©2014 Poultry Science Association, Inc.
The development of injurious pecking
in a commercial turkey facility
G. Duggan,* T. Widowski,* M. Quinton,* and S. Torrey*†1
*Campbell Centre for the Study of Animal Welfare, Department of Animal
and Poultry Science, University of Guelph, Guelph, ON N1G 2W1, Canada;
and †Agriculture and Agri-Food Canada, Guelph, ON N1G 2W1, Canada
Primary Audience: Turkey Producers, Researchers, Poultry Veterinarians
SUMMARY
Injurious pecking is considered a major economic concern and affects all sectors of commercial poultry production. Though extensive research has been performed examining feather
pecking in layer chickens, little information exists regarding feather or head pecking behavior
in domestic turkey flocks, and less still in commercial settings. The objective of the present
field study was to examine the development of injurious feather and head pecking in tom turkeys raised in 2 different commercial environments. At a commercial facility, 49,332 beak-conditioned tom turkeys were placed in 8 barns (5,000–7,500 turkeys/barn) and studied through 16
wk of age. Approximately half were housed in control barns in March 2010; these barns were
environmentally controlled (artificial light and tunnel ventilation) in both rearing and growing,
with a density of 0.16 m2/bird for rearing through 4.5 wk and 0.39 m2/bird for growing through
16 wk. The remaining turkeys were housed in curtain-sided barns in April 2010; the 4 rearing
barns were environmentally controlled with a density of 0.10 m2/bird, whereas the 4 growing
barns had natural light and ventilation and a density of 0.36 to 0.38 m2/bird through 16 wk. Two
barns from each growing environment were provided with multicolored plastic balls as enrichment. Each housing and enrichment combination had 2 replicate barns. Behavior, weights, and
feather condition were assessed every 3 wk. Mortalities and culls were recorded as they occurred. Turkeys in curtain-sided barns had worse feather condition and more culls and mortalities with severe pecking injuries compared with those in control barns. In both environments,
severe and gentle pecking was observed throughout production, and the majority of culls and
mortalities had severe pecking injuries. More controlled studies are needed to parse the causal
factors of injurious pecking in toms.
Key words: turkey, injurious pecking, environment, mortality, enrichment
2014 J. Appl. Poult. Res. 23:280–290
http://dx.doi.org/10.3382/japr.2013-00860
DESCRIPTION OF PROBLEM
Injurious pecking is a problematic behavior
that has developed in most commercial poultry
production facilities [1] and raises both econom1
Corresponding author: [email protected]
ic and welfare concerns. This behavior is considered an inappropriate pecking activity directed
toward conspecifics [2] and involves repeated
pecking at the feathers or head of a victimized
bird, leading to the removal of feathers or skin
Duggan et al.: INJURIOUS PECKING IN TURKEYS
[3]. This is an important issue economically, as
denuded birds experience increased heat loss
and require additional feed intake to maintain
thermoregulation [4]. Production efficiency can
be dramatically reduced, especially if high rates
of pecking and feather loss occur in a flock. Furthermore, injurious pecking often leads to cannibalism, a behavior that is capable of spreading quickly through entire flocks, resulting in
culling and mortality [2]. In chickens, numerous
causes of severe injury-causing feather pecking
have been discussed at length [5, 6]. However,
little research has been conducted toward injurious pecking in the domestic turkey [7], and even
less as it occurs in commercial flocks. Pecking
injuries may be the leading reason for the majority of culling in mature turkey flocks [8] and this
adverse behavior must be investigated further to
improve welfare and curb production losses.
In North America, turkeys are commonly
raised in either fully enclosed or curtain-sided
barns. Enclosed environments separate the birds
from external climates and allow for greater
control of internal environmental conditions,
whereas curtain-sided barns provide the growing birds with greater exposure to outdoor conditions and natural sunlight. In numerous studies, researchers have examined how different
environmental parameters can affect aggressive,
severe pecking behavior in chickens and turkeys
[9–12], and these 2 environment types used in
North America may play a significant role in the
development and persistence of injurious pecking in a commercial turkey flock. In addition
to growing environment, various enrichments
may help direct pecking behavior away from
conspecifics and toward an alternate target [3,
13, 14]. However, the efficacy of an enrichment
to reduce pecking in a commercial turkey flock
had not been previously examined. Therefore,
the objective of this field study was to examine
the development of injurious pecking in commercially housed domestic turkey flocks in 2
common housing environments. Additionally,
the effectiveness of an occupational enrichment
device was evaluated in an attempt to mitigate
this problematic behavior at the production level. We hypothesized that pecking rates would be
higher in the curtain-sided barns, but lower with
enrichment.
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MATERIALS AND METHODS
Ethical Note
The use of all animals involved in this study
was approved by the University of Guelph Animal Care Committee and adheres to the guidelines of the Canadian Council on Animal Care
[15]. Any required euthanasia was conducted
and recorded by farm management during daily
farm maintenance.
Birds and Experimental Design
In the current field study, we examined 2
factors (housing and enrichment) in 8 barns in
one production facility in southwestern Ontario.
Each combination had 2 replicate barns. In the
spring of 2010, 49,532 one-day-old White Hybrid [16] male tom turkey poults were placed
in one production facility under the same management protocols. All poults were beak conditioned at the hatchery before placement. The
first cohort of 19,332 poults was placed in March
2010 and the second cohort of 30,200 poults was
placed in April 2010. Poults from both cohorts
were sourced from the same hatchery. Each cohort was divided into 4 equal groups and placed
into poult-rearing barns. The first cohort was
housed in 4 poult barns, each measuring 780.39
m2 in area (0.16 m2/bird). The second cohort
was housed in 4 poult barns measuring 754.84
m2 (0.10 m2/bird). Wood shavings were provided as litter. Water was available through nipple
drinkers and standard starter feed was provided
ad libitum. Birds were reared in the poult barns
until 4.5 wk of age, when they were transferred
to an adjacent grower barn and raised to a market weight of approximately 14 to 16 kg.
The first cohort of birds was transferred to the
enclosed, 2-story grower barns (4,832 in 3 barns,
4,836 in 1 barn). These barns were entirely enclosed and termed the controlled barns. Minimal
natural light entered these barns, and the majority of illumination was provided by fluorescent
tube bulbs. The controlled barns were 2-storied
and each measured 19.20 × 97.54 m, providing
the birds with a total area of 1,872.93 m2 and a
space allowance of 0.39 m2/bird.
The second cohort was moved from the poult
barns into the second grower environment,
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282
termed the curtain-sided barns. These barns
were single-storied, housed 7,500 (2 barns) or
7,600 (2 barns) turkeys and measured 19.8 ×
139.29 m, creating a space of 2,757.9 m2 with
a density of 0.36 to 0.38 m2/bird (depending on
population of barn).
Across all barns, water and grower feed were
provided ad libitum and straw litter was provided. Turkeys were fed a commercial ration in pellet form that met or exceeded nutrient requirements. Litter remained unchanged for the entire
grow-out period, with the exception of 1 curtainsided barn where half the litter was replaced due
to flooding of the barn during wk 2.
For the entire rearing and growing periods,
supplemental lighting regimens remained identical for both the controlled and curtain-sided
barns. The birds were provided a full 24 h of
light during the first day of placement, supplied
by 91.44-cm long fluorescent tube lighting [17].
From 1 to 5 d of age, each rearing barn had a 1-h
dark period during the night (0000–0100 h). At
5 to 10 d of age, the photoperiod was 22L:2D,
with the dark periods from 0000 to 0100 and
0300 to 0400 h. At 10 d of age, the photoperiod
was changed to 18L:6D, with two 3-h dark intervals during the night. This lighting schedule
was maintained for the remaining duration of
the experiment.
Light levels were measured periodically in
each housing environment. Readings were taken
in each barn on every sampling day at 12 points
from the barn perimeter and center using a handheld light meter [18]. Readings were taken at
approximately 12 cm from ground level. Within
the controlled barns, light intensity averaged
32.5 ± 3.8 lx (range: 1–145 lx). In the curtainsided barns, light intensity averaged 861.6 ±
74.5 lx (range: 150–4,800 lx).
Enrichment
Enrichment was placed in 4 of the 8 barns,
creating 2 enriched and 2 not enriched barns for
both the controlled and curtain-sided barns. The
enrichment was provided in the form of colored
(equal distribution of yellow, red, green, and
blue) plastic balls measuring 7.62 cm in diameter [19]. Five hundred hard plastic balls were
placed in each of the enriched barns, generating
a density of 9.7 birds per ball in the controlled
barns and 15 to 15.2 birds per ball in the curtainsided barns. For the enriched groups, balls were
spread throughout the grower barns before the
turkeys were transferred. Apart from the addition of this enrichment, all regular barn conditions and management procedures remained
identical to regular production conditions across
all barns.
Data Collection
Feather Scoring, Weights, and Mortality.
Average feather scores and weights from 100
randomly sampled birds in each barn were recorded at 6, 9, 12, and 15 wk of age. On each
sample day, in 4 different areas throughout the
barn, groups of approximately 25 birds were corralled using plastic-coated chicken wire (7.62 m
in length), one group at a time, to provide a block
against repeatedly sampling birds while increasing the variability of samples. While corralled,
each bird was gently handled and weighed using digital scales [20] and their feather condition
was scored according to a laying hen-scoring
method [21]. This scoring method involved the
inspection of 4 body regions (neck, back, wings,
and tail) with each region receiving a score from
1 (very poor feather coverage with skin damage)
to 4 (very good; no feather damage). Intermediate scores were given for partially nude areas,
where little (score = 2) to no skin damage (score
= 3) was present. Scoring was conducted by a
single researcher throughout the data collection
period. The maximum total score was 16, and
a higher score denoted better feather coverage.
In addition to regular data collection, farm management maintained records of all dead or culled
birds with daily data sheets. These records also
specified whether culled or dead birds had severe pecking injuries.
Behavior. Pecking behavior in each barn was
recorded from observations made with the use
of video recordings in each barn at 6, 9, 12, and
15 wk. Behavioral recording days occurred 2 d
before or after feather scoring and weight data
collection. During each sampling day, a video
camera [22] was set up in each barn to record
1.5 h of regular activity and behavior between
1000 and 1500 h. The cameras were positioned
to record approximately 41 m2 of viewable barn
area, with numerous water and feeder lines vis-
Duggan et al.: INJURIOUS PECKING IN TURKEYS
ible. The positions of the cameras were randomly selected each sampling day to achieve greater
variability in observations and were placed at
approximately 2.13 m in height.
Data collected from video recordings were
analyzed by 2 trained observers (kappa statistic
for interobserver reliability = 0.87). Using focal
animal sampling, the occurrence of 3 mutually
exclusive behavior patterns was recorded: object
pecking (pecking directed toward environmental objects or enrichments), gentle pecking (investigatory pecking that did not elicit a reaction
by the recipient), and severe pecking (vigorous
pecking that elicited a reaction by the recipient
or involved removal of feathers or integument).
Video observations began 10 min into each
recording, allowing the birds to acclimatize to
the presence of the camera. Six 5-min observation periods occurred at 10-min intervals per day
per barn. The area of the barn seen on each video
was divided into 5 zones of approximately equal
area using feeder and water lines as reference
points. From each zone, 2 focal birds were selected at random from the visible birds, and each
was observed for 30 s for all occurrences of behavior. All behavior was recorded in sequence.
This method was adapted from Lambton et al.
[12] and effectively allowed 2 birds to be sampled from each of the 5 zones within each 5-min
observation period. Altogether, the behavior of
60 birds was observed from each video recording. During the observation period, if a focal
animal became blocked from view or left the
designated zone, another bird was selected and
observed for the remainder of the 30-s observation period.
Statistical Analysis
Statistical analyses were performed with SAS
[23] using a GLM with repeated measures. Data
from the experiment were analyzed as a completely randomized design with the 2 main factors (barn environment and enrichment) in a factorial arrangement and 2 replicates per treatment
combination. Barn was the experimental unit.
The model for all traits included housing environment, enrichment, and their interaction as
fixed effects, and traits with repeated measures
included barns as a random effect. Where applicable (i.e., feather scores and BW), individual
283
data from the 100 randomly sampled birds were
used per time period. Variances and covariances
among the repeated measurements on the same
barn were handled according to the method given by Wang and Goonewardene [24]. Linear and
quadratic orthogonal polynomial contrasts over
time were used to assess time trends and interactions of these with environment and enrichment groups were used to compare time trends
among experimental groups. Variances between
housing environments and between enrichment
groups were compared for all variables before
analysis using the Brown and Forsythe test. The
test indicated heterogeneous variances of feather
score between the housing environments, with
larger variances for the curtained environment.
Therefore, separate variances for the controlled
and curtained environments were incorporated
into the model for feather score.
For BW data, all treatments were not weighed
at the same day each week of age. Therefore,
days of age was used as a covariate in the analysis of BW data. Cull and mortality data were
converted to proportions before analyses. Behavior data expressed as counts were log-transformed + 1 to stabilize variances, after which no
further evidence of variance heterogeneity from
residual plots was observed. Raw means are reported. Differences were considered statistically
significant at P < 0.05.
RESULTS AND DISCUSSION
Culls and Deaths
In total, 1,432 mortalities (2.89% of population) occurred with an additional 1,164 culled
turkeys (2.35% of population); 58.78% of culls
and mortalities (1,526 turkeys) involved severe
pecking-related injuries. A significant effect of
housing environment on pecking-related culls
(P < 0.0001) and mortalities (P = 0.005) was
observed, with almost 80% of the culls and mortalities occurring in the curtain-sided barns (Figure 1); no effect of housing environment was
noted on nonpecking-related culls (P = 0.17) or
deaths (P = 0.12), however. Likewise, no effect
of enrichment on culls with severe pecking injuries (P = 0.61) or other culls (P = 0.24) was observed, and no effect on deaths with (P = 0.99)
or without (P = 0.38) severe pecking was noted.
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284
Figure 1. Effect of housing environment (controlled vs. curtain-sided barns) on culls (P < 0.0001) and mortalities (P
= 0.0045) with severe pecking injuries in commercial turkeys.
BW
Based on a significant enrichment × week
interaction, changes in BW over time differed
significantly between the 2 enrichment groups
(P = 0.045), with greater increases from wk 6 to
9 and 9 to 12 in the enriched group compared
with a greater increase from wk 6 to 9 in the nonenriched group. The linear trends may be influenced by housing, however, as a tendency was
observed toward interaction between enrichment
× housing × week (P = 0.094; Figure 2).
Feather Scores
Changes in feather scores over time differed
significantly between housing environments (P
= 0.0009), with turkeys housed in curtain-sided
barns having worse feather condition than those
housed in controlled barns. Both linear (P =
0.0005) and quadratic (P = 0.001) trends over
the weeks differed between the housing environments, with feather scores in the controlled barns
improving after wk 9, whereas those in curtainsided barns were worst at wk 15 (Figure 3).
No effect (P = 0.23) of enrichment on overall
feather condition was observed. However, turkeys in the enriched barns had better tail feather
condition (P = 0.003) compared with those in
nonenriched barns. An interaction between barn
and enrichment for neck feather condition (P
= 0.002) was noted. Enrichment had no effect
on neck feather condition when turkeys were
housed in controlled barns, but improved feather condition for turkeys in curtain-sided barns
(Table 1).
Behavior
An average of 4.5 ± 0.9 severe pecking bouts
occurred each observation period for the 60
turkeys observed (range: 0–23 bouts/observation period). A trend toward an effect of housing environment (P = 0.052) was observed, with
more severe bouts in the curtained-sided barns
(curtain-sided: 6.63 ± 1.57 bouts/observation
period; controlled: 2.38 ± 0.58 bouts/observation period). No effect of enrichment (P = 0.42)
nor any interaction between housing and enrichment (P = 0.36) was noted.
Duggan et al.: INJURIOUS PECKING IN TURKEYS
285
Figure 2. Effect of housing environment and enrichment on BW of male turkeys. An effect of week (P < 0.0001) and
enrichment × week interaction (P = 0.045) and a trend toward an enrichment × housing × week effect (P = 0.094)
were observed.
Figure 3. Effect of housing environment (controlled vs. curtain-sided barns) on feather scores over time (P =
0.0013) in commercial turkeys. Higher score denotes better feather condition.
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286
Table 1. Effect of growing environment on average feather scores by body region (least squares means score)1
Curtain-sided
P-value
Controlled
Body
region
Enriched
Not
enriched
Enriched
Not
enriched
Neck
Back
Tail
Wing
3.64 ± 0.02b
3.79 ± 0.01a
3.60 ± 0.02a
3.33 ± 0.02a
3.53 ± 0.02a
3.79 ± 0.01a
3.52 ± 0.02b
3.35 ± 0.02a
3.84 ± 0.02c
3.83 ± 0.01b
3.73 ± 0.02c
3.51 ± 0.02b
3.83 ± 0.02c
3.87 ± 0.01c
3.68 ± 0.02c
3.55 ± 0.02c
Environment Enrichment
<0.0001
<0.0001
<0.0001
<0.0001
0.0005
0.16
0.001
0.12
Environment ×
enrichment
0.006
0.13
0.48
0.56
a–c
Within a row, values without a common superscript differ, P < 0.05.
Feather condition for each body region was scored from 1 to 4, with 4 being best.
1
In each observation period, an average of 6.1
± 0.8 gentle pecking bouts was observed per 60
turkeys. Different linear time trends occurred in
the 2 housing environments (P = 0.014), with
a decreasing number of bouts over time in the
controlled barns but not the curtained barns (P
= 0.006; Figure 4). Different quadratic effects
also occurred in the 2 enrichment groups (P =
0.037; Figure 5). Turkeys without enrichment
performed more gentle pecking than those with
enrichment, except at 9 wk of age.
Object pecking bouts were rare, occurring
1.5 ± 0.5 times each observation period per 60
turkeys. No evidence was observed of any effect due to housing environment, enrichment, or
their interaction, or of time, although some indication of an environment × enrichment interaction was noted in the quadratic trends over time
(P = 0.059; results not shown).
General Discussion
Preslaughter mortality is a serious concern
in the turkey industry, in terms of both productivity and welfare. From a survey of producers,
Erasmus [8] discovered that up to 2% of light
Figure 4. Effect of housing environment on the development of gentle pecking in growing male turkeys. A week ×
environment effect (P = 0.006) was noted; less gentle pecking occurred in the controlled barns as the turkeys aged.
Data presented are raw means. Statistics were performed on log-transformed means.
Duggan et al.: INJURIOUS PECKING IN TURKEYS
287
Figure 5. Effect of enrichment on the development of gentle pecking in growing male turkeys. A time × enrichment
(P = 0.037) effect was observed. Data presented are raw means. Statistics were performed on log-transformed
means.
toms and 6% of heavy toms were euthanized onfarm annually, with a significant percent due to
injuries. The prevalence of pecking injuries on
carcasses is also considerable [25] and associated with other health problems, such as arthritis
and foot-pad problems [26]. However, very little
is known about injurious pecking in turkeys, and
less still in commercial environments, as quantifying behavior in large groups of turkeys is quite
difficult [27]. In the current experiment, we
aimed to examine the development of pecking
in 2 commercial environments with and without
occupational enrichment.
We found greater cull and mortality rates
and worse feather condition in turkeys housed
in curtain-sided barns compared with those in
controlled barns. The cull and mortality rates
are in line with previous experimental reports
[27–29], and the percent with severe pecking
injuries agrees with producer reports [8]. We
did not perform necropsies on culled or dead
birds, and therefore cannot ascertain whether
some birds became victims of pecking after dying from an unrelated issue, such as lameness or
illness. Regardless of the ultimate causal factor
of each death, mortality in toms still represents a
significant welfare issue. That culls and mortalities were higher in the curtain-sided barn is not
surprising, given the significantly greater light
intensity in those barns. Whereas the light intensities in both environments were much greater
than Barber et al. [30] found in a survey of 4 major British producers, the levels in the controlled
barns were lower than the breeder recommendation of 60 to 100 lx for growing toms [31].
However, researchers of previous reports have
correlated light intensity with injurious pecking
[30, 32, 33]; likewise, we found worse feather
scores in the curtain-sided barns.
Because turkeys prefer more intense lighting [30] and lighting more similar to daylight
in terms of spectral output [34], it is unclear
why the curtain-sided barns, with their natural
daylight, resulted in more culls and mortalities
with severe pecking injuries. It has been suggested that birds perform feather pecking as a
result of an inappropriate foraging environment
[28, 35, 36]. Commercial poultry housing can
288
be considered impoverished in terms of foraging outlets, although natural daylight should be
expected to improve the appearance of foraging material such as litter. Natural daylight is a
broad spectrum light source that includes UV
wavelengths that can be perceived by domestic
poultry [37]. However, it may be that while the
natural daylight in the curtain-sided barns improved the appearance of the foraging environment, it also influenced the appearance of feathers. Natural markings develop on the shoulders,
wings, tail, thighs, neck, breast, and dorsal surface of turkeys [35] and are thought to be important in the establishment of social hierarchies.
These markings are capable of reflecting UV
light and it is thought pecking may occur in enclosed environments because the lighting lacks
a UV component, distorting these markings and
causing frustration [28]. However, with the high
light intensities recorded in the curtain-sided
barns, these markings may have appeared more
vivid to the birds and provided a greater visual
stimuli. This suggestion agrees with the results
of Sherwin and Devereux [35], who found that
the age at which UV-visible markings appeared
on feathers coincided with the onset of pecking injuries. But, this may only be the case for
pecking directed at the feathers, as head pecking is considered to be aggressive in nature, and
may be completely unrelated to exploration and
foraging [7]. We did not differentiate between
severe pecking directed at the feathers or head,
and further investigations into the behavioral
patterns may help ascertain if they are similar
or if they differ in morphology and motivational
basis, such as is the case with gentle and severe
feather pecking [1].
Although lighting was assumed to be the
biggest difference between the 2 housing treatments, several confounds occurred that cannot
be discounted as influencing results. Differences
in stocking density and group size existed, although the stocking densities used in this facility were within the limits given by the Canadian
Codes of Practice [38]. Though reduced rearing
stocking density has been implicated with decreased productivity [27] and influences general
behavior patterns [39], no relationship has been
reported between density and injurious pecking [27, 40, 41]. Therefore, it is likely that, with
the large group size used in the present experi-
JAPR: Field Report
ment, early stocking density had a minimal effect. Poult placement also differed between the
2 housing treatments; poults were sourced from
the same hatchery but placed 5 wk apart. Both
hatchery and transportation factors related to
placement have been implicated in early poult
mortality [42], yet have not been studied with
regard to later mortality and may have confounded our results. Other variables, such as
humidity, ventilation, ammonia concentrations,
and litter condition, may also have varied between housing environments and influenced results, but these were not measured in the current
experiment.
The enrichment used in this experiment had
a limited influence on the results. An effect of
the balls on the development of gentle pecking
was noted and, when housed in the curtain-sided barns, turkeys without enrichment tended to
weigh less. However, the controlled barns had
more balls per bird than the curtain-sided barn,
and small statistical differences in pecking did
not translate into differences in feather condition or morbidity and mortality. The plastic
balls were originally chosen as enrichment due
to their durability and light weight, which prevented them from becoming buried within the
litter or being crushed or destroyed by squashing and pecking. Whereas chickens appear to
find balls stimulating [43], the balls in our experiment may have been an ineffective stimulus for turkeys for several reasons. As feather
pecking in chickens is proposed to be redirected
foraging behavior [1], foraging-type enrichment has been used to reduce feather pecking
in laying hens [13, 44]. The balls used in our
experiment were not friable and could not serve
well as foraging material. This may have limited their ability to reduce injurious pecking,
although it is unclear if pecking in turkeys follows the same motivational pattern as feather
pecking in chickens [7]. Researchers in only
a few studies have used enrichment as a way
to reduce injurious pecking in turkeys [9, 45,
46]. In the only study with enrichment devices
tested singularly, Crowe and Forbes [45] found
that novel objects were actually more successful at reducing pecking than foraging material.
However, novel objects are enriching so long
as they remain novel and do not elicit fear responses. We did not measure the turkeys’ use of
Duggan et al.: INJURIOUS PECKING IN TURKEYS
the balls specifically, but object pecking bouts
were rare with or without the balls. As the balls
were present at the start of the growing period
and remained throughout, it is probable that the
turkeys habituated to their presence and lost
interest in them, rendering them ineffective at
reducing injurious pecking. A critical period for
the introduction of enrichment to reduce pecking may also exist. Pecking injuries are observable in turkeys as young as 2 to 4 wk of age [9,
47], so it is conceivable that objects provided
to the poult, rather than the grower barns, could
have a more significant effect on the development of injurious pecking.
CONCLUSIONS AND APPLICATIONS
1. The majority of culls and mortalities in
this commercial turkey flock had evidence of severe pecking injuries, but
this was dependent on our experimental
treatments. Light intensity, stocking density, and poult placement factors should
be independently studied to determine
their effect on pecking in commercial
conditions.
2. Both severe and gentle pecking is apparent in tom turkeys as early as 6 wk
of age. Further research should focus on
understanding the underlying motivation
to mitigate pecking injuries.
3. Nonfriable, invariable enrichment did
not influence injurious pecking in this
commercial flock. Selection of enrichment devices should be based on the
motivation of the injurious behavior to
ensure that the enrichment increases
normal behavior, prevents abnormal behavior, and leads to positive interactions
with the environment.
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Acknowledgments
This study was supported by Agriculture and Agri-Food
Canada (Guelph, ON, Canada), the Canadian Poultry Research Council (Ottawa, ON, Canada), and the Poultry Industry Council (Guelph, ON, Canada). We are indebted to
the assistance of Lloyd Weber and the farm management at
LEL Farms (Guelph, ON, Canada) for making this project
possible. We also thank Ashleigh Arnone (Agriculture and
Agri-Food Canada), Krysta Morrissey, Sonia Holicova, and
Nancy Roulston (University of Guelph), as well as the many
volunteers who made data collection possible, and Alexandra Harlander-Matauschek (University of Guelph) for her
input on this manuscript.