Connection among Body Measurements and Flying Speed of Racing Pigeon†

Abstract

p>The ability of racing pigeons to navigate and to find their way home is determined by many factors. The aim of this investigation was to prove the outer and inner environmental impacts on the flying performances of racing pigeon flock. The fieldwork consisted of taking down of various body measurements of 49 birds, which was improved by collection of racing-, meteorological-, geographical-, and pedigree data.

According to the age corrected body measurements the birds of actual flock were longer in wing length, narrower in wing width and lighter in body weight than birds in Horn’s study. The breeding value for flying speed (BV speed) was calculated by an individual animal model taking the proven environmental effects (fixed: year of race, wind direction, rain fall, reproductive status; covariates: distance, temperature-humidity index) into consideration next to the genetic relatedness.

The BV speed showed significant association with the real flying speed only (r=0.71), and there were no statistically proven correlations with the body measurements and the body condition loss as well. While the wing length stayed in a closer negative connection (r=-0.40, p<0.05) to the loss in body condition.

Association of traits was further evaluated by use of factor analysis, from which it is concluded that the measurement responsible for body capacity, the measurements contributing the wing surface area, and the speed of bird are belonging to different determining groups (factors).

Over and above, from the investigation it can be concluded that the flying speed of the racing pigeon is not clearly determined by their body measurements, by their live weights and condition losses. However, the contribution of the body weight, chest depth (as breast muscle volume), and wing length to the flying success is strongly imaginable, which needs further research</p

Full text

International Journal of Agricultural
Science and Food Technology
ISSN: 2455-815X DOI CC By
009
Citation: Mercieca S, Jilly B, Gáspárdy A (2017) Connection among Body Measurements and Flying Speed of Racing Pigeon†. Int J Agric Sc Food Technol 3(1):
009-018. DOI: http://doi.org/10.17352/2455-815X.000016
Life Sciences Group
Abstract
The ability of racing pigeons to navigate and to fi nd their way home is determined by many
factors. The aim of this investigation was to prove the outer and inner environmental impacts on the
fl ying performances of racing pigeon fl ock. The fi eldwork consisted of taking down of various body
measurements of 49 birds, which was improved by collection of racing-, meteorological-, geographical-,
and pedigree data.
According to the age corrected body measurements the birds of actual fl ock were longer in wing
length, narrower in wing width and lighter in body weight than birds in Horn’s study.
The breeding value for fl ying speed (BV speed) was calculated by an individual animal model taking
the proven environmental effects (fi xed: year of race, wind direction, rain fall, reproductive status; co-
variates: distance, temperature-humidity index) into consideration next to the genetic relatedness.
The BV speed showed signifi cant association with the real fl ying speed only (r=0.71), and there were no
statistically proven correlations with the body measurements and the body condition loss as well. While the
wing length stayed in a closer negative connection (r=-0.40, p<0.05) to the loss in body condition.
Association of traits was further evaluated by use of factor analysis, from which it is concluded that
the measurement responsible for body capacity, the measurements contributing the wing surface area,
and the speed of bird are belonging to different determining groups (factors).
Over and above, from the investigation it can be concluded that the fl ying speed of the racing pigeon
is not clearly determined by their body measurements, by their live weights and condition losses. However,
the contribution of the body weight, chest depth (as breast muscle volume), and wing length to the fl ying
success is strongly imaginable, which needs further research.
Research Article
Connection among Body Measurements
and Flying Speed of Racing Pigeon†
Steven Mercieca1, Bertalan Jilly2 and
András Gáspárdy1*
1University of Veterinary Medicine, Department for
Animal Breeding, Nutrition and Laboratory Animal
Science, István str. 2., 1078 Budapest, Hungary
2Szent István University, Faculty of Economics and
Social Sciences, Institute of Regional Economics and
Rural Development, Páter K. str. 1., 2100 Gödöllő,
Hungary
†This paper is based on thesis Evaluation of the
connection among the body measurements and the
fl ying speed in a racing pigeon population written
by Steven Mercieca, a Maltese student at the Szent
István University, Faculty of Veterinary Science,
Budapest, Hungary 2013.
Dates: Received: 16 December, 2016; Accepted: 09
March, 2017; Published: 10 March, 2017
*Corresponding author: András Gáspárdy,
University of Veterinary Medicine, Department for
Animal Breeding, Nutrition and Laboratory Animal
Science, István str. 2., 1078 Budapest, Hungary,
Tel: +36-1-4784120; Fax +36-1-4784124; E-mail:
Keywords: Racing pigeon; Breeding value for fl ying
speed; Conformation; Temperature-humidity index
https://www.peertechz.com
Introduction and Aim
The homing pigeon (a variety of domesticated pigeon,
Columba livia domestica) has long been known for its impressive
ability to navigate through various terrains and fi nd its way
home, with speed being essential for a quick return when
racing. Several adaptations make birds solid and strong, yet at
the same time lightweight ‘fl ying machines’ [1]. Many external
factors are believed to have an effect on the fl ying speed and
thus racing performance of pigeons whereas others may not
affect speed or do so to a lesser extent. Such factors include
prevailing wind direction and speed, rainfall, sun visibility,
temperature-humidity index, temperature, health, disease,
husbandry and nutrition, training, familiarity and geography
of landscape.
The essence of a homing pigeon is its ability to navigate
and return home in the quickest manner and from distant
unfamiliar locations. Racing pigeons have long been used as
models for navigational studies and their homing ability has
intrigued many throughout the ages [2]. Besides the need
for good muscle functioning, a great variety of other factors,
including the wing quality, are present which determine the
suitability of a bird for racing according to speed. The wing
structure and characteristics are important in defi ning the
racing capacity of a bird, along with various other anatomical
traits. The speed of a pigeon is a critical part of the homing
ability together with overcoming many possible obstacles.
Both internal and external factors may infl uence the speed
and resultant performance of a bird and external ones include
meteorological, geographical and environmental factors
whereas internal factors include health, innate homing ability,
and stage of reproduction and body condition.

010
Citation: Mercieca S, Jilly B, Gáspárdy A (2017) Connection among Body Measurements and Flying Speed of Racing Pigeon†. Int J Agric Sc Food Technol 3(1):
009-018. DOI: http://doi.org/10.17352/2455-815X.000016
Once fl ight is initiated, different speeds may be attributed to
various fl ight modes. A free fl ying pigeon is capable of differing
fl ight modes including ascending, descending, turning, gliding,
horizontal fl ight, take-off and landing [3].
Pigeons are able to breed from the age of 6 months and can
do so all year, being most prolifi c in the spring and summer
months. They are monogamous and build fl imsy nests in
which 1-2 white eggs are laid after 10-15 days of pairing and
these are incubated for 17-19 days with the parents alternating
incubation once daily. After hatching, the parents raise the
squabs and these fl edge after 30 days or so. A second clutch is
usually laid during the rearing period of the fi rst pair of squabs
[4]. Racing of birds when they are in pre-breeding, incubation
or rearing reproductive stages has been postulated to affect
their speed and racing performance [5].
According to a study by Murton et al. [6], male birds are
thought to undergo behavioural changes as a result of changing
hormonal basis. Courtship is believed to be dependent on high
levels of FSH/androgen resulting in aggressive components of
the behaviour. The next phase is the nest demonstration and
higher oestrogen levels dominate it. At the end of this phase,
FSH dominated once more and results in nest building. Ball
and Balthazart [7] believe that ovarian oestrogens activate
female sexual behaviour and that parental care is hormonally
initiated by synergistic actions of sexual steroids and prolactin
in females, and by a response to the female’s signals in males.
The muscles are needed for wing movement, the chest
depth of a bird can be taken as the breast muscle volume. The
attachment of the m. pectoralis superfi cialis (aka m. pectoralis
major) is from the ribs, clavicle and lateral sternum to the crest
of the lateral tuberosity on the humours [8]. Its contraction on
the outside causes the wing to move downwards (downstroke,
Figure 1). The contraction of the m. pectoralis profundus (aka m.
pectoralis minor or m. supracoracoideus) will move the wing
upwards (upstroke, Figure 2). The tendon of this muscle runs
through a channel called the foramen triosseum formed by
the coracoid, scapula and clavicula allowing a pulley effect to
be achieved. The m. pectoralis major is rich in myoglobin and
muscle fi bres and also lipid droplets (most important source
of energy for pigeons when in continuous fl ight). It has the
greatest volume and surface area of the birds’ muscles and
is vital as a source of energy and for stamina during fl ight.
The m. supracoracoidues is paler in colour, contains more white
muscle fi bres and is rich in glycogen which is useful for sudden
manoeuvres such as take-off and landing. Since the upstroke
needs approximately one sixth of the exertion force of the down
stroke, the fact that there are less red muscle fi bres and less
lipids is of no real concern. The longer a race will be, the more
vital an appropriate supply of fat in the diet is. Protein is of less
importance than lipids and carbohydrates from an energetic
point of view. The importance of the m. pectoralis profundus
in uplift was investigated by Degernes and Feducia [9]. They
performed unilateral or bilateral tenectomy of the tendon of
this muscle to see if defl ighting would occur. Although none
of the birds undergoing either of these procedures had normal
dorsal extension of the affected wing, they were all still able to
escape and produce some uplift (though obviously not enough
to fl y appropriately). The pectoralis muscle force is seen to peak
at an early stage of the wing cycle during the downstroke [10].
The volume, tension and colour of the muscles are qualities
looked at in racing birds.
Wing quality is an important factor of evaluation when
racing pigeons are concerned. Feathers are one of nature’s
most prominent adaptations that enable birds to fl y. Many
requirements must be fulfi lled for successful fl ight such
as skeletal, muscular and aerodynamic ones. However the
mechanical constraints imposed by the forces of fl ight on
the feathers were not well explored. The peak strain on the
fl ight feathers occurs in the ‘foreward swing’ of the fl ight
cycle, at a point when the wings are supinated, adducted and
protracted at the same time. In this way, the ventral feather
surfaces are opposing each other in front and below the body
[10]. The wing and tail of a bird have feathers with a special
form and arrangement according to species [8]. The primary
fl ight feathers/remiges are the 10 feathers originating from the
region of the fi ngers and metacarpus (Figure 3). The secondary
feathers/remiges are those that originate from the lower
arm. Both groups of feathers are long and powerful with an
asymmetrical vane. The covering feathers are called coverts/
tectrices and these cover the fore- and hindwing. The alula/
spurious wing is the group of 3 feathers (small remiges and
their coverts) located on the thumb region of the wing and they
are controlled via their own small muscles. They are pressed
downwards when the bird is in fast horizontal fl ight but when
the angle of attack is increased, they help prevent the airfl ow
from becoming turbulent by acting as a forewing and are
also important as a braking mechanism. The tail of pigeons
is comprised of a number of stout steering feathers called
Figure 1: Contraction of the m. pectoralis profundus causes the wing to rise (after
Vansalen, 36).
Figure 2: Contraction of the m pectoralis superfi cialis causes the wing to move
downwards (after Vansalen, 36).

011
Citation: Mercieca S, Jilly B, Gáspárdy A (2017) Connection among Body Measurements and Flying Speed of Racing Pigeon†. Int J Agric Sc Food Technol 3(1):
009-018. DOI: http://doi.org/10.17352/2455-815X.000016
rectrices, with symmetrical vanes and their covering feathers
and is used as a steering organ in pigeons. The hind wing serves
mainly as airfoil with parameters like width and linearity of the
hind wing being checked when evaluating a bird. The forewing
functions mainly in propulsion. These feathers are deeply
imbedded in the wing bones, as they have to deal with a heavy
load during fl ight. They are subject to aerodynamic forces
during fl ight and the shafts will bend according to loads, with
the outer cortex being the most signifi cant structural feature
with respect to this bending [11]. The area and depth of the
outer vane of the fl ight feathers were notably smaller than the
inner vane and these were also stiffer in the pigeon than in the
barn owl, possibly showing that an increased load and strain
may be placed on these feathers in pigeons [12].
The body weight of pigeons was investigated by Kangas and
Branch [13]. They concluded that the body weight of male birds
could become stable after only 7 days of ad libitum feeding
whereas the female pigeons did not show this stability. The
hens showed consistently greater daily variation in weight
than the males even before egg laying, although less in this
period. The ideal shape of a bird destined to race is one that
offers least resistance and is aerodynamic. The deep keel of
some pigeons may mislead one to think that it will not be an
ideal fl ier however this deep keel is related to longer and more
precisely attached breast muscles. So heavy, deep-keeled birds
may actually be prized racing birds contrary to popular belief.
When compared to the human brain, the brain of pigeons
is relatively smaller compared to body size, mainly due to
the smaller cerebrum (with positive, conscious actions being
involved in this portion of the brain) as stated by Whitney [14].
The cerebrum is the part that responds most to training. It
is believed that once a pigeon learns what is wanted, and is
positively rewarded, each successive habitual act taught will be
easier to teach than the previous ones.
The sense of vision is undoubtedly vital for racing pigeons
and is believed to be far superior to that of mammals including
humans. The pigeon eye is fl atter than that of mammals,
limiting movement of the eyeball so they rely on head
movements to follow objects and other differences may be
implicated for movement perception. Pigeons have two visual
systems, frontal and lateral, which function differently and
objects moving between the two systems usually pose problems
in vision for the birds [15].
The pupillary size is linked to the nervous system and birds
with larger pupils have been noted to not be able to fi nish long
distance and/or diffi cult races. In short distance races the size
of the pupil is less important. The iris of a racing bird is fl at,
with few/no breeding lines and of uniform colour [16]. The
outer iris is covered by blood vessels, below which are the
radial muscles, which dilate the pupil upon contraction and is
dark and richly coloured. The inner iris is paler and contains
circular muscles and is indicated by the distance lines found
in this circle of correlation. Contraction causes constriction of
the pupil. The degree of pupillary constriction was found to
infl uence the racing speed, with birds having a greater degree
constriction fl ying faster than those with wider pupils [17].
The ability to return home from unfamiliar locations utilizes
various sensory cues both to determine the direction towards
home and to uphold their fl ight in that determined direction
having to fl y under a variety of conditions including opposing
winds, night time and in less than ideal weather conditions
[2]. The initial orientation of the birds and leadership by older,
experienced birds and other group effects were also noted when
mass releases of birds were done, with younger birds following
the older and more experienced ones [18].
Sun position and atmospheric odour and olfactory signals
are also believed to aid in homing with the birds shown to
integrate local odours at release site with various olfactory cues
picked up on transport [19,20]. The accepted hypothesis is that
if olfactory cues are lacking, the visualizing of the landscape
will determine the homing capacity and it is thus proposed that
the birds use a large aerial view of the landscape rather than
using multiple, small landmarks [21,22].
According to Schmidt-Koenig [23] the three subdivided
forms of homing are the following: piloting (use of familiar
landmarks in familiar territory), directional orientation (fl ight
along a fi xed compass bearing, with no use of landmarks and
may be wind error compensated or not), and navigation (fl ying
to a goal without use of landmarks). In a study by Wu et al.
[24], the results shown that relayed visual information may be
responsible for early warning of approaching objects whereas
other cells may signal an approaching object before impact
allowing appropriate avoidance responses. The presence of
magnetite-based receptors in the ethmoid region of the upper
beak proved to be signifi cant in the fi xed-direction responses
as opposed to the compass orientation [25].
Most birds fl ew almost at constant speed throughout the
fl ight and also consistently among the different days. When
the effect of crosswinds on homing direction were investigated
and tested, it was found that pigeons sometimes compensated
fully, occasionally even more than needed, for wind drift. Thus,
they could compensate quite precisely for crosswind error, but
usually maintain a preferred airspeed and do not increase or
decrease their speed for adjustment [26].
Figure 3: left wing of a pigeon showing the primary fl ight feathers (1), secondary
fl ight feathers (2), alula (3), coverts of the forewing (4), coverts of the hind wing (5)
and the shoulder coverts (6) (after Vansalen, 36).

012
Citation: Mercieca S, Jilly B, Gáspárdy A (2017) Connection among Body Measurements and Flying Speed of Racing Pigeon†. Int J Agric Sc Food Technol 3(1):
009-018. DOI: http://doi.org/10.17352/2455-815X.000016
Pigeons perform very poorly when they were unable to
see the sun and also in overcast/foggy conditions, especially
if released from novel sites. With proper training, birds may
also learn to home under the cover of nightfall [2]. Rainfall
may also affect the racing ability of pigeons. Conditions with
low, medium or heavy rainfall are commonly encountered in
races and birds are often seen to land and refuse to fl y in heavy
rain [27].
The temperature-humidity index (THI) was fi rst described
by Thom [28] and developed for humans and adapted to
cattle by e.g. Berry, et al. [29]. It is calculated according to the
temperature and humidity values recorded, using a specifi c
formula [30]. Results of this study showed that a THI of 68
was enough to adversely affect cattle by causing discomfort,
and as the values increased, production was affected. This
index was utilized in this study to see if a signifi cant effect on
performance was present.
Many other factors exist that affect racing performance. Poor
health in a fl ock may decrease speed and stamina when racing,
leading to poor performance. Protocols include vaccination
against Poxvirus, Paramyxovirus-1 and Salmonellosis and
anti-parasitic treatment such as annual deworming, year
round pyrethrin dusting and treating for Trichomoniasis
before racing and breeding periods. Many viral (Adenovirus,
Avian Poxvirus, Circovirus, Herpes virus, Paramyxovirus-1) diseases
may affect pigeons [31]. The most important Bacterial diseases
in a racing fl ock being: Salmonella typhimurium var copenhagen,
Escherichia coli and a group of bacteria causing chronic
respiratory disease and resulting in poor performance, made
up of Chlamydia psittaci, Pasteurella species and Mycoplasma
species. Additionally Fungal diseases, Parasitic diseases (e.g.
Coccidiosis, Haemoproteus, Trichomonas gallinae) and Ectoparasites
(e.g. Mallophaga, Hippoboscid pigeon fl ies) disturb birds and
cause stress them [32].
According to Frank [16], the eye of a healthy pigeon should
be clear, shining, observant and fully open. If illness strikes,
the eyes usually become dull, with possible drooping eyelids.
The aim of this study was to investigate various outer and
inner environmental impacts on the fl ying performances of a
racing pigeon fl ock of Jilly (in years 2011-2013). The fi eldwork
of this study consisted of taking down of various body
measurements of 49 birds, which was improved by collection
of racing-, meteorological-, geographical-, and pedigree data
as well as by comparison to the conformational data from
the doctoral work of Horn [5] written in 1935. The various
anatomical characteristics of the birds were measured and their
impact on speed and racing performance was investigated.
Materials and Methods
Forty nine birds were selected for the investigation and
various data was recorded on site at the breeder’s loft in
Gödöllő, Hungary. The pigeon breeder was Dr. Bertalan Jilly
(membership code B-01), one of the authors, who invited to
carry out this investigation. He is breeding a closed strain of
racing postal pigeon since 45 years which is based on two
initial pairs imported from Georges Fabry, Belgium, 1970. For
its continuous refreshment he gets newer individuals from the
following breeders: Delbar, Janssen, van Wanroy, de Weerd,
Marcelis, and Fulgoni. The age of the birds investigated ranged
from 1 to 7 years and the population consisted of 23 cocks
and 26 hens. The birds were all vaccinated on the 10th January
2013 against Paramyxovirus. The weather on the day of visit
(Friday 5th April, 2013) for data recording and collection was
overcast, with low rainfall (<10 mm) and an average daytime
temperature of 8°C.
The taking of various body measurements was used to
assess the birds. A measuring tape was used for wing length
measurement, from base of wing to tip of outermost primary
feather (Figure 4), as well as for wing width (from the dorsal tip
at the bend of the wing, above which one will fi nd the alula or
‘spurious wing’, to the tip of the fi rst secondary feather). The
primary feather length was also measured using the outermost/
last primary feather (Figure 5), together with the secondary
feather length using the length of the fi rst secondary feather
(inner most, before transition to primaries). The body length
was also measured from point of the shoulder to the tip of the
tail. Callipers were used to measure the chest width (widest
point of the chest from the inside of the wings, Figure 6) and
the chest depth (from the middle of the dorsum of the bird to
the deepest point of the sternum ventrally, Figure 7). The live
weight of each bird was measured using a tared (zeroed out)
digital balance, by placing them in a box. The birds were fed
last in the previous afternoon and not fed in the morning of
the investigation.
Figure 4: Measurement of wing length; photo Mercieca, 2013.
Figure 5: Measurement of outermost primary feather length; photo Gáspárdy,
2013.

013
Citation: Mercieca S, Jilly B, Gáspárdy A (2017) Connection among Body Measurements and Flying Speed of Racing Pigeon†. Int J Agric Sc Food Technol 3(1):
009-018. DOI: http://doi.org/10.17352/2455-815X.000016
Some of the body measurements taken down in this study
were corrected for 2 years of age (adjustment) in order to obtain
a parameter for this age as well as to make it comparable to
Horn’s results. The raw body measurements data (body length,
chest width, wing width, wing length and live weight) from
the doctoral work of Artúr Horn [5] were also taken over, and
involved as a control into the investigation. The populations of
birds used in Horn’s work consisted of 60 individuals.
The breeding value for fl ying speed (BV speed) was also a
parameter to be estimated. Since the speed was expressed with
its breeding value, its estimation is considered as a genetic
measure. The racing performances of all the investigated birds
were recorded for the racing period 2013 (May-July). For birds
older than 1 year, the racing performances from the racing
periods of the years 2011 and 2012 were also added to the
estimation. A total of 466 competitions were considered. The
racing data included: place of start, date of race, starting time,
time of arrival, duration of race, distance in meters, speed
(meters/min), body condition at start and body condition at
fi nish. Speed was calculated (dividing the distance fl own in
meters by the duration of the race in minutes) for the fi rst
60% of the birds, which arrived from every race. The distances
fl own for each race were also noted down and ranged between
160 km with the starting point being in Rajka, Hungary, and
760 km, for races starting from Magdeburg, Germany.
According to the opinion of Jilly, the body condition status
and change of the birds were integrated into the investigation.
The breeder gave the body condition on a scale from 1-5, with
5 being the best condition and 1 being very thin. The change
in body condition was calculated by subtracting the condition
at start from that at the arrival. To characterize the individual
birds, an average value for condition loss was used.
The impact of the breeding stage of the birds on the racing
performance was also proven. The incubation or rearing
status at the time of each race was therefore integrated. The
reproductive status was coded as follows: code 1 for birds
before nesting; code 2 for birds being in incubation; code 3 for
birds rearing squabs.
A code for sex was given, with male birds having code 1
and female birds having code 2. Meteorological data were also
collected for each race. These included: temperature at start of
race, temperature at end of race, wind speed, wind direction,
relative air humidity at start and at fi nish, and rainfall (if any).
A rainfall code was used: code 1 denoting no rainfall (0 mm),
code 2 denoting low or medium rainfall (0-25 mm) and code 3
denoting heavy rainfall (>25 mm).
A wind code was also used according to the prevailing wind
direction and its effect on the birds’ fl ight according to the
anticipated direction of fl ight. Code 1 - supporting winds or no
wind; code 2 – hindering or crosswinds.
The temperature-humidity index, THI was then calculated
using the temperature and humidity values collected. It was
done for the start and fi nish of each race and an average value
was also calculated, using the formula (30):
THI=DBT- [0.55 - 0.55 * RHum %] * (DBT - 58),
where: DBT = Dry Bulb Temperature (Fahrenheit), RHum%
= Relative Humidity.
Using an altitude map, the impact of elevations on the races
was investigated, as was advised by the breeder. The elevations
came in the form of hills and mountains. The most prominent
elevations were recorded and the sum of the elevations
calculated. A coding system was used for this too: code 1 – total
elevation of up to 500 m, code 2 – total elevation 500 m or
more.
All data was recorded on Microsoft Excel [33]. The impact of
the above effects was controlled by Statistica program package
[34].
The BV speed (breeding value for speed) for each fl ight
of each bird was calculated by using an individual animal
model, which is a by pedigree information improved BLUP-
method [35]. The model used only the statistically proven
environmental effects (fi xed: bird itself, year of race, wind
direction, rain fall, reproductive status; co-variates: distance,
temperature-humidity index at the end of the race) and
bird genetic relatedness to allow prediction of the animal’s
individual merit. Other impacts (sex, age at race, elevation of
landscape, loss in body condition, temperature at start and
wind speed) were checked for signifi cance but were excluded
from the fi nal model due to their insignifi cant impact on speed.
Figure 6: Measurement of chest width; photo Mercieca, 2013.
Figure 7: Measurement of chest depth; photo Gáspárdy, 2013.

014
Citation: Mercieca S, Jilly B, Gáspárdy A (2017) Connection among Body Measurements and Flying Speed of Racing Pigeon†. Int J Agric Sc Food Technol 3(1):
009-018. DOI: http://doi.org/10.17352/2455-815X.000016
The mean values and corresponding standard error for chest
width, chest depth and body weight which were adjusted to 2
years of age, and wing length and wing width were calculated.
The means for each parameter in actual (Jilly’s 2011-2013) and
in Horn’s (1935) population were compared using Student’s
T-test [36].
Then correlation coeffi cients were calculated to measure
the strength and direction of the association between the BV
speed and the age corrected body measurements.
Factor analysis was used to further analyse the association
of the age-adjusted traits using Statistica 12 [34] to determine
which parameters are statistically belonging together. The
main reasons for use of factor analytic techniques were to
reduce the number of variables and to detect structure in the
relationships between the variables. Therefore, factor analysis
is applied as a data reduction or exploratory structure detection
method.
Results and Discussion
The total least squares mean value for speed was 1012.9 m/
min. According to the BV speed, the best bird was the female
with ID HU 12-01-47930 (BV speed = +397.26) and the weakest
racing individual was the male with ID HU 12-01-47936 (BV
speed = -677.07). Jilly stated that a good bird was a blue male
with ID HU-07-01-98450 that had one good performance each
year and was culled out at 6 years of age. Its bloodline is present
in some individuals in the fl ock presently. The BV speed values
for these birds were in the upper range of the list (+112.72 and
+143.60, respectively) but also birds better than these existed
in the fl ock. The racing birds in the Jilly’s population are the
progenies only who serve with information for the breeding
parents. The selection practiced by him is called as recurrent
selection.
The reproductive stage has been thought to affect the
animals’ racing performance and speed for some time [5]. Horn
investigated the reproductive stage for each animal and each
race as was done in this study. The incubation or the rearing
day were recorded and believed to be important in racing
performance. It was postulated that birds in the incubation
or rearing phase of the reproductive cycle would be motivated
to return to the loft quicker, thus increasing their speed and
improving their performance as compared to birds out of these
reproductive phases. This was further investigated in this study
and statistically proven to have a signifi cant positive impact
on the investigated trait (speed) and was therefore used in the
fi nal individual model for calculation of BV speed along with
the other mentioned parameters.
The temperature-humiditiy index (THI) values were
generally higher at the end of a race. The reason for this is that
the index gives a larger impact of temperature than humidity.
At the start, there is hypothetically a lower temperature and
a higher humidity value but since the temperature is more
infl uential, the index is lower which is benefi cial. At the end
of the race, the higher temperature allows for a higher index,
which may prove to be a stressor. An index value of 83-84 or
higher is predicted to be a severe stressor for animals (the
primary study proved this on cattle at a much lower value of
67) so a negative effect on performance when such conditions
arose, would be noted. The index values ranged from 55.4–96.8
with the majority being below 84. Only the THI for the end of
the race was used as a covariate in the fi nal model for BV speed
calculation.
The mean values (and equivalent standard errors) from
the body measurements of Jilly’s fl ock compared to Horn’s
fl ock (Table 1) showed that the mean body weight of birds
was signifi cantly lower in the present data (475.8 g) than in
Horn’s fl ock (488.2) with a p-value of 0.03. The mean values
for chest width and wing width proved to be signifi cantly
lower in the present data (p<0.01) whereas chest depth showed
no signifi cant difference between the two samples having a
value of 7.16 cm in both (p=0.96). The mean values of primary
feather length, secondary feather length and body length were
tabulated for the present study only having mean values of
17.02 cm, 9.25 cm and 24.68 cm, respectively.
Horn [5] performed a similar experiment to the one
presented here. His birds ranged from 1-5 years of age and he
believed that age and sex both infl uence racing performance.
The anatomical measurements recorded by Horn varied slightly
from the ones done here. The body length was measured from
the tip of the shoulder to end of the rump thus he took the
real anatomical bony trunk into account. In this study the body
length was measured till the tip of the tail. For this reason
comparing measurement results from the two studies would
give erroneous p values, hence it was excluded. The chest width
was measured by taking the whole width of the animal, from
the lateral surface of the left wing to that of the right wing (of
a bird in hand, with closed wings) in Horn’s study as compared
to this work were the anatomical chest measurement excluding
the lateral wing surfaces was done. The wing width, wing length
and live body weight before feeding were done in the same way
as Horn’s technique, although the weight measurement was
done to 5-gram accuracy in Horn’s work compared to the 1 g
accuracy in this study.
The comparison of mean values obtained from the measured
body parameters for wing width, wing length and body weight,
had signifi cant p-values and showed that the sample of the
present day study were on average 12.4 g lighter, had a wing
Table 1: Base statistics and comparison of body measurements.
Body measurements Horn, 1935
(n= 60)
2013
(n= 49) p-value
Mean SEM Mean SEM
2-year body weight 488.2 3.75 475.8 4.15 0.03
2-year chest depth 7.16 0.04 7.16 0.05 0.96
2-year chest width 9.66 0.08 6.73 0.09 <0.01
Wing length 27.96 0.13 30.44 0.15 <0.01
Wing width 12.31 0.13 11.11 0.15 <0.01
Last primary feather length - 17.02 0.18
2- year 1st secondary feather length - 9.25 0.06
2-year body length - 24.68 0.12

015
Citation: Mercieca S, Jilly B, Gáspárdy A (2017) Connection among Body Measurements and Flying Speed of Racing Pigeon†. Int J Agric Sc Food Technol 3(1):
009-018. DOI: http://doi.org/10.17352/2455-815X.000016
length that was on average 2.48 cm longer and a wing width
that was on average 1.2 cm narrower than the birds measured
in Horn’s study. This is possibly explained as an evolutionary
change (obtained by selective breeding) to make the birds
lighter, and longer in the forewing and narrower in the hind
wing that may allow better performance by moving towards
creating a ‘speedy’ type of bird. Due to fi nancial rewards
offered to the owner of the fastest pigeon, selection for those
pigeons that home the fastest may be a determining reason for
this [2].
The chest depth showed no signifi cant difference between
the two samples allowing the present day birds to still have
a deep chest (body capacity) needed to for fl ight. Thus, the
birds of Horn’s study appeared to be stockier, heavier, shorter
and wider in the wing with a comparably smaller chest depth.
The chest widths were compared and had a larger value in
Horn’s data (2.93 cm wider) predictably so due to the various
measuring techniques in the two studies. The mean values for
last primary and 1st secondary feather length were measured
for the present study only. The outermost primary feather
length mean value was 17.02 cm, lower than the mean length of
19.3 cm as described by Bachmann et al. [12]. The body length
of the birds was also measured differently in the two studies,
so a comparison was not done. The body length in the present
data had a mean value of 24.68 cm. Although body type was
mentioned, the breeder of the sample of birds used in this
present study does not use an evaluation system for body type,
and birds of all types (deep keeled, longer or shorter in the
wing, heavier or lighter etc.) are raced altogether and in the
various race distances. More attention is paid to the health, eye
evaluation and general condition of the animal to determine
the racing capacity.
In many cases the correlation coeffi cients (Table 2) among
the variables were low and non-signifi cant (r<0.31 and
p>0.05). In fewer cases statistically proven associations were
found. The majority of them were positive and showed medium
strong association such as the connection between the body
weight adjusted to 2 years of age and the wing length (r=0.32
and p<0.05). Strong association was found between the BV
speed and the real fl ying speed (r=0.71) and between the body
weight and chest depth (r=0.67). The only signifi cant proven
association of BV speed was to the real fl ying speed, without
any signifi cant relation to the body parameters. The body
length showed positive association with the 2-year body weight
(r=0.46), chest depth (r=0.48), 1st secondary feather length
(r=0.44), and wing width (r=0.41). Strong negative correlation
(r=-0.58) was found between the last primary feather length
and wing width. Out of this, the last primary feather length
had positive relationship (r=0.36) to the wing length only. The
second strongest negative association (r=-0.40) was between
the wing length and the body condition loss. It was also noted
that wing width did not have a signifi cant association (r=0.13)
with wing length.
The BV speed showed a strong signifi cant positive
association with the real fl ying speed only with no statistically
proven correlation with the body measurements and the body
condition loss.
The majority of body condition loss associations were not
signifi cant except for the negative correlation to wing length
(r=-0.40). As the wing length value increases, a decrease in
body condition loss is expected. Perhaps a longer wing allows
the bird to maintain fl ight and better utilize stored energy,
allowing a better overall condition upon returning from a race.
In fact, condition losses ranged from mild to strong and are
dependent on many other racing factors. The breeder objectively
assessed the body condition before and after each race for each
bird using visual examination and tactile palpation. Another
proven negative association, albeit stronger, (r=-0.58) was
found between the primary feather length and wing width. As
the primary feather length increases, the width of the wing is
seen to decrease. Perhaps this is an evolutionary trait allowing
birds to have longer and narrower wings. The body length
showed positive associations with r-values ranging from 0.41
(wing width) to 0.48 (chest depth). An increased body length
Table 2: Correlation coeffi cients (r) between variables (n = 38; marked correlations are signifi cant at p<0.05).
Variable Means Std.
Dev.
Body
condition loss
(1)
Breeding
value for
fl ying speed
(2)
Flying
speed
(3)
2-year
Body
length
(4)
2-year
Body
weight
(5)
2-year
Chest
depth
(6)
2-year
Chest
width
(7)
2-year 1st
secondary
feather length
(8)
Last
primary
feather
length
(9)
Wing
width
(10)
Wing
length
(11)
(1) -1.29 0.45 1.00 0.28 0.26 -0.02 -0.03 -0.04 0.02 -0.16 0.06 -0.22 -0.40*
(2) -0.81 172.8 0.28 1.00 0.71* 0.00 0.10 0.23 -0.05 0.04 0.19 -0.03 0.19
(3) 1270.21 324.0 0.26 0.71* 1.00 0.16 0.04 0.09 0.20 0.12 0.09 0.15 -0.07
(4) 24.74 0.85 -0.02 0.00 0.16 1.00 0.46* 0.48* 0.22 0.44* 0.13 0.41* 0.31
(5) 473.97 35.02 -0.03 0.10 0.04 0.46* 1.00 0.67* 0.30 0.20 0.27 -0.05 0.32*
(6) 7.18 0.30 -0.04 0.23 0.09 0.48* 0.67* 1.00 0.33* 0.39* 0.23 0.11 0.51*
(7) 6.70 0.74 0.02 -0.05 0.20 0.22 0.30 0.33* 1.00 0.13 -0.12 0.04 -0.30
(8) 9.28 0.42 -0.16 0.04 0.12 0.44* 0.20 0.39* 0.13 1.00 0.25 0.37* 0.39*
(9) 17.09 1.30 0.06 0.19 0.09 0.13 0.27 0.23 -0.12 0.25 1.00 -0.58* 0.36*
(10) 11.16 1.22 -0.22 -0.03 0.15 0.41* -0.05 0.11 0.04 0.37* -0.58* 1.00 0.13
(11) 30.58 1.02 -0.40* 0.19 -0.07 0.31 0.32* 0.51* -0.30 0.39* 0.36* 0.13 1.00

016
Citation: Mercieca S, Jilly B, Gáspárdy A (2017) Connection among Body Measurements and Flying Speed of Racing Pigeon†. Int J Agric Sc Food Technol 3(1):
009-018. DOI: http://doi.org/10.17352/2455-815X.000016
meant a larger bird, which predictably showed an increase in
body weight (r=0.46), however, it also correlated to increases
in wing width, chest depth and secondary feather length
(r=0.44). Increase in body weight was strongly correlated to an
increase in chest depth (r=0.67) but showed a medium strong
correlation to wing length (r=0.32). Perhaps a heavier bird
needs a deeper chest and longer wing to compensate for the
increased weight allowing fl ying performance to be maintained.
It was interesting to note that there was no strong positive
association between the wing width and wing length (r=0.13).
The chest depth showed the strongest positive associations with
other traits including wing length (r=0.51) and 1st secondary
feather length (r=0.39). Perhaps the presence of a deeper chest
required the wing and fl ight feathers to be longer in order to
maintain proper uplift during fl ight. With this, chest depth and
width were also in positive correlation (r=0.33) though not as
strongly as would be expected. The secondary feather length
showed a medium strong positive association to the wing width
(r=0.37) and wing length (r=0.39). An increase in wing length
and wing width requires an increase in the secondary feather
length though this relationship is not as strong as expected.
Besides the negative association mentioned previously, the
primary feather length shows a medium strong association to
wing length (r=0.36). This is expected, as the forewing of a
pigeon is largely comprised of the primary fl ight feathers so
a parallel increase in both can be seen. Wing width and body
length are positively associated (r=0.41) meaning most birds
with longer bodies also had wider wings allowing a larger wing
surface area (hind wing) to aid in uplift of an expectedly larger
bird. In respect of body weight Bhowmik et al. [37] calculated
stronger correlation coeffi cients between body weight and
body length, and wing length (wing span) (r=0.74 and 0.71,
respectively) in Jalali Pigeon, a lighter bodied local breed of
Bangladesh; the reason for difference might be our adjustment.
Using factor analysis, the factor loading (varimax
normalised) of the traits into different determining groups was
done, with factor weights >0.70 taken as signifi cant (p<0.05) as
shown in Table 3. It was found that the eight traits investigated
were put into four factors including those measurements
responsible for ‘body capacity’ (body weight, body length and
chest depth), the measurements contributing to the ‘wing
surface area’ (wing width and last primary feather length,
but merged together with the factor containing wing length)
and the ‘speed of bird’. These traits are therefore belonging
to different determining groups (factors) with a majority of
positive factor weights being noted, together with a single
proven negative association. The proportion total of these
factors gives an explained variance of 73% for the parameters
with a decreasing order (factor 1 = 25%, factor 2 = 17%, factor
3 = 16%, factor 4 = 15%). The remaining 27% is unexplained
variance.
Determining which parameters are statistically proven to
belong together according to the results obtained would help
to reduce the higher number of known correlated variables to
fewer unobserved factors. The main reasons for use of factor
analytic techniques were to reduce the number of variables and
to detect structure in the relationships between the variables,
actively classifying them. Therefore, factor analysis is applied
as a data reduction or exploratory structure detection method.
The signifi cant variables belonging to factor 1 were body
length, body weight and chest depth with values of 0.73,
0.80 and 0.85 respectively. The positive, proven statistical
association of these traits into factor 1 shows that these related
traits could be responsible for the ‘body capacity’ of the bird.
Since these traits belong to one factor, this encompasses the
anatomical trunk (depth) and weight of the bird together with
the length, and their relatedness, which means that if one
of them increases, a parallel increase should be noted in the
others.
The signifi cant variables belonging to factor 2 included the
BV speed and the fl ying speed, resulting in the factor being
called the ‘speed’ factor. The positive and signifi cant factor
values were 0.90 and 0.89 respectively. This shows that the
BV speed calculated using the individual animal model is
positively associated to the calculated fl ying speed of the birds.
Thus as the merit of the animal increases, as calculated by the
breeding value, a parallel increase in speed is seen. All other
variables taken into consideration for this factor showed either
insignifi cant positive or negative factor values meaning that
the real speed and breeding value for speed are independent
from the body characteristics of the birds.
The signifi cant variables belonging to factor 3 allowed it
to be termed the factor for ‘wing surface area’. These included
primary feather length and wing width (placed in close
association with the wing length in factor 4). The factor values
were -0.72, 0.93 and 0.82 respectively. The proven positive
associations (0.93 and 0.82) show that an increase in the
factor value resulted in an increase in the wing width and wing
length. A single, proven negative association (-0.72) was seen
with primary feather length in factor 2. Strengthening this, the
correlation between the primary feather length and the wing
width (Table 2) was also negative. This showed that with an
increase in the factor value there was a decrease in the primary
feather length.
In a study comparing the wings of pigeons and barn owls
by Bachmann, et al. [12], the wing area of the barn owl was
Table 3: Factor weights of traits by different determining groups (n = 38; marked
correlations are signifi cant at p<0.05).
Traits Factor 1 Factor 2 Factor 3 Factor 4
Body condition loss -0.11 0.48 -0.25 -0.48
Breeding value for fl ying speed 0.06 0.90* -0.11 0.41
Flying speed 0.11 0.89* 0.14 -0.10
2-year body length 0.73* 0.07 0.27 0.09
2-year body weight 0.80* -0.03 -0.27 -0.06
2-year chest depth 0.85 0.10 -0.10 0.11
2-year chest width 0.52 -0.02 0.12 -0.68
2-year 1st secondary feather length 0.55 0.08 0.25 -0.38
Last primary feather length 0.27 0.16 -0.76* 0.33
Wing width 0.19 0.06 0.93* 0.17
Wing length 0.42 0.00 -0.09 0.82*

017
Citation: Mercieca S, Jilly B, Gáspárdy A (2017) Connection among Body Measurements and Flying Speed of Racing Pigeon†. Int J Agric Sc Food Technol 3(1):
009-018. DOI: http://doi.org/10.17352/2455-815X.000016
found to be much larger than that of the pigeon. Having similar
weight, the wing area loading of the pigeon is higher, meaning
that they are not able to fl y slowly as a barn owl can. Barn owl
feathers were larger than pigeon feathers indicating a lower
wing load that would allow this slow fl ight. The loading of the
wing in pigeons was thus higher showing that their energy
expenditure would be greater in these birds. From the analysis
of feather morphology modelling made by Sullivan et al. [38],
it has been confi rmed that the interlocking adherence of barbs
to one another in pigeon will lead to a diminished barb rotation
during defl ation and an even stronger structure.
Conclusions and Recommendations
The breeding value estimation calculated using an individual
animal model, is a relatively new and unexplored fi eld for
pigeons and has only received acceptance and practice on farm
animals. For pigeons, local breeders have only calculated the
actual speeds. Thus, further investigation into the breeding
value estimation is recommended.
When comparing the results of this study to the data of
Horn’s work (1935), the wing lengths in the population of the
present study were greater than those of Horn’s population
and no association between the wing length and wing width
was found. It was also noted that the greater the wing length,
the lower the body condition loss. This automatically proves
the selection for longer distance for the present population.
Although no bird body type evaluation was done in this work, it
could be concluded that present day birds are more specialised,
performance oriented, more appropriately fed, healthier and
have greater outer and inner environmental support leading
to their improved performance. The proven changes in the
conformation of the birds shows that they have become more
athletic than the heavier, shorter winged birds from the early
20th century according to the population comparison.
Overall, by the lack of signifi cant associations, it can be
concluded that the fl ying speed of a racing pigeon cannot be
accurately determined according to the body measurements,
wing parameters, live weights and average body condition
losses. Thus it can be said that fl ying speed is largely
independent from the shape and size of the pigeons. However,
with regards to wing length, live weight and chest depth (as
breast muscle volume), we can imagine a special importance in
the fl ying and racing success.
Jilly’s 40 years of experience [39,40] strengthens our
fi ndings: longer wings result in higher speeds and lower body
condition losses. He explains this observation by discussing
that the body weight disperses better over a larger wing
allowing the bird to access greater forces for better fl ight.
With this proven idea, more signifi cant advice can be given to
other pigeon breeders. A recommendation would be for further
studies regarding creating an estimation model were various,
simultaneous traits can be integrated into a body index that
will possibly allow better correlation to the fl ying speed as
compared to the relations of individual traits to the BV speed
done here. This will potentially allow better estimation of
fl ying speed.
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