Optimizing production from floor-housed pullets and hens
The use of perches can increase the use of vertical space, help birds learn to jump and climb and assist in developing their leg and flight muscles.
Neil O’Sullivan, PhD
4 • Industry Egg • August 2009 • www.WATTpoultry.com
Hy-Line selection programs, in common with most primary breeders, involve coordinated evaluation of strains on
research farms in a molecular biology laboratory, an egg quality laboratory and ;eld
progeny tests. The objective of our genetics
program is to achieve continuous improvement in all traits. Genetic progress must be
measured annually applying a variety of
techniques. These include ;eld tests of sire-coded crossbred daughters held under commercial conditions in multiple bird cages
within representative areas of the U.S. and
other countries. Both ;eld production data
and egg quality assays are used in evaluation. Research farms evaluate pedigree pure
line daughters under strictly controlled conditions on one location in single bird cages.
Performance and quality are evaluated and
are subjected to computer analysis to develop Breeding Value Estimates.
Consistent with commercial demands,
we and other primary breeders are aware of
the importance of behavior as it impacts livability and production. Hy-Line is constantly
striving to produce commercial strains which
are compatible with emerging demands for
sustainability. This implies improved feed
conversion ef;ciency and a low volume of
solid and liquid waste from ;ocks. Pullets
and hens must now be adaptable to ;oor production systems in addition to cages. This
has implications for the inherent drive for
dominance, the use of nest systems and retention of feather cover.
Behavioral issues in floor flocks
Signi;cant problems encountered in ;oor
systems include:
✔Fear - External stimuli and inter-;ock
interaction results in secretion of stress hormones which detract from optimal production by initiation of behaviors which impact
feed and water intake and the use of nests
and perches.
✔Elevated mortality – This may be due
to trauma such as vent peck or chronic stress
which may depress the immune response and
render ;ocks susceptible to infections which
would otherwise elicit an antibody response.
✔Broody behavior – A transitory cessation in egg production, associated with the
secretion of prolactin. Affected hens sit in
nests or on ;oor nests and are recognized by
;uffed plumage and characteristic vocalization. The problem is generally initiated by
overcrowding especially with high ambient
temperatures.
Reducing stress for flocks
The key to preventing many behavioral
issues lies in appropriate housing and management and achieving socialization within
;ocks. It is an unfortunate consequence of
generally lower mortality attributable to improved breeding, vaccination and housing,
that many ;ocks have insuf;cient contact
with humans. Wider use of controlled environment systems also limits contact with
caretakers. Young ;ocks are frequently not
habituated to stress factors associated with
climatic change, noise, and exposure to unfamiliar equipment, and placement of feed and
water lines at the time of transfer from pullet
rearing to laying units.
House design should incorporate full light
control which allows bright illumination during the brooding period and when ;ocks are
inspected at intervals during the day. Low
Use of Perches (Adult Birds)
Bird Density
ft2/hen
Length of Perch
Space in/hen
1.0 3. 2
1. 2 2. 2
1.4 0.8
Perches should be placed on slats where
possible to maintain good litter conditions.
levels of light should be selected during the
mid to late growing period.
Partial litter houses allow pullets to peck
which is a natural behavior. Rearing pullets
on stretch wire or slats will result in displacement pecking which can take the form
of feather pecking of the neck at the time of
maturity.
Perches are essential to develop the mus-
