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International Hatchery Practice Volume 33 Number 4 (2019) Practical information for better breeding and hatching SALMONELLA The importance of prevention in laying hens INCUBATION Ensure the correct egg setting to maximise output INFECTIOUS BRONCHITIS Minimising the impact on breeder productivity BREEDER NESTS We look at options from around the world TURKEYS Using the right breed for the right market HOUSING The ideal environment to maximise laying potential
PUBLISHED BY
Positive Action Publications Ltd
PUBLISHER & EDITOR
NIGEL HORROX
fertilethoughts
neh@positiveaction.co.uk
T
oday, should breeder and They are our industry’s dinosaurs and
MARKETING TEAM hatchery managers around the they have the potential to hold up
COLIN FOSTER world be known as livestock, progress.
cf@positiveaction.co.uk equipment or people managers Our staff are changing. They are
ALISON BURDASS instead? Interestingly, most people becoming better informed and
ab@positiveaction.co.uk
would say they should be known as better educated. Today, most staff
CLAIRE FUSSEY
claire@positiveaction.co.uk one of the first two options, with have a mobile phone and by means
STEPH WEIGHTMAN most identifying hatchery managers of it, or another route, have access
steph@positiveaction.co.uk as equipment managers. Some to the internet.
would probably cover their options What they do not appreciate is
PRODUCTION and say they are a combination of that there are people in this medium
SARAH DOVE
sarah@amneh.co.uk livestock and equipment managers. who will consciously, or perhaps
Interestingly, and somewhat unconsciously, manipulate them and
DESIGN & DIGITAL worryingly, people managers usually their views. Why not create a closed
MATTHEW BAKER comes a poor third among the intranet site for your hatchery and
bacca@amneh.co.uk
answers. As the number of staff breeder staff? This will give you and
SUBSCRIPTIONS increase per unit of output, people your senior managers an extremely
SALLY WALKER management skills appear to remain effective management tool. Make
sw@positiveaction.co.uk static or even in decline in our use of it to motivate and educate
managers. your staff!
ACCOUNTS This probably relates to the fact What we want in today’s managers
ANNE SMITH
accounts@positiveaction.co.uk that many of these farms and are individuals who are aware of the
hatcheries are in Africa and Asia sensitivities of other people and
The copyright for material appearing in International
Hatchery Practice is held by Positive Action Publications Ltd.
where farm staff and managers have their unique needs, aspirations and
Production of editorial material, in whole or part, from this been influenced by their colonial goals. If we can satisfy these we will
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holder. Positive Action Publications, its editors and the predecessors, many of whom saw get motivated staff who want to
contributors accept no liability for the contents of
International Hatchery Practice and the views expressed in it
staff simply as a tool. make things work.
are statements and opinions of the authors and do not As a result of this, we see We need to be sensitive to our
necessarily constitute representations of fact.
individuals who still think that ‘if staff and when we see somebody is
The publishers accept no liability for late or non-delivery. that management style worked for operating below par, we need to
No refund can be made after fulfilment has begun.
them, it should work for me’. It will communicate with them and find
International Hatchery Practice (ISSN 0959 9363) is not! These individuals are in the out what their problem is.
published eight times a year (January, March, April, May, July,
September, October and December) by Positive Action wrong job, in the wrong time zone. Then, we must help them. n
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International Hatchery Practice, Positive Action Publications, Cover Picture: (photo courtesy of Hendrix Genetics)
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International Hatchery Practice • Volume 33 Number 4 3
The world’s unique technical
and practical publication for
everyone involved in poultry
breeding and hatching
worldfocus An executive summary of key international issues
USA
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published 8 times a year and your
subscription includes a free digital edition Routine surveillance finds LPAI in Californian duck breeder
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discounts available comprehensive epidemiological investigation and have implemented enhanced surveillance
and testing related to this recent isolation. Results are also awaited on two additional farms.
Subscribe online today @
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or contact
SALLY WALKER
sw@positiveaction.co.uk
USA
Californian Newcastle disease spreads to Arizona!
For details of our digital edition contact:
Virulent Newcastle disease has been found in an Arizona chicken flock. The disease was
SHARON WILSON
sharon@positiveaction.co.uk found near Flagstaff in a backyard flock of eight birds. Tests have shown the strain is part of
the Southern California outbreak which began last year. The Department of Agriculture is
PO Box 4, Driffield, endeavouring to control spread by setting up a 1km surveillance zone around the infected
East Yorkshire YO25 9DJ, farm. One theory about the source is that an owner brought back birds from California to
England. avoid quarantine. Backyard poultry owners have been advised to practice extra biosecurity
Tel: +44 1377 241724 precautions when going from one person’s flock to their own and not to share feed
Fax: +44 1377 253640 between flocks. People and feed movements are two easy ways to spread the disease.
Y^
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Contact us for more information The number of cases of Newcastle disease in backyard chickens in California has now
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reached over 430 since May 2018 and has affected at least three commercial egg layer
operations. A further $45 million has been made available from central funds for APHIS and
partners to address the ongoing situation. Their primary objectives are to contain the
spread of Newcastle disease and to keep it out of commercial flocks. This funding will
allow APHIS and the California Department of Food and Agriculture (CDFA) to strengthen
their joint efforts to stop the spread of this disease and prevent it from affecting additional
commercial flocks. Currently, trade impacts are minimal but this could always change.
International Hatchery Practice • Volume 33 Number 4 5
6 International Hatchery Practice • Volume 33 Number 4
The importance of
preventing salmonella
in laying hens
S almonellosis belongs to the
most important foodborne
zoonoses throughout the
world. According to the European
Food Safety Authority (EFSA), each
greatest hazard to public health
include raw meat and raw meat
products, unpasteurised milk
products, eggs and products
containing raw eggs, sprouted seeds
year over 90,000 salmonellosis cases and fish products. The main
are reported in the European Union. symptoms of salmonellosis include
While for the United States, the fever, diarrhoea and abdominal
Center for Disease Control and cramps. In most cases people
Prevention (CDC) estimates that infected with salmonella do recover,
about 1.2 million illnesses and 450 unfortunately in less than 0.1 % of
deaths occur every year. the cases it can result in death.
by Freek Thomassen, Salmonella and its relation
Hendrix Genetics. to poultry
www.hendrix-genetics.com
The 1999 report from Steinback and
Hartung revealed that approximately mostly associated with the program in place, one that has been
The CDC estimated that food is 60-65% of human infections were consumption of eggs, egg products adjusted to the environmental,
the source for about one million caused by salmonella arising from and meat. regional and organisational
illnesses in the USA. For Europe, a poultry, eggs and egg products. Their When looking at poultry, conditions of your operations.
significant decreasing trend of research also showed that this was S. enteritidis was found in 59% of the A well-defined and structured
salmonellosis has been observed nearly exclusively linked to cases. The second most detected biosecurity plan is needed so that
between 2008 and 2016. However, Salmonella enteritidis. S. enteritidis serovar, S. infantis, was found in less the daily routines are steered in a
the recent Salmonella enteritidis is markedly associated with laying than 10% of the cases, and comprehensive way.
outbreaks contributed to a change in hens, broilers and broiler meat (Fig. 1 S. typhimurium was found in around Often biosecurity is considered an
this decreasing trend in both humans and Table 1). 5% of the cases. The other serovars additional expense, but we, as a
and poultry. The European Union summary reached percentages between 1.5% breeding organisation, are more than
report on trends and sources of and 4.4%. able to see that it pays off fully! Not
zoonoses, zoonotic agents and only for the general health of your
What is salmonella? foodborne outbreaks in 2016 reveals birds, but also for the health and,
that in 2016, 1.47% of the EU breeding How to control salmonella in especially in the case of salmonella,
Salmonella is a bacterium that can flocks were tested salmonella your birds? the safety of the consumers.
cause an illness called salmonellosis positive (versus 1.42% in 2015) and Below we list the most important
in humans. Salmonella is commonly 3.71% of adult laying hens flocks When you look at the above strategies that should be
found in the intestines of healthy were tested positive (versus 2.67% in numbers, you can clearly see that implemented to prevent the spread
birds and mammals. In humans, the 2015). S. enteritidis seems to play a there is a strong need to control of salmonella.
risk of a salmonella infection is dominating role in the European salmonella in your birds. For poultry
associated with the consumption of salmonellosis; in 48.5% of all the producers, the first aim is to prevent l Hygiene and disinfection:
contaminated food. cases, isolates that belong to the salmonella bacteria from This is the most obvious strategy, but
The food categories posing the S. enteritidis were reported and it is entering their operations. easy to miss. All buildings and
When present, the aim is to equipment must be cleaned and
prevent salmonella from entering disinfected before the new flock
Fig. 1. Reported isolations of Salmonella enteritidis from animals in EU the food chain via the eggs or the arrives. The effectiveness of cleaning
member states and other reporting countries, 2011-2016. meat they produce. The only and disinfection should be checked
successful control of salmonella via environmental sampling.
infection in your birds starts at the Intensive cleaning and disinfection
n Total isolations n Isolations in Gallus gallus hatchery and farm level! are needed when the previous flock
2000 Strict sanitary measures need to be is found to be salmonella positive!
taken so that hatching eggs, day-old The aim of cleaning and disinfection
1600
Reported cases
chicks, feed, water, litter, the barns is to cut the circulating infection
1200 or rodents are not the source of a chain after depopulation of the
salmonella infection. Environmental farms if you make use of the ‘all-in,
800 sampling has been proven to be a all-out’ principle.
highly effective tool in detecting A well-managed barrier system
400 salmonella and to be used for the around the hatcheries and barn
verification of your cleaning and houses should also involve proper
0
2011 2012 2013 2014 2015 2016 disinfection. cleaning and disinfection steps to
It is highly recommended that you prevent possible introduction of
have a proper working biosecurity Continued on page 9
International Hatchery Practice • Volume 33 Number 4 7
Continued from page 7 Animals 2011 2012 2013 2014 2015 2016
salmonella from outside via vehicles,
farm visitors, boots, etc. Gallus gallus (fowl) 1381 1533 902 954 1237 852
l Feed and water: Other animals 50 20 120 45 22 607
It is known that feed can be an Cattle 23 62 60 148 170 10
important source of contamination
with salmonella. Grains and animal Other poultry or game birds 5 96 16 141 6 12
meal are common sources of feed
contamination, as well as Geese 23 60 63 27 27 21
environmental dust. Turkeys 34 16 21 15 43 41
Pelletising feedstuffs, or heat
treating the feed will destroy almost Ducks 8 39 32 24 33 28
all bacteria present in feed, but there Pigs and wild boars 18 17 34 20 19 17
is always the chance of
recontamination. Cats and dogs 8 20 3 2 10 10
Recontamination of the feed can
occur in the cooling environment, Other ruminants 3 4 8 3 7
via the transport trucks, or simply via Reptiles 0 8 13 4 1 3
dust and insects present in and
around the feed mills. However, Domestic solipeds 8 4 5 6 19 3
pelletised feed or heat-treated feed Other birds 7 4 3 2 4 1
is not available or used everywhere
as it is more expensive. Total isolations in animals 1568 1883 1280 1388 1594 1612
It often pays to have insight into
the audit-reports of your feed Table 1. Reported isolations of Salmonella enteritidis from animals in EU member states and other reporting
supplier. Water hygiene, especially countries, 2011-2016.
for the drinking water, is very
important as part of the biosecurity
program. Monitoring the drinking important to keep them out of your susceptible to an infection of the birds are kept in an environment
water quality is as important as poultry houses and hatcheries. The salmonella as it takes time before where there are no proper
purchasing safe feed. litter beetle is particularly known to the intestinal flora is fully biosecurity measures taken.
be a common host for salmonellas. developed. In general, the aim of
l People: Disinfection should therefore be vaccination for salmonella infections l Breeding:
Hatchery and farm workers are a key executed immediately after is the prevention or reduction of General health and disease
factor in an effective biosecurity depopulation of a house to prevent intestinal colonisation. resistance are key traits of Hendrix
program. It is of major importance the litter beetles from migration and This will lead to reduced faecal Genetics’ breeding programs. Via the
that they know and meet all the hiding. Besides cleaning and shedding, and as a result, less egg Feed4Food program, the company is
biosecurity standards and rules; it disinfection, it is important that you shell contamination. Besides, working together with universities,
pays off if you can fully explain the have measures installed to prevent diminished colonisation of the liver, feed companies and animal medicine
‘Why’? behind your biosecurity rodents and wild birds from entering the spleen and the reproductive companies on understanding more
program. your barns. Having bait stations tissues with salmonella is a result of about the birds’ gut health and
Make sure that they know and outside the poultry barns could be the induced response by the microbiota. This research will
respect the rules regarding the one of these measures. adaptive immune system, leading to hopefully lead to better insights in
shower-in procedures, the cleaning a reduced presence of salmonella in managing a flock in a healthy and
and disinfection of their hands after l Vaccination: eggs. sustainable way. With their intensive
every toilet visit and contact with There is an increased interest in It is known that S. enteritidis can health control programs (weekly
food. They must also follow the vaccinating poultry against S. persist in a vaccinated flock of laying monitoring of the health status of
rules with respect to changing enteritidis and S. typhimurium. With hens, but a vaccination program can the birds and their environment)
clothes and footwear between barns vaccination, the bird’s resistance to a be used as an additional tool to combined with all the measurements
as well as respect the rule of 72 possible infection of salmonella will lower the presence of S. enteritidis that they take to maintain their high
hours free of contact with domestic be further increased. The birds’ in eggs. level of biosecurity, they keep the
birds before entering the premises. natural resistance/first barrier In combination with the above- Hendrix Genetics’ breeding stock
against a possible salmonella mentioned strategies you can reduce salmonella free. n
l Pest control: infection is via their well-developed the chance of an infestation with
As all animals, including reptiles and intestinal flora. salmonella drastically. Vaccination References are available
insects, can carry salmonella, it is Young birds are therefore most against salmonella is useless when from the author on request
International Hatchery Practice • Volume 33 Number 4 9
10 International Hatchery Practice • Volume 33 Number 4
Ensuring the correct egg
setting to maximise
hatchery output
R ound end upwards – this is the way to
correctly position hatching eggs on
incubation trays. When eggs are
correctly set the embryo’s head is located
towards the air chamber in the blunt end.
Just before hatch, it uses the oxygen in the
air chamber to breathe.
by Miren Arbe, Vaccination Services
and Equipment Corporate Manager,
and Andras Medveczki, Veterinary
Services Manager, Hungary,
Ceva Sante Animale.
www.ceva.com
However, when the eggs are set upside
down, the embryo locates the head away
from the air chamber and it can not reach it Correct setting: The embryo’s head is Upside down egg: The embryo’s head is
to breathe. towards the air chamber in the blunt end. located away from the air chamber. The
The embryo will use the air chamber to embryo can not reach the air chamber to
breathe at hatch. breathe at hatch.
The impact of upside down eggs
at hatch
impact on hatchability. There was no chicks at hatch (Fig. 1). Both groups,
A field trial on a 40 week breeder flock was presence of blood during injection of correctly set into incubation trays, show
conducted to analyse the impact of egg properly set eggs. It must be remarked that approximately 3.5% of late embryo mortality
setting on hatchability and chick quality. when embryos are not properly positioned and cull and dead chicks despite in ovo
In the trial 1800 eggs were incubated – 900 at the time of in ovo (with the head under injection. However, the groups set upside
eggs were properly set before storage and the right wing and towards the air chamber), down before incubation show much higher
900 eggs were set upside down. At transfer there is an additional risk of poorly located late embryo mortality and a higher presence
time, half of each group was injected in ovo vaccine and, therefore, day old chick of cull and dead chicks at hatch; three times
and the other half was transferred without protection can not be ensured. higher in the non-injected upside down
any treatment. Results at hatch show that regardless of in group (11%), and five times higher in the
The first finding during in ovo was a high ovo treatment at transfer, correctly set eggs injected upside down group (15%).
presence of blood coming from the injected perform according to expectations because Regarding chick quality, the results from
upside down eggs. This is a consequence of there is no difference in the percentage of groups set upside down also showed a lower
accidental injections that might have an late embryo mortality and cull and dead Continued on page 12
Correctly set eggs injected. Fig. 1. Late embryo mortality and cull and dead chicks at hatch. Upside down eggs injected.
Correct egg setting Upside down eggs
16
14 n Cull and dead chicks
12 n Late embryo mortality
Mortality (%)
10
8
6
4
2
0
Non-injected In ovo Non-injected In ovo
International Hatchery Practice • Volume 33 Number 4 1110.0
Correct egg setting Upside down eggs
9.5
Pasgar score
9.14 9.17
9.0 9.00
8.89
8.5
8.0
Non-injected In ovo Non-injected In ovo
Visual quality of chicks Visual quality of chicks
hatched from correctly set hatched from eggs set upside
eggs. Fig. 2. Chick quality by Pasgar score. down.
Continued from page 11 level in the egg setting process. It has been average hatch of 83%, and €0.35 selling price
Pasgar Score (Fig. 2), as well as lower visual monitored that in manual operations, upside for day old chicks, the yearly cost of 0.5-
chick quality compared to chicks hatched down egg prevalence can reach up to 3% of 1.0% upside down mistakes can easily
from eggs that were set correctly. yearly egg production due to human error. represent more than €100K.
This fact will have an impact on the On the other hand, if eggs are set by a Innovative technology available on the
performance of the chicks later on. rolling system, up to 1% of the yearly market, such as the Ovosense Egg Setting
Therefore, it is concluded that upside down hatching egg production is expected upside Analyzer, identifies and marks the upside
egg setting into incubation trays has clear down due to round eggs. down eggs on arrival at the hatchery to
consequences on hatchability and chick relocate them in the right position before
quality. incubation.
Maximise hatchery output for Therefore, in a highly competitive market,
healthy day old chicks where antibiotic free production is a
Prevalence of upside down eggs constant pressure, the Ovosense Egg Setting
The annual cost of upside down mistakes on Analyzer maximises hatchery output by
The prevalence of upside down eggs in a the farm can be really high. For a hatchery giving fertile eggs a 100% chance to produce
hatchery will depend on the automation producing 60 million eggs per year with an a healthy day old chick. n
12 International Hatchery Practice • Volume 33 Number 4IB: minimising the impact
of variant strains on
breeder productivity
I nfectious bronchitis (IB) remains a
common and costly challenge for poultry
producers around the world, resulting in
widespread morbidity and variable mortality.
This highly infectious disease is caused by
Group 1 day
Vaccination
4 weeks 8 weeks
VN titer
14 weeks
1 Massachusetts 793B Inactivated IB vaccine 8.3
the IBV, a coronavirus which mainly affects
both the respiratory and urogenital tract. 2 Massachusetts Massachusetts Inactivated IB vaccine 6.9
Table 1. Average level of neutralising antibodies (2log) resulting from two different
by Dr Aris Malo, programs against IBV Q1, Variant 2, QX, Arkansas, Mass/M41 and 793B.
Boehringer Ingelheim,
Vetmedica GmbH, Germany.
www.boehringer-ingelheim.com different serotypes based largely on virus- levels of antibodies and therefore long-
neutralisation (VN) tests in several lasting immunity.
laboratory systems. IB isolates can also be In spite of the large number of variants
The most severe clinical signs are seen in identified molecularly (RT-PCR and RFLP test there are ways of improving the vaccination
chicks younger than six weeks of age. Signs or nucleotide sequencing). Different program in order to broaden protection.
of IB in affected birds include depression serotypes can co-circulate in the same area Broad protection can be provided against
and respiratory signs such as gasping, at the same time. Some are found most variants using existing live and
coughing and nasal discharge; when the worldwide, but others have a more inactivated IB vaccines.
kidneys are affected, birds may also have restricted geographical spread. Research demonstrates that a vaccination
increased water intake. Scouring and wet Extensive surveys reveal many different protocol, which features vaccines of more
litter are then common findings. The serotypes of IBV in different parts of the than one serotype, can provide broad
mortality rate will also increase. world. Among the known IB serotypes, the protection against a variety of strains. An
IB infections in layers and breeders can most important are the Massachusetts and example would be a vaccination protocol
result in drops in production and poor egg Arkansas serotypes in North America, that includes a live IB vaccine of the
quality; in these birds, infections during the Variant 2 in the Middle East and the Q1, QX Massachusetts serotype plus a live vaccine
first weeks of life can result in false layers, and 793B serotypes in Asia, Europe and other based on a different (variant) serotype.
which are birds that look and behave like parts of the world. Broadening protection in layers and
normal hens but are unable to lay eggs. breeders is essential to safeguard egg
production. This can be achieved by
Vaccination and broad protection administering heterologous live priming
IBV types followed by the use of the inactivated IB
Both live attenuated and inactivated (usually vaccine. This was evaluated in a study in
IBV has the ability to change rapidly in oil-adjuvanted) vaccines are used to control which the level of neutralising antibodies
nature and new serotypes may emerge as a IB infections. against different types of IBV was measured.
result of small changes in the amino acid It should be kept in mind that IBV strains Neutralising antibodies have the
sequence of the S1 gene of the virus spike. with different antigenic or genetic features characteristic of inhibiting or neutralising
This can result in new variant viruses. may still cross-protect in vivo, in the bird. any effect a virus may have biologically. The
Traditionally, IBV strains are classified into Such is the case for the Massachusetts higher the level of neutralising antibodies
serotype. Vaccines based on this serotype found in the blood of immunised birds, the
provide a fairly broad spectrum of higher the chance of blocking the virus and
Conjunctivitis and excessive tearing of the protection against other serotypes. preventing the damage that results from
eyes are symptoms of IB infection. Nevertheless, controlling IB is challenging infection.
because new strains of the virus continue to As shown in Table 1, a program featuring
emerge and the development of a new vaccination with live attenuated vaccines of
vaccine for every important pathogenic strain the Massachusetts and 793B types resulted
is unrealistic, time consuming and costly. in the highest average level of neutralising
Live attenuated vaccines are used both to antibodies against different strains (Q1,
protect young chickens and also to prime Variant 2, QX, Arkansas, Mass/M41 and 793B)
future layers and breeders prior to the included in the study. n
administration of an inactivated vaccine.
Vaccination usually starts in the hatchery,
by coarse spray. The use of an inactivated References are available
vaccine in layers and breeders leads to high from the author on request
International Hatchery Practice • Volume 33 Number 4 13weltech.co.uk
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14 International Hatchery Practice • Volume 33 Number 4Effective antibiotic-free
broiler breeder
production
A t the beginning of the last
century, the discovery of
antibiotics revolutionised
modern medicine. Humans found a
way to kill harmful bacteria and cure
Category
Probiotics
Product
• Competitive
exclusion
Distribution
Orally
Pros
• Gut health improvement
Cons
• Some are sensitive to water
quality
• Performance improvement
diseases responsible for thousands complete flora • No curative effect
• Reduction in pathogenic
of deaths. It was soon applied to • Live microbial bacteria colonisation Strain selection is key
food animals too. The growth of the supplement • Immunity boost
human population led to a
significant intensification of food • Can be associated with
prebiotics (i.e. synbiotics)
production, making the use of
antimicrobials more frequent in both Prebiotics • Non-starch Orally • Gut health improvement • No curative effect
animals and humans, not always in a polysaccharides • Performance improvement
sustainable manner.
• Immunity boost
• Can be associated with
by Dr Olivier Leon, probiotics (i.e. synbiotics)
Animal Health Director, Phytogenics • Essential oils, Orally/ • Measurable in vitro efficacy • Strong dependency on plant
Hubbard, France. plant extract Spray • Potential curative effect quality (affects the
www.hubbardbreeders.com concentration in active
substance)
• Selected part (leaves, stem,
Through time, infections once whole plant)
easily cured became more difficult
to treat, due to increasing antibiotic • Type of extraction
resistance (ABR). The mechanisms of Organic acids • Lactic, Orally • Measurable in vitro efficacy • Lack of consistency
ABR have been and still are the propionic, • Potential curative effect • Potentially buffered in the
subject of extensive research all over formic etc digestive tract
the world. In that scope, the ‘One
Health’ concept is being promoted Table 1. Short summary of alternatives for antibiotics (adapted from Gadde et al., 2017).
by international human and animal
health organisations.
Stakeholders, from regulation direct link to ABR as a risk in the on maintaining a proper hygiene at which is still under development for
bodies to industry operators, have human food chain), clonal transfer of farm level. about a week after hatching (notably
started taking major steps towards specific resistant bacterial clones Grandparent stock health, egg temperature regulation: accessible
the monitoring and reduction of through the broiler production management, hatchery hygiene and fresh feed and water, clean litter,
antibiotics usage. But more needs to pyramid has been described and control of the whole supply chain pre-heated house, temperature and
be done on a global scale: antibiotics shows the importance of ABR belong to the process as well. humidity control, light intensity, light
are still used in numerous countries control at all levels. It is not the purpose of this article uniformity and duration, ventilation
as growth promoters, a perfect Secondly, raising broiler breeders to describe all the steps taken and air flows are key factors in this
example of a short-term economic involves numerous technical before delivery to ensure maximum respect.
benefit with a long-term detrimental constraints which can unbalance the PS chick quality, but all these steps If the above mentioned
effect. bird’s homeostasis when not have a significant impact on the requirements are applicable to any
It is now widely accepted that performed appropriately. future breeder’s health and type of poultry, broiler breeders do
antibiotics should only be used This article looks at the main susceptibility to infection. have specific constraints which can
when animals are sick from bacteria, points to consider. Assuming the above steps have directly impact antibiotic use, as
which can be achieved with a change been fulfilled, and a fit and healthy illustrated by the two examples
of paradigm in the way broiler day-old PS chick is delivered to a below:
breeders (PS) are raised. Hygiene and husbandry thoroughly cleaned and disinfected l Ad libitum feeding of a
To achieve antibiotic-free good practice house, the importance of proper conventional broiler breeder will
production, the key prerequisite is to brooding conditions in this critical lead to very poor egg output (low
provide the most suitable The development of a disease in a phase cannot be emphasised peak, no persistence). Feed
environment to the birds. Gut bird is a result of the interaction enough. All suppliers have published restriction is therefore mandatory in
health, environmental conditions between a pathogen (specific extensive documentation on what order to keep growth on a
and the promotion of birds’ virulence or pathogenicity), the host ideal brooding conditions are for a controlled path leading to a
immunity are the pillars of the (immunity, age, genetic make-up) and specific cross or line, but they homogenous development of sexual
strategy. the environment. The ubiquitous should always be adapted to the maturity. Feed distribution becomes
Unlike broilers, the broiler breeder nature of bacteria and the structure local conditions. key for that purpose. When feed
case has its specificities: Firstly, even of poultry production make it easy Focus should be placed on distribution is not optimal, due to
though its economical purpose is to understand that a reduction in providing both quality and quantity lack of space, low distribution speed,
not meat production (hence a less antibiotic use does not only depend to day-old chicks, the physiology of Continued on page 16
International Hatchery Practice • Volume 33 Number 4 15Continued from page 15 performed in an accredited l When high antimicrobial vitro, it lacks consistency when used
inconsistent quantity or poor feed laboratory, where the tests resistance is observed. in vivo in field conditions.
structure, there will be sensitivity and specificity are up to l When the same pathogen is found Future alternatives include
consequences on gut health and standard and cross-contaminations flock after flock. bacteriophage therapy, which are
uniformity, opening the door to are controlled. Regular laboratory Last but not least, vaccine failure viruses targeting specific species,
superinfections by opportunistic tests with standardised samples should be thoroughly investigated, strains or serotypes of bacteria.
bacteria. should be regularly conducted to from delivery cold chain to vaccine Though the efficiency is widely
l Male management is another make sure there is no drift in the storage, preparation and vaccination documented, the spectrum is very
example. In case of artificial performance. procedure, including the way animals narrow, which is also why it is
insemination, untrained staff can l Staff training: are held during the process. extremely safe on the microbiota.
create injuries within the distal part Observance of biosecurity protocols Systematic blood sampling at
of the oviduct. In case of natural is now being studied and shows that around 20 weeks to measure
mating, mixing mature-enough males it is one of the main potential antibody titres is imperative to make Conclusion
to sexually receptive females is breaches. sure birds are thoroughly protected
required to avoid behaviour issues l Contingency plan: and that the rearing farm staff know An antibiotic-free strategy can only
leading to culls, scratches, over- Biosecurity breaches do occur. The how to perform the job correctly. be successful if good husbandry,
mating, lameness, cellulitis and so point is to be ready to deal with it, hygiene and biosecurity practices are
on. and be prepared: quarantined implemented by skilled staff.
It appears that skilled staff, able to shed(s), dedicated staff, arranging Staff awareness Alternatives exist, and many have a
identify abnormal behaviours or feed delivery orders, etc. preventive effect rather than a
environmental conditions, are a key Previously we have emphasised the curative one, reinforcing the
asset in the strategy to reduce importance of empowering the farm importance of providing a proper
antibiotic use. Mastering global Vaccination managers on the fundamental environment.
hygiene and proper breeding physiological and technical At the broiler breeder level, the
conditions better controls Ensuring birds’ optimal immunity is requirements of broiler breeders. task is complicated by the inherent
opportunistic superinfections. one of the keys to avoid the use of A key parameter, called observance, stress imposed on the bird due to
antibiotics. Let’s not forget that describes the probability of the specific physiological and technical
viruses, on top of their own actual implementation of rules and constraints: feed restriction, male to
Biosecurity virulence, can serve as a door opener procedures. female behaviour and lifespan to
for opportunistic bacteria: avian The drivers to obtain observance name a few.
Biosecurity encompasses the steps metapneumovirus is an infamous have been studied mostly in the The misuse of antibiotics can lead
taken in order to prevent a pathogen example. marketing or medical field, but also to the development of resistant
from entering the shed, from going Vaccines will not usually prevent in poultry biosecurity. Observance bacteria impairing the success of sick
out of a shed or from spreading to infections, but will dramatically depends on education, experience, poultry treatments. On a larger scale,
nearby sheds. It proceeds from a reduce the clinical consequences, motivation and personality traits. antibiotic resistance is now
thorough analysis of the flows in and and generally reduce shedding. Modern poultry companies have to considered as one of the major
out of the farm, in order to identify Vaccination against salmonella has invest in improving communication threats to human health. The trend is
the potential sources of been a key pillar of salmonella and training, in order to make sure inevitable: the poultry industry and
contamination and implement the control in some European countries procedures are properly applied. the whole food animal industry in
cheapest most efficient control for example. general have to find ways to reduce
procedure. The development of autogenous and better use antibiotics.
Potential sources include people, vaccines has been a significant help Alternatives to antibiotics The global demand for ‘free of’
pests (rodents and mites), in the management of specific markets is on the rise, and pushes
equipment, transportation, feed, pathogens. They consist of the Many well-written reviews can be the industry to adapt. Several
water, litter and surrounding development of a custom-made found to list products that partially countries have identified an
environment. Because it is adapted inactivated vaccine containing the or totally mimic that of antibiotics. increased risk in imported broilers or
to each specific context, there is specific strain or multiple strains of Table 1 is a non-exhaustive list of broiler meat compared to locally
unfortunately no copy and paste pathogens. There are different available alternatives. The majority produced products.
miracle recipe. There are however contexts in which autogenous of them are distributed orally, which It is only with an integrated
three areas which should not be vaccines can prove very useful: emphasises the importance of gut approach involving all stakeholders
overlooked: l For bacteria against which cross- health management for the success and policy makers that a reasonable
l Laboratory reliability: immunity between different strains of an antibiotic-free strategy. objective can be set in order to
To ensure the biosecurity plan is (different serotypes for instance) is Phytogenic products can also be tackle the threat globally. n
efficient, a regular monitoring of not protective enough, like E. coli. administered by spray, to specifically
significant contaminants is needed l When commercial vaccines show target respiratory stress. There is a
(salmonella, mycoplasma, influenza, inconsistent results or are not certain unanimity to admit that even References are available
etc). This crucial step has to be available. though efficiency has been proven in from the author on request
16 International Hatchery Practice • Volume 33 Number 4breeder nests
Unique design offers smart
solution for breeder nests
The new Agromax Smart Manual contamination. The egg belt, made
Nest (ASMN) shares most of the from plastic, is easy to clean and the
advantages of an automatic roll away perforations keeps the eggs apart
community nest due to its unique and prevents them from cracking or
design. breaking.
The Agromax Smart Manual Nest is
agromax.nl made especially for markets where
labour costs are low.
Advantages include:
l Maximum production of high
quality hatching eggs.
l Minimum cracks and hair cracks.
l Minimum floor eggs.
l No need for nest bedding
material which can bring
infection with it.
Excellent technical results provided
The eggs are collected
from a central egg belt, which is a
by high quality laying nests
short distance, resulting in quick
cooling of the eggs and reduced For the poultry industry, Van Gent them off at the end of the day. This
laying nests and slats (hardwood and prevents broody hens and soiled
plastic) are known for their high nests, and the benefit is clean eggs.
quality and durability. With the unique two part expulsion
Enhanced welfare with unique The products are fully designed in
order to balance efficiency of use,
fence, the entire nest surface can be
used, which results in a familiar and
shape of automatic nest system while promoting the natural
behaviour of the birds.
comfortable place to lay eggs.
l Open Astro-Turf mat ensures that
This approach is visibly rewarded the nests stay free of dust and
The Tavsan Comfort + automatic Thanks to the specific design the in the excellent production results droppings.
nest has a unique shape that is breeders cannot reach the eggs after achieved. l Two separate egg belts of 25cm
completely different from they are laid so damage to the eggs makes the roll distance as short as
conventional automatic nests on the is avoided. vangentnl.com possible and limits cracked shells to
market. Advantages include: a minimum. The nests are available
l Nest with high air volume (0.42m³ The structure of the laying nests is with woven or perforated egg belts.
tavsan.com per cell). simple. They are stable as well as l The roof of the laying nest is
l Slat heights can be manufactured easy to clean and, because of the partly hinged for nest inspection.
Due to the specially constructed in 300, 350, and 400mm according to design, they have an easy and Another portion of the roof can be
design there is far more air volume customer preference. modular assembly system. lifted off for inspection of the egg
and a wider area that greatly l Up to 50% labour saving. Features of the Van Gent Standard belt.
contributes to bird welfare during l Improved hygiene. nest include: l The egg belt cover prevents
egg laying. l Number of cracked eggs are kept l Film faced plywood ensures easy draughts in the laying nest as well as
The Tavsan Comfort + is almost at a minimum level. cleaning and guarantees a long dust soiling the belt and eggs.
completely made of plastic l Specially selected shape and lifespan. Van Gent automatic roll away
materials, which is the other colour for less floor eggs. l The nest is characterised as user- laying nests are a successful concept
important difference from existing l High litter quality. friendly and easy and quick to from a company with over 45 years
automatic nests on the market. This l Eggs can be collected any time assemble. of practical experience. The nests
all virgin plastic structure makes during the day. l The expulsion system removes are available in different
Tavsan Comfort + far more durable l The expel system prevents the the hens from the nests and closes configurations.
in the long term, prevents bacterial birds sleeping in the nest during the
growth forming on the integral side night. This offers more clean eggs.
walls and adds flexibility and l The nest top is hinged so that the
strength to the body. user can open and check inside the
nest at any time.
International Hatchery Practice • Volume 33 Number 4 17Group and single-hole nest systems
for breeders
For those desiring a group nesting provides a sturdy, quiet environment
solution, Chore-Time offers its for birds that is easier to clean and
Valego nest system for breeders, more bacteria resistant than a plastic
which features a sturdy, quiet, clean or steel construction. Its ability to
and spacious environment in which quickly dissipate moisture also
breeders thrive. makes it an ideal material for use in
nest systems.
choretime.com For those who prefer an individual-
hole nest, Chore-Time also offers its
Valego nests include Chore-Time’s side- and centre-belt nests. The
patented Rack-Drive Expulsion (RDE) nests are available with two nest
E AY system for superior egg protection, hole widths, 24 or 30cm, providing
IB helping a higher percentage of eggs flexibility in matching the hole size
R D
BS TO
C reach the egg belt safely versus to the bird size for increased bird
U floor-lift systems. comfort.
S E
LIN With the Valego System, Chore-
Time’s egg belts, expeller and
Chore-Time’s side- and centre-belt
nests feature hinged galvanised nest
ON controls comprise a total egg
collection system that ensures a safe
lids to help with training hens not to
roost in the nests. An automated lid-
trip for the egg from the hen to the closing kit permits scheduled
collection table. A control unit operation of the nest lids for cleaner
programs the daily opening and nest bottoms and cleaner eggs.
closing of the expeller to optimise Nest lids can be winched manually
the period when hens have access to or using a whole-house control such
the nests. as Chore-Time’s Chore-Tronics 3
The control also initiates slight controller.
movement of the expeller during A natural step-up slat is
egg collection, which permits birds incorporated on the side- and
to stay in the nests, while helping to centre-belt nests’ egg tray cover to
prevent accidental bird damage to ease entry to the nest. Side-belt
the eggs. nests also include hinged egg tray
The RDE system is strong enough covers for easy access to the egg
The targeted publication for to eject any dead birds. It
significantly reduces labour needs,
belt when needed. Collection tables
are available for both side- and
professionals seeking the which helps to reduce production
costs, while also minimising the
centre-belt models.
When used with Chore-Time’s
latest global technical burden of finding employees in
tough labour environments.
innovative feeding, drinking and
climate control systems, Chore-
information The walls and roofs of Valego
nests are made with durable, A-
Time’s group and individual-hole
nesting systems provide an ideal
grade, film-faced plywood, which solution for breeder production.
To feature
For more details please contact
your products
sw@positiveaction.co.uk
www.positiveaction.co.uk Contact: +44 1377 241724
18 International Hatchery Practice • Volume 33 Number 4breeder nests
The perfect group laying nest
for broiler breeders
Big Dutchman’s group laying nest l Clever, wood-free nest design for
Relax was developed specifically for optimal hygiene and cleaning.
broiler breeders. It helps maintain a l Use of high-quality materials,
high hygienic standard. The eggs’ perforated nest insert made of
roll-off distance from the nest to plastic.
the longitudinal egg belt is very l Easy to clean with minimal labour
short. requirements.
l Simple and almost screw-less
bigdutchman.de plug-in design for quick and easy
assembly.
Another feature is the automatic l Solid nest legs made of plastic.
and reliable nest-closing system for No danger of corrosion.
the night that keeps hens from l Manure pit with plastic slats for
sleeping and brooding inside the
nest – and therefore from soiling it.
healthy feet, good manure
penetration, and thorough cleaning.
Winchable nest system for broiler
The divided roof with anti-roost
rocker permits optimal monitoring
To improve hygiene inside the
house, part of the house should be
breeder housing
of the nest and the egg belt. The used as a manure pit and equipped
special nest insert made of plastic with slats made of plastic. These A hen has the natural desire to The Grando Condor suits both
has a comfortable surface easily plastic slats, specially developed by breed. To enhance her chance for natural and tunnel ventilated houses.
accepted by the hens. Big Dutchman, have the following offspring she will look for a safe, The layout is comparable to a layout
With the Relax nest, Big Dutchman advantages: clean and sheltered place to lay her for manual nest boxes. It exists of
provides ideal conditions for a high l Comfortable and soft for the eggs. She will demonstrate this same two rows of nest-blocks and
share of hatching eggs, and thus for birds and the secure foothold behaviour in a breeder house. walkovers. The change from manual
successful broiler breeder facilitates fertilisation. to automatic egg collecting system
production. l No sharp edges or corners so no vencomaticgroup.com will be a small change in
Advantages of the Relax nest danger of injury and chest bruises. management.
include: l Very small surface, similar to wire For successful hatching egg The winchable nesting system
l Excellent hatching egg quality, low flooring for optimum manure production it is therefore essential facilitates bird training and cleaning
percentage of cracked and hair- penetration; the slats stay clean to create the conditions that allow of the house and nesting system in
cracked eggs. throughout the batch. this behaviour. A comfortable and between rounds. All these features
clean nest that fits the natural result in better economic
behaviour of a hen is essential. performances and lower operational
Vencomatic Group has launched a costs.
new nest type for broiler breeders, All Vencomatic nests are equipped
the Grando Condor. The Grando with a unique tipping floor. The
Condor is the winchable nest system tipping floor mechanism pushes out
for broiler breeder housing. This nest the birds to prevent broodiness and
is especially developed for hot, soiling of the nest. It also makes dust
severe climate conditions. Its strong and dirt fall down leaving a clean
solid construction and choice of nesting area. The tipping floor, in
materials together with the unique combination with the special
features of a Vencomatic nest ensure Vencomat flooring, provides security
optimal hatching egg quality. for perfect egg quality.
HATCHING EGG WASHERS
l Low nest entrance height. High l No contact surface between the
nest acceptance, fewer eggs on the slats for prevention of hotbeds for HATCHER TRAY WASHERS
floor. mites and other vermin.
l Nest depth of 47cm. Short rolling- l Quick and easy assembly. COUNTERS-SEPARATORS-UNSTACKERS
off distance and gentle egg Another great new feature is the
transport. nest-integrated bird scale Nesca.
l Egg channel available in two When the hens visit the nest to lay
widths: 400 or 500mm or with their eggs, their weight is now
divided egg belt (2 x 200mm). determined during this visit.
l Automatic and reliable nest- Whether the hens are heavy, light
closing system for the night. High or lazy, Nesca measures the weight
functional reliability, low of nearly all females. KUHL CORP.
maintenance requirements. Without any additional effort,
l Divided and very light nest roof farmers can thus record a very large FLEMINGTON, NJ 08822 – USA
for optimal monitoring of nest and weight range of the birds in their www.kuhlcorp.com hyk@kuhlcorp.com
egg belt. flock.
International Hatchery Practice • Volume 33 Number 4 19Co-hosted by Positive Action Publications Ltd and VNU Exhibitions Asia Pacific
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www.positiveaction.info/ppdfa2020
www.vnuexhibitionsap.com4. Using the right breed for the right market
by Paul Kelly, Kelly Turkeys. www.kellybronze.co.uk
W hat is currently happening in the turkey breeder world? As in all
livestock sectors the advances in turkey breeding over the past
50 years has been phenomenal. The industry has done a
spectacular job in producing affordable quality meat in the most efficient
way possible. The continuous increase in growth rates year on year brings
with it some challenges for some of the various sectors of the turkey
market.
The international turkey breeders l Stage 3:
are, of course, breeding for the Skeletal growth.
mainstream world market, which is
for deboning into turkey primal cuts l Stage 4:
for further processing. Muscle development.
There are though various markets
in the world that require whole birds l Stage 5: Fig. 2. Many turkeys are killed when
and crowns and saddles for seasonal Laying down of fat. they are simply the right weight and
markets. In world terms they are not when they are ready to eat!
niche, but of course important for As the commercial turkey has been
the countries that have these whole bred for processing and meat
bird markets. stripping at heavy weights the result quality carcase weights at under 6kg
These whole carcase markets is a bird that reaches popular whole then a smaller slower growing breed
require a breed that produces a carcase weights at a very young age. is needed to supply a good quality
quality carcase at popular table Currently in most markets the carcase. The pictures in Fig. 1 show
weights. Popular eviscerated carcase females from standard large breeds the differences.
weights for the whole bird fresh are used to produce whole carcase The turkey industry needs to
market are 3.5-6.0kg. and bone-in crowns and saddles. accept that in order to keep and
The whole carcase requires The females take between 9-11 maintain the whole carcase market
different selection pressures and weeks to get to these popular then it must not supply a product
parameters to those for the further weights; the male just 7-10 weeks. that is not fit for purpose. Many
processing market. In my opinion killing turkeys at this turkeys are killed when they are
To understand why different age produces a product that is simply the right weight and not
breeds are needed for the whole simply not good enough and gives when they are ready to eat! smaller breeds supplies, in most
carcase market a simple lesson in turkey a bad reputation for eating The pictures in Fig. 2 highlight cases, the perfect weight profile and
physiology is needed. quality. The turkey is still in stage these differences. therefore does not lead to the waste
There are five main stages of three of development and is just a and perceived welfare issue of
development in all species: bag of bones. destroying surplus off sex.
The large breeds were dual NOTES
l Stage 1: purpose in many ways in that the l The costs of production are
Development of blood supply and male was perfect for further l To supply these whole bird slightly higher but the reduction in
nervous system. processing and the female was markets in the volumes needed in downgrades in the factory (broken
perfect for the whole carcase the seasonal peak weeks requires wings are not an issue) and the lower
l Stage 2: market. more females than males. So more mortality of the smaller breeds more
Development of vital organs. This has changed and to produce eggs are set to supply the females than compensates for the slight
and the males are, in many cases, increase in live weight costs.
surplus to requirements so therefore
Fig. 1. To produce good quality carcase weights at under 6kg, then a smaller destroyed. l Using the smaller breeds gives a
slower growing breed is needed. much larger meat to bone ratio. Fig. 3
l An as-hatched program using shows 50% more breast meat. n
Fig. 3. Using the smaller breeds gives a much larger meat to bone ratio.
International Hatchery Practice • Volume 33 Number 4 2122 International Hatchery Practice • Volume 33 Number 4
Providing the ideal
environment to maximise
laying potential
T he industry has seen a large
increase in the construction of
modern environmentally
controlled houses across regions
where open sided housing was the
With ever increasing numbers of
broiler breeders being placed in
regions of the world with high
summer temperatures, the approach
to providing the ideal environment
norm, especially in the tropical to maximise production should be
regions of the world. One of the focused on the nesting, house
primary reasons for these changes in structure and environmental control
housing is the need for higher levels systems.
of biosecurity, especially in countries
with high concentrations of both
commercial and domestic poultry Improving labour utilisation
and ongoing outbreaks of diseases
such as avian influenza. The adoption of mechanical
community nest systems across the
industry is being driven by the need
by Andrew Bourne to improve labour utilisation and
Cobb, USA. biosecurity, which in turn has led to
www.cobb-vantress.com increases in stocking densities from
4.5 to 5.0-6.5 hens/m².
Higher stocking densities means Minimise the height difference between the ceiling and the slat scratch
The drive for ever higher levels of higher house heat loads and pressure areas. The lower the difference the better the airspeed distribution. The
efficiency and rising labour costs, has on ventilation systems to maintain lower the pitch on the roof or drop ceiling the better.
seen the broiler breeder housing and hen comfort and welfare. These
equipment industry continue to higher stocking densities require
develop, introducing modern more efficient ventilation systems in The assumption still prevails that in a most important aspect of any new
technologies in line with trends in both the hot and cold seasons. hot climate insulation is not broiler breeder house and insulation
modern management, commun- Furthermore, the mechanical important and the benefits do not choice is critical to optimise bird
ication and ventilation systems. nesting and feeding systems have outweigh the high cost. comfort and welfare.
As expected with these unique ventilation requirements due The vast majority of tunnel
developments, early adoption has to their influence on air movement l Lack of perimeter inlets for ventilated broiler breeder houses in
been in markets such as Europe and dynamics. minimum and transition ventilation. most tropical or sub-tropical regions
North America, with their Many new investment decisions of the world will have a non-
historically high labour and utility are often made without taking into l Inadequate static pressure insulated drop ceiling, constructed
costs, which easily justified full consideration the high levels of controls due to poor sealing of of sheet metal or plastic.
investment in and adoption of these environment control needed to houses – often through poor While this design helps to reduce
modern technologies. ensure optimum bird performance. roof/ceiling and curtain installations. solar heat penetration and affords
Due to the market volatility Some common mistakes, especially small amounts in terms of insulation
experienced by most poultry in tropical countries to reduce value compared to an uninsulated
growers in many of the developing investment costs, include: Total heat load open truss metal roof, the
countries financial constraints advantages of insulation cannot be
continue to limit access to improved l Poor or no insulation in either the The total heat load in any broiler understated.
equipment and housing designs. roof or on top of the drop ceiling. breeder house is a function of how The thermal image in Fig. 1 is of a
much heat is transferred to the house under construction with a
house through the building surfaces, plastic drop ceiling installed below
Fig. 1. Thermal image of a house under construction. the heat entering via the ventilation the metal roof with some insulation
system and most importantly the material already in place. The
amount of metabolic heat produced thermal image spot temperatures Sp1
Measurements by the birds. and Sp2 are intended to illustrate
Heat flows through surfaces from the value in terms of surface
Sp1 30.5˚C hot to cold, entering the house temperature reduction of the
through the ceiling, side walls and insulated versus non-insulated
curtains. The higher the resistance to surfaces: Sp1 (no insulation) 30.5°C
Sp2 26.6˚C flow or higher the R value of the compared to Sp2 26.6°C.
surface, the lower the emissivity. As These lower surface temperatures
Sp3 25.6˚C well as entering the house through indicate significantly improved
all surfaces, heat is also produced by insulation or heat transfer. During
the birds which is by far the greatest hot days this differential will be even
Sp4 27.4˚C contributors to heat load in a well- more extreme.
designed and insulated tunnel house. A broiler breeder house in a hot
The roof is probably the single Continued on page 24
International Hatchery Practice • Volume 33 Number 4 23You can also read
