher on-farm storage –– void shocks and jolts during loading
A
temperature of 23 °C instead of the and transport – use trucks with good
Pas Reform Academy - Putting science into practice 9

12. 9
Impact of hairline-
cracked eggs on
hatchability and chick
performance
In general, good quality eggs are selected Good quality eggs Hairline-cracked eggs
and placed for incubation. This means
that only clean eggs with shell intact Hatchability (%)
should be placed on the setter trays. – Eggs set 74.4 50.5 Significant (P 0.05)
Dirty or floor eggs and eggs with visible – Fertile eggs 80.9 56.4 Significant (P 0.05)
cracks are removed and not placed. Eggs
with hairline cracks might often not be Chick weight
recognised and will, consequently, be – Weight (g) 45.0 43.5 Significant (P 0.05)
placed in the setter trays and incubated. – Relative weight (% of eggs set) 69.9 67.5 Significant (P 0.05)
In cracked eggs, the shell is broken and Growth performance
the underlying membrane is ruptured – – D14 body weight 293.5 298.9 Not significant
leading to dehydration and the death of – Mortality 2 7.5 Significant (P 0.05)
the embryo. However eggs with undam-
aged membranes but broken shells are Egg weight loss in the setter (%) 13.4 17.02 Significant (P 0.05)
defined as having hairline cracks – and
these are often placed because unless Embryonic mortality (%)
candled, they look like good quality eggs. – Early (1 - 7d) 7.9 13.9 Not significant
– Mid (8 - 14d) 0.0 2.9 Significant (P 0.05)
A study of the incubation of good quality – Late (15 - 21d) 4.6 15.5 Significant (P 0.05)
hatching eggs versus those with hairline – Cull 5.3 6.2 Not significant
cracks produced the results shown in the
summary. In this experiment, eggs from Contaminated or broken (%) 1.2 5.2 Significant (P 0.05)
five commercial flocks of various strains
were candled and an equal number of Reference: Barnet et al. (2004). Hatchability and Early Chick Growth: potential of broiler breeder eggs
hairline-cracked and normal eggs were with ­ airline cracks. J. Appl. Poult Res. 13: 65 - 70.
h
incubated for 21 days. Eggs were identified
as having a hairline crack if the crack was The study concludes: Advice
visible by candling, but not apparent 1 Setting eggs with hairline-cracks –– o not set hairline-cracked eggs.
D
when examined normally. s
­ ignificantly reduces hatchability. –– andle egg samples from batches
C
2 Chicks hatched from hairline-cracked transported to the hatchery on a
eggs demonstrate higher mortality regular basis to evaluate the incidence
during a 14 day growing period. of hairline-cracked eggs.
3 Egg weight loss during the setting –– ecord the number of eggs with
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period increases significantly in hair- hairline-cracks.
line-cracked eggs, producing smaller –– f the frequency of hairline-cracked
I
chicks as a consequence. eggs is unsatisfactory, investigate and
This however has no effect on day 14 eliminate possible causes.
weight. –– void the use of plastic trays with
A
4 Compared to good quality eggs, sharp edges for the transportation of
a significantly higher incidence of eggs, as these are likely to be a major
contaminated and broken eggs was cause of hairline-cracks.
found after incubating eggs with
hairline-cracks.
10 Pas Reform Academy - Putting science into practice

13. 10
Pre-storage incubation:
a matter of routine?
The care of hatching eggs during storage Eggs scheduled for storage for more than Guidelines
– at the farm, in transit or at the hatchery seven days after production benefit most To assess performance benefits and
– is an important aspect of hatchery from pre-storage incubation establish pre-storage incubation protocols
management that aims to preserve the However, many questions, mainly in the hatchery:
vitality of the embryo. concerning timing and duration, continue 1. Egg selection: per egg type, three trol-
to surround the adoption of pre-storage leys for pre-storage incubation with
With optimum temperature and relative incubation in routine management one trolley (same batch) for the control.
humidity, hatching eggs can generally be practice. 2. Disinfect: if the eggs are incubated in a
stored for one week without significantly normal routine setter.
reducing hatchability or chick quality. Considerations for the practice of 3. re-storage incubation: place trolley(s)
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Eggs stored for longer than this are p
­ re-storage incubation with (disinfected) eggs in a running
known to benefit from lower storage Pre-storage incubation is only beneficial if setter at incubation temperature.
temperatures (12-14 °C) (Fasenko, 2007; the embryos in the eggs are in a very early Incubate the eggs for 3, 6 and 9 hours.
personal experience). stage of development. For example: if Control eggs stay at storage
nest temperatures are high and the eggs temperature.
Pre-storage incubation, i.e. incubating stay in the nest too long, the embryos 4. eturn pre-storage incubated eggs to
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hatching eggs before they are placed in may develop beyond the storage resistant the storage room (with control eggs)
the storage room, is a new approach to stage, when pre-storage incubation will for at least seven days before starting
storage management that aims to increase early embryonic mortality. the normal incubation cycle.
develop the embryo to the so-called hypo- Small-scale experiments will help identify 5. Run normal incubation with both the
blast stage: a stage of embryonic develop- the best timing and length of pre-storage pre-storage incubated eggs and the
ment that is better able to survive incubation for your own hatchery and egg control eggs.
storage. types (see below). To assess results in your 6. valuate: compare hatchability - pre-
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own hatchery: storage incubated eggs vs. control eggs.
According to Fasenko (2007), broiler –– Place eggs for pre-storage incubation 7. epeat this experiment with eggs from
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hatching eggs reach the hypoblast stage on setter trays in setter trolleys, to at least three different flocks.
after six hours of pre-storage incubation, ensure uniform egg temperature 8. valuate all results. If positive, adopt
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turkey embryos after 12 hours. during incubation. pre-storage incubation routine as indi-
Layer hen hatcheries have reported –– Do not incubate eggs on paper trays or cated by results.
improved performance, seeing 3-7 % more in boxes. This guarantees heteroge-
females after pre-storage incubation for neous egg/embryo temperatures,
3-6 hours, when eggs are stored for more resulting in high levels of early
than 11 days (Lohmann Tierzucht, mortality.
Management Guide). –– Disinfect eggs as long as pre-storage
incubation is performed in a setter
In the broiler industry, positive pre- located in the setter room (‘clean area’).
storage incubation results show at least a Ideally use a specific incubator, located
one per cent increase on expected hatch- close to the egg storage room.
ability, when the eggs undergo pre- –– Pre-storage incubation can be applied
storage incubation of 3-6 hours on arrival when eggs arrive at the hatchery 3-4
at the hatchery (Fasenko et al., 2001; days after production and are sched-
Fasenko, 2007). uled for more than 4 days extra storage
at the hatchery.
Pas Reform Academy - Putting science into practice 11

14. 11
Storage of hatching
eggs
Egg storage is the time between oviposi- temperature’, but more research is needed –– llow extra incubation time for stored
A
tion (laying) and the start of the incuba- before it can be concluded that suggested eggs: on average one hour extra for
tion process for hatching eggs. Optimal temperature ranges should change. each additional day after an initial
hatching results and chick quality can be storage period of three days.
achieved if eggs are set after an initial Advice
adaptation period of about 1 to 2 day(s). –– llow eggs to cool gradually, from the
A
This allows carbon dioxide to be released hen’s body temperature to between Storage duration Temperature Relative
from the egg, which increases albumen 18 - 25 °C in 6 - 8 hours; do not place (°C) humidity (%)
pH from 7.6 at oviposition to pH8.8 – 9.3. them in storage (especially not if
Yolk pH remains virtually constant around already placed on setter trays) too 0 - 3 days 18 - 21 75
pH6.5, so that the embryo, situated on the quickly after lay.
yolk, is exposed to a pH-gradient. This –– inimize the duration of storage to
M 4 - 7 days 15 - 17 75
optimises early embryonic development. counter negative effects.
–– e aware that storage starts on the day
B 8 - 10 days 10 - 12 80 - 88
Storing eggs beyond two days leads to of egg production, not necessarily the
loss of hatchability and reduced chick same as the date of receipt at the More than 10 days 10 - 12 80 - 88
quality. An epidemiological study of Dutch hatchery.
hatchery data (Yassin et al. 2008) showed –– abel each batch of eggs with its actual
L
that, on average, each extra day of storage date of production.
at the hatchery before the seventh day –– aintain optimal climatic conditions
M
reduced hatchability by 0.2 %, rising to during storage (see table), taking the
0.5 % after the seventh day. planned duration of storage into
consideration.
Day-old-chicks from stored eggs show a –– onsider having two separate storage
C
higher incidence of ‘black navels’. Tona et rooms, each with specific climate condi-
al. (2004) found that Cobb broiler chicks tions, if storage time is not constant.
hatched from eggs stored for seven days –– tore eggs small end up, starting on the
S
weighed over 200 grams less at slaughter first day of storage, if hatchery plan-
age, than chicks from fresh eggs. ning dictates that eggs must be stored
Differences in body weights emerged at more than 10 days. Alternatively, if eggs
14 days post hatch and increased until are stored on setter trays (blunt ends
slaughter age at 42 days. up), turn them 90° once daily.
–– hoose the upper limit of recom-
C
In recent research by Pas Reform Academy, mended temperature ranges if there is
eggs from three different broiler breeder a risk of ‘sweating’ when eggs are
flocks of different maternal ages (30, 38 removed from storage. Gradual
and 50 weeks) were stored at 18 - 20 °C warming in a ‘pre-processing room’ at
and 12 - 14 °C for 7 and 11 days, both at 75 % an intermediate temperature may be
relative humidity. Storage at the lower necessary.
temperature resulted in a higher average –– osition eggs in storage to avoid direct
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hatchability of 0.6 % (experiment 1: 7 air flow from egg room coolers and/or
days), 1.1 % (experiment 2: 7 days) and humidifiers - and sufficiently removed
3.2 % (experiment 3: 11 days). These results from the heating system.
support the view that ‘the longer the –– o not place eggs directly against the
D
storage period, the lower the storage wall or on the floor in the storage room.
12 Pas Reform Academy - Putting science into practice

15. 12
The importance of
preventing ‘sweating’
eggs
‘Sweating’ of eggs refers to the phenom- This of course will lead to increased Advice
enon of condensed water sitting on the embryonic mortality, ‘exploders’ and –– f the risk of sweating is high, pre-warm
I
egg shell surface. This occurs when cold infected day-old-chicks (increased first eggs gradually at least six hours prior
eggs are suddenly exposed to a higher week mortality). to removing them from the egg storage
environmental temperature. The warm air room. This is achieved by switching off
with a certain moisture content cools Clearly moisture on egg shells should be the egg room cooler several hours
down rapidly directly around the colder prevented. Egg sweating is prevented before taking out the eggs. It is impor-
eggs. Since cold air contains less water when the difference in temperature tant to realize that not all eggs warm
than warm air, relative humidity will between the egg storage room and up at the same, uniform speed, espe-
increase until the air is saturated. And at ‘the outside’ (e.g. loading platform of the cially with low air circulation and if
that moment, condensation will take truck, egg traying room, setter) is small stored on pulp trays and stacked closely
place on the cool egg surface. and the ‘outside’ humidity is low. together.
–– tore at a higher temperature, combined
S
The term ‘sweating’ is, if taken literally, The table below can be used to predict with a shorter storage period.
misleading, because the water on the whether sweating will occur if no –– onnect the truck picking up the
C
shell does not in fact come from within a
­ dditional measures are taken. For a wider hatching eggs directly with the storage
the egg. The same physical process is seen range of temperatures and humidities, a room to minimise any temperature
when a bottle of water is removed from a so-called ‘Mollier’ diagram or psychometric diffe­ ences from the outside
r
refrigerator on a warm summer day. graph provides a useful tool. environment.
–– nsure that the climate in the truck is
E
Sweating of eggs should be avoided There is also a risk of eggs sweating if the same as in the egg store.
because moisture on the shell surface they are set too cold in setter that is –– aintain humidity below the levels
M
weakens the egg’s natural defence already running to temperature, as is the indicated in the table.
m
­ echanisms, providing as it does an ideal case in multi-stage incubation practice. –– rior to placement in the setter, place
P
environment for the growth of micro- the filled setter trolleys at a room
organisms, and further facilitating their temperature of 25 °C with good air
penetration through the shell pores. circulation for several hours. This pre-
warming of the eggs before setting is
Once inside the pores, micro-organisms particularly important when using
are protected from most routine egg sani- multi-stage incubation.
tising operations, therefore presenting a
potential risk for contamination. Bacteria Eggs will ‘sweat’ if the relative humidity (% RH) outside the storage room is higher than:
and fungi which manage to pass through
the shell membranes will multiply at a Temperature Temperature outside the storage room
rapid rate when they are exposed to incu- of storage
bation temperature, because the defence room1 15 °C 18 °C 21 °C 24 °C
mechanism in the albumen is no longer
able to protect the growing embryo. 21 °C … … … 85 % RH
18 °C … … 83 % RH 71 % RH
16 °C … 89 % RH 74 % RH 60 % RH
11 °C 74 % RH 64 % RH 53 % RH 44 % RH
1 Assuming that the temperature of the eggs equals the temperature of the egg storage room.
Pas Reform Academy - Putting science into practice 13

16. 13
Formalin-free hatching
egg disinfection: an
achievable goal!
Disinfecting hatching eggs is a critical Depending on the type of disinfectant A further and more recent development is
control point (CCP) in the poultry produc- used, between five and ten litres of disin- the sustainable, onsite production of a
tion chain, aimed at reducing the intro- fectant, in solution according to the highly effective, non-toxic disinfectant
duction of pathogens into the hatchery manufacturers’ instructions, is sufficient that is known to have no adverse side
for the production of healthy to disinfect 115,200 eggs loaded on 24 effects with continued use. Electrical
day-old-chicks. setter trolleys. Complete disinfection can Chemical Activation (ECA) of a saturated
be achieved in less than one hour, sodium chloride solution, found its origins
Properly carried out, fumigation with depending on the number of nozzles in the Soviet Space Program several years
formaldehyde gives excellent disinfection used, with the further benefit that ago. It has been further developed by
results at relatively low cost – and has existing (formalin) fumigation rooms can Dutch company Watter BV, such that it
become a common method of disin- be adapted to deliver Low Volume Misting now delivers a disinfectant solution in a
fecting hatching eggs worldwide (see without major renovation. reliable and repeatable manner.
Cadirci (2009) for a detailed review).
However, contra-indications for human With Low Volume Misting, the egg surface This disinfectant, which contains active
health and the environment have already becomes slightly wet, which is a good chlorine compounds, different hydroxyls,
prompted several countries to ban the use indication that the disinfectant is properly hydroxyl radicals and oxygen compounds,
of formaldehyde and, as pressure grows distributed. While it is true that eggs has been extensively trialed by several
to discontinue its use, more are expected should not get wet by water eg. rain, Dutch hatcheries, who report excellent
to follow. humidifiers or condensation, which results, with the additional benefits of
provides a transport medium for bacteria user, material and environmental friendli-
However, there are several good alterna- to enter the egg through pores in the ness. Production costs are extremely low.
tives, both for disinfectants and in shell, it is a myth that eggs should not get
methods of application. Applying disinfec- wet when using a suitable disinfectant, Whichever route the hatchery chooses, it
tant as a gas, as with fumigation, is which will kill micro-organisms and pres- is clear that formalin-free hatching egg
advantageous because many eggs can be ents no threat. disinfection is achievable in the hatchery.
disinfected simultaneously, with the
added assurance that the entire surface of Disinfectants containing quaternary Advice
each egg is properly treated. ammonium compounds combined with –– Disinfect shell-clean hatching eggs
glutaraldehyde and hydrogen peroxide in only.
The same quality of disinfection can be combination with peracetic acid have –– Ensure good distribution of the
achieved by Low Volume Misting, which been used successfully for hatching egg d
­ isinfectant over the entire surface of
produces a very fine fog with a maximum disinfection. Overdosing should be every egg.
droplet size of 10 microns. Hatcheries avoided, as this may either cover the –– Evaluate the type of disinfectant,
employing this method report good pores, which could hamper weight loss d
­ ilution rate and quantity not only by
results with air supported nozzles, while and gas exchange during incubation, or reduced numbers of micro-organisms,
noting that to achieve even distribution damage the protective cuticle. but also by effects on weight loss
of the disinfectant over eggs that are during incubation and the effect on
tightly packed on setter trays loaded in cuticula, hatchability and chick quality.
setter trolleys, some fine-tuning of air –– Consider the effects of the disinfectant
pressure and the supply-pressure and on personnel, equipment and your
–speed of the disinfectant solution is environment over the long-term.
required. Trials are currently underway to
find a more robust, less sensitive type of
nozzle.
14 Pas Reform Academy - Putting science into practice

17. 14
The effects of setting
eggs small end up on
hatchability and chick
performance
Eggs are incubated in setter trays for most Flock Large end up Small end up
of the incubation period. Three days
before hatch, the eggs are transferred to A Hatchability (%) 97.6 79.5
hatcher baskets. In the setter trays the Cull (%) 0.0 3.6
eggs are placed vertically with the air cell Grade-A chicks (%) 97.6 75.9
(large end) up, while the eggs lie horizon-
tally during hatching. B Hatchability (%) 96.9 71.8
Cull (%) 3.0 4.3
In normal development, the embryo Grade-A chicks (%) 93.9 67.5
begins to turn to its position along the
long axis of the egg at day 14. At day 18, C Hatchability (%) 100.0 84.0
the beak is turned to the air cell and Cull (%) 2.0 4.0
covered by the right wing. In this position Grade-A chicks (%) 98.0 80.0
the embryo can penetrate the inner cell
membrane to gain access to the air in the Reference: Bauer F., Tullet SG and Wilson HR (1990). Effects of setting eggs small end up on hatchability
air cell – after which breathing starts. and posthatching performance of broilers.
This normal sequence of events is The incidence of eggs set upside-down is Advice
disturbed when the eggs are placed with largely dictated by human error and not –– heck each batch of eggs for the
C
the air cell down and the small end up. In by the shape of the eggs. Great variation i
­ ncidence of eggs placed small end up
this scenario, the embryo still turns along between trays in the number of eggs (upside down).
the long axis of the egg with the head up placed upside down was observed: some –– ecord the number of eggs placed
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– but now, the head is positioned in the trays had none, while others had 10 - 12 upside down.
small end of the egg – away from the air eggs placed small end up. Hatchability of –– f the frequency of eggs placed upside
I
cell. The embryo may die because the eggs set small end up decreased by down is unsatisfactory - investigate
initiation of normal lung breathing is 16 - 27.3 per cent. The percentage of non- and remedy the reasons for misplace-
hampered or even blocked. viable chicks from eggs set small end up ment of the eggs.
increases, but varies between different –– f the eggs are routinely set in setter
I
Hatchability of eggs placed with small batches of eggs. A hatchery loses 0.2 per trays at the breeding farm, communi-
end up decreases from 12 - 30 per cent cent of sellable chicks for each 1 per cent cate the benefits (profit) of good
when compared to hatchability in eggs of fertile eggs placed with the small end p
­ lacement and place responsibility for
set large end up. However, once hatched up in a setter tray (Bauer et al, 1990). ensuring that eggs are placed correctly
from an egg set small end up, the perfor- with farm personnel. Breeder farm
mance of chicks is no different to that of personnel should all be aware of the
chicks hatched from eggs placed large fact that the hatchery loses 0.2 per cent
end up. The table on this page shows a of sellable chicks for every 1 per cent of
summary of data collected from commer- fertile eggs placed small end up in a
cial hatcheries. Over 3,600 eggs were setter tray.
candled from each flock. The percentage of
eggs placed small end up varied between
0.29 - 3.4 per cent, irrespective of the
shape of the eggs.
Pas Reform Academy - Putting science into practice 15

18. 15
The benefits of ­
single-stage incubation
to food safety
Typically, papers on single-stage New eggs are placed regularly, once or The whole production chain is controlled
i
­ ncubation focus on the benefits of all-in- twice a week. In the multi-stage system, by strict legislation for chain manage-
all-out incubator management from the the climate is controlled by the eggs. ment (tracking and tracing) and hygiene.
points of hatchability (number of chicks) The integration of a single-stage hatchery
and uniformity (chick quality). Much less Conversely, single-stage incubation is in such poultry production systems is a
is written about the positive impact of based on climate control technology, simple task, because the principle of all-
single-stage incubation management on geared specifically to meeting the in-all-out makes the tracking and tracing
hatchery hygiene. Yet when food safety is demands of the growing embryo. The of different batches of eggs easy.
such a pivotal issue for the modern incubator climate controller provides the
hatchery, from tracking and tracing to embryo with heat and cooling as required. To fill the multi-stage incubator, a batch
physical hygiene and biosecurity Set points of temperature, relative of eggs from one supplier must often be
measures, this is a major benefit that humidity and ventilation are adjusted, separated into smaller batches and placed
should not be overlooked. according to embryonic age. Eggs are in different setters. This complicates
placed in empty, disinfected incubators. tracking and tracing, making errors more
Background likely to arise.
Hastings’ invention of the forced-draught Single-stage hatchery management
incubator in 1911 was a great step forward may also be based on the daily routine. And the multi-stage incubator is never
in the technology of large scale incuba- Single-stage incubation programmes, completely empty - making thorough
tors. Cooling in these early, forced-draught once set-up for different eggs types, can disinfection almost impossible. Single-
machines was mainly based on air cooling be applied routinely. stage incubation, however, allows for the
to prevent the eggs from overheating, and machines to be thoroughly cleaned and
very little on water cooling. The air Hygiene and food safety disinfected every 18 days (between
temperature was controlled at a fixed set The climate in a multi-stage incubator is batches of eggs).
point, by balancing the heat produced by controlled by levels of heat production in
older stage embryos with the heat- ‘older’ eggs, which heats the freshly Advice
absorption demands of the younger placed eggs by air transfer. However, To enhance food safety at hatchery level
embryos: so-called multi-stage incubation. ‘older’ eggs are not only a source of heat. in the production chain, the single-stage
They are also a source of micro-organisms, incubation process delivers benefits not
That innovation has been with us for for example bacteria or fungi, which can available through multi-stage incubation
almost 100 years. And despite an explo- contaminate the ‘younger’ eggs. Add to by:
sion in the physical scale of commercial this the risk of exploding or gaseous eggs, –– reventing cross-contamination from
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hatcheries, and massive advancements in and contamination early in life may have older to younger egg batches, because
climate control technology - simplicity of lasting implications, leading to contami- eggs of different ages need not be
incubator management, slow replace- nated broilers with decreased perfor- mixed.
ment rates for hatchery equipment and mance, higher mortality - and ultimately –– acilitating the simple identification,
F
low labour costs in many countries mean contaminated meat products. tracking and tracing of each hatch.
that multi-stage incubation is still –– nabling thorough cleaning and
E
favoured by many hatcheries today. Thus, from a hygiene and food safety d
­ isinfection between hatch cycles.
point of view, the multi-stage incubator
Management becomes a source of contamination,
The simplicity of multi-stage management which may lead to economic losses at
stems from the fact that new, unincubated hatchery level due to lower hatching rates
eggs are placed alternately with eggs and chick mortality.
containing older, heat producing embryos.
16 Pas Reform Academy - Putting science into practice

19. 16
How hatchery
management changes
when starting single-
stage incubation
Management in a multi-stage hatchery is incubators can also be cleaned after each –– ollow manufacturer’s guidelines care-
F
based on a daily routine of setting eggs incubation cycle and thus meet high fully when starting the first incubation
according to a strict setting schedule per hygienic standards of today’s food cycle in the single-stage incubator.
setter type. The common principle for production industry. –– eep records for each incubation cycle,
K
establishing a setting schedule in a multi- per egg type used and showing the
stage incubator is based on the need to Often, the transition from multi-stage to different management steps taken per
transfer metabolic heat from more single-stage incubation is initiated by the type.
d
­ eveloped embryos to the less developed, replacement of aged multi-stage incuba- –– se data with respect to hatchability,
U
heat-demanding embryos in the early tors by new single-stage equipment, incubation time and chick quality from
stage of embryonic development. without an awareness that hatchery recording forms to fine-tune your
management too will need to be adjusted. i
­ ncubation programs.
Embryo temperature in a multi-stage Management in a single-stage hatchery is –– rain hatchery personnel so that they
T
i
­ ncubator is mainly controlled by the certainly not based on a routine, but are fully advised regarding the different
pattern of alternating ‘old’ heat producing rather adjusted to accommodate the management steps required when
embryos and ‘young’ heat demanding needs of a specific egg type. Consequently, using single-stage practices.
embryos. The incubators are filled hatchery managers need to learn about –– ighlight the need for change: make
H
according to the direction of the airflow variation in needs of embryos from sure hatchery personnel understand
in that specific make or model of different egg types, as defined by strain, that single-stage management requires
i
­ ncubator. In addition the temperature flock age and the duration of storage. a different approach to multi-stage
controller is fixed at a specific set point. management to succeed.
Embryo temperature is thus only Advice
supported approximately in multi-stage –– lan size of setters in accordance with
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incubators. size of batches of eggs. A batch of eggs
is the total number of eggs produced on
Management in the multi-stage hatchery a specific day by one flock in one farm.
cannot accommodate egg quality or the –– reate an overview of the egg types
C
needs of the growing embryo. However, incubated in your hatchery.
it has becoming increasingly clear that –– o not mix different batches of egg
D
today’s modern breeds need a more accu- types. If separating egg types for
rate approach to incubation to achieve i
­ ncubation is not possible:
high numbers of good quality chicks that • setters with batches of eggs that
Fill
fully realise their genetic potential have similar characteristics with
(Fairchild et al, 2007). Furthermore, the respect to strain, flock age and days
multi-stage incubator cannot easily be of storage.
cleaned - because it is never empty. • Avoid filling one incubator with eggs
from flocks more than 5 weeks apart
For these reasons, more and more hatch- in flock age.
eries are making the transition from • Avoid filling one incubator with eggs
multi-stage to single-stage incubation from one flock but with more than
management. 5 days’ storage difference.
• the incubator has to be filled with
If
Single-stage incubation runs specific more than one batch of eggs, do not
i
­ ncubation programs such that the combine fresh eggs with eggs stored
climate in the incubator is programmed for more than 5 days.
to match the specific needs of the
d
­ eveloping embryos. Single-stage
Pas Reform Academy - Putting science into practice 17