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296
landtechnik 69(6), 2014
LIVESTOCK AND MACHINERY
received 13 August 2014
accepted 21 Oktober 2014
Keywords
Outdoor cattle, rifle shooting, stress-free slaughter,
stun quality
Abstract
Landtechnik 69(6), 2014, pp. 296–300, 4 figures, 1 table,
9 references
n
The perennial outdoor keeping of cattle confronts the herd
management with different requirements than keeping cattle
inside the barn does. The relationship between man and ani-
mal is clearly less profound and outdoor-cattle generally keep
a higher distance towards humans than e.g. dairy cows do. Es-
pecially when it comes to slaughter, stress-induced meat qual-
ity impairment (e.g. DFD-meat) is well known. Transportation,
waiting time at the abattoir as well as restraining of the head
before stunning can lead to strain and do not support animal
welfare [1, 2, 3].
Slaughter via gunshot on the pasture
The on-farm slaughter method via gunshot directly on pastures
provides an alternative to regular stunning methods at abat-
toirs, where a captive bolt is generally used in order to stun the
animal. The animals gets stunned and killed immediately on the
pasture by a targeted shot from a hunting rifle. The withdrawal
of blood on-site follows promptly. Then, the carcass gets trans-
ported in a suitable transportation vehicle to the closest pos-
sible slaughter house for further processing. According to the
“Tierschutz-Schlachtverordnung” (“regulation on the protection
of animals at slaughter or killing”, Annex 1 to section 12 Article
3 and 10) in Germany this slaughter method can be applied [4].
However, it is only permitted to stun or slaughter cattle via gun-
shot if the cattle is reared on pasture all year round. Contrary
to the decree (EG) No. 853/ 2004 (Annex III Section I Chapter
IV Number 2 Letter b) [5] and after amending section 12 of the
“Tierische Lebensmittel-Hygieneverordnung” (“regulation on
hygiene regarding production, treatment and sale of certain
foodstuffs from animal origin”) in November 2011 [6] it is per-
mitted to slaughter grazing cattle on the farm of origin prior to
transport the carcass to the abattoir. A permit to slaughter on
the farm must be requested at the responsible authority.
Projectile Requirements
According to the supranational regulation on the protection
of animals at the time of killing (VO EG No. 1099/ 2009) the
projectile’s caliber and the impact energy of the targeted bullet
shot need to provide an efficient stunning potential to provide
instant death [7]. However, there are no further specifications
regulated by law concerning caliber and projectile apart from
mentioning the position of the shot, the power and calibre of
the cartridge and the type of the projectile as key parameters.
This lack of specification often leads to uncertainty.
Hunting weapons are ideal for stunning and slaughtering
cattle via gunshot [8]. The cattle has to be induced into an im-
mediate state of complete unconsciousness and loss of sensi-
bility. Therefore, the animal receives a shot to the head, and
not to the body as it is practiced in hunting. The aim of using
Retz, Stefanie; Schiffer, Katrin Juliane; von Wenzlawowicz, Martin and Hensel, Oliver
Stunning effect of different
rifle-bullets for slaughter
of outdoor cattle
The slaughter method via gunshot implies a stunning of cattle by means of a targeted shot
from a rifle and is as an alternative to regular slaughter at abattoirs. This method is only per-
mitted under restricted circumstances and if the cattle is held on a pasture all the year. How-
ever, there is a considerable lack of specifications regulated by law concerning calibre and
bullet-type. In this study, four different calibres, two bullet-types and two different shot place-
ments were investigated with respect to their stunning efficiency. All of the calibres exhibited
an entry-energy over 400 J and provided sufficient stunning potential. Yet, only calibre .22
Magnum caused no exit of the bullet out of the scull, which provides higher safety conditions
for man and cattle.
landtechnik 69(6), 2014
297
a bullet shot is to inflict severe and irreversible damage to the
brain. The damage is visible in pronounced bleedings and the
destruction of the brain tissue. A short-term pressure increase
within the cranial vault when the bullet hits and penetrates
the skull is crucial. If the bullet contains too much energy, it is
likely to exit the skull. As a result, bullet splinters could enter
the carcass, leading to a reduction in meat quality. Bullets con-
taining lead are especially critical. A bullet that exits the skull
is a hazard to man and cattle standing close by. The optimal pro-
jectile can be determined by analyzing the parameters “impact
of destruction” and “minimal invasive bullet reaction”.
The advantage of soft point bullets compared to full metal
jackets is that they expand their surface when they hit the target
and release more energy into the tissue. This is vital for a suf-
ficient destruction in the brain if the bullet remains in the skull.
A study of the University of Kassel, Department of Agri-
cultural Engineering [9] investigated which amount of energy
is necessary to penetrate a bovine skull successfully in order
to induce serious and irreversible damage to the brain at the
same time trying to keep the risk for man and cattle as low as
possible.
Animals, material und methods
In 2012 37 bovine skulls of German Angus (n = 33, of these
14 bulls and 19 cows) and Galloway (n = 4, all ox) were collected
from two farms in northern Germany. The cattle was held out-
door all year. Electrical stunning was used prior to slaughter
and the collected skulls were frozen at the abattoir. By using
electrical stunning the skulls stayed unmarked by bullet holes.
The skulls were thawed at room temperature approximately
48 hours prior to the treatment. The mean age of the animals
was 20 ± 10 month with a range from 7 to 44 month. One cow
was already ten year old, but the skull was similar to the others.
The high inhomogeneity of the examined cattle was inevitable
due to the varying slaughter management systems of the coop-
erating farmers.
Overview of used calibers and bullets
Kaliber
Caliber
Einschussposition
Shot placement
Geschoss/bullet
Rasse
Breed n
Hersteller, Art
Manufacturer, type
Durchmesser
Diameter
[mm]
Gewicht
Weight
[g]
V0–V1001)
[m s-1]
E0–E1001)
[J]
9.3 x 62 frontal PPU, Teilmantel/semi metal jacket 9,3 18,5 695-600 4470-3360 Dt. Angus 4
.30-06 frontal RWS, bionic yellow, bleifrei/lead-free 7,6 10,0 885-760 3915-2880 Dt. Angus 5
.30-06 frontal RWS, bionic black, bleifrei/lead-free 7,6 10,0 885-760 3915-2880 Dt. Angus 6
.30-06 lateral RWS, bionic black, bleifrei/lead-free 7,6 10,0 885-760 3915-2880 Dt. Angus 6
.30-06 frontal Barnes, TTSX, bleifrei/lead-free 7,6 10,9 850-790 3940-3360 Dt. Angus 2
.22 Hornet frontal PPU, Teilmantel/semi metal jacket 5,6 2,9 770-550 865-460 Dt. Angus 5
.22 Hornet lateral PPU, Teilmantel/semi metal jacket 5,6 2,9 770-550 865-460 Dt. Angus 5
.22 Magnum frontal CCI, Hohlspitz/hollow-point 5,6 2,6 580-400 440-210 Galloway 4
1) V0–V100 ist die Geschwindigkeit des Geschosses an der Laufmündung und nach 100 m Entfernung. E0–E100 ist die Energie des Geschosses an der Laufmündung und nach
100 m Entfernung/V0–V100 is the velocity of the bullet at the muzzle and after a distance of 100 m; E0–E100 is the energy of the bullet at the muzzle and after a distance of 100 m.
Table 1
Shooting stand for the shooting of the heads
Fig. 1
4 m
15 m
298
landtechnik 69(6), 2014
LIVESTOCK AND MACHINERY
The skulls were shot at with different rifles in order to test
varying calibers and bullet types. The choice of caliber was
based on the experience of gunmen who had worked with gun
shots on cattle before. The different calibers were 9.3 x 62 and
30.06 (big bore) as well as .22 Hornet and .22 Magnum (small
bore) (Table 1). All calibers used were soft point bullets. The
caliber 30.06 was differentiated in deformation bullets (bionic
black, Barnes TTSX) and fragmenting bullets (bionic yellow).
It was only possible to shoot at the Galloway skulls with the
caliber .22 Magnum due to permit and operational reasons.
The defrosted skulls were positioned on sandbags in front
of a bullet trap made out of sand in a 90° angle to the shooter
(Figure 1). The shooter stood on a 4 m high platform. The dis-
tance between the muzzle and the skull was 15 m. From this
distance it is realistic to shoot cattle for certain. The skulls were
frontally shot on the optimal point of entry. This point is 2 cm
above the intersection point of eyes and horn attachment (Fig-
ure 2). The mean thickness of the cranial bone at the frontal
point of entry was 1.4 ± 0.5 cm. In addition, skulls were shot
from the side with the calibers .30-06, bionic black and .22 Hor-
net. This was performed in order to test the practicability and
accuracy of the alternative point of entry.
The optimal point of entry was marked on each skull with
paint before the shot. After each shot the deviation of the bul-
let’s entry to the prior marked point was analyzed and it was
assessed whether the bullet had stayed in or exited the skull.
The bullet splinters that exited the skull were collected from
the bullet trap, cleaned and weighed. If the bullet stayed in the
skull, the penetration depth was measured with the means of a
probe. Afterwards, the skull was opened and examined on tis-
sue damage by an expert veterinarian.
Based on the prior experiments with the bovine skulls, cat-
tle were stunned and killed by a bullet shot on the same farms.
Five German Angus were shot with the caliber 30.06 and
13 Galloway with the smallest caliber .22 Magnum and slaugh-
tered subsequently. The stunning efficiency was assessed right
away using the method of Atkinson and Algers [2]. Evidence
for a good stunning efficiency is the absence of respiration, the
lack of eye movement and reflexes and the absence of directed
motor functions. These skulls were examined by an expert vet-
erinarian as well.
Results and discussion
It was observed that all caliber except the .22 Magnum (0 %
bullet exits) caused a 100 % exit of the bullets, if shot frontally.
The mean depth of penetration of the caliber .22 Magnum was
12.1 ± 1.9 cm. The bullet was always retrieved in the caudal
region of the cranial bone nearby the canal of the spinal cord.
If the skull was shot from the side with the small caliber .22
Magnum no bullet splinters exited the skull and with the larger
caliber 30.06, bionic black 43 % bullet splinters exited the skull.
If the bullet fragments left the skull, a large part of the pro-
jectile’s mass could be found outside of the skull (Figure 3).
The heaviest bullet fragments retrieved from the bullet trap be-
longed to the caliber 9.3 x 62 with an average of 12.4 g of the
18.5 g original weight. The highest percentage with 98 % of the
exiting bullet mass was found in the deformation bullet 30.06
TTSX. The bullet’s head had fully expanded but nearly stayed
in one piece when it exited the skull (Figure 4). The fragment-
ing bullet 30.06 bionic yellow had the least weight losses with
56 % in the caliber category 30.06. The smallest caliber with
exiting bullet fragments was the .22 Hornet. It exhibited the
least weight loss (37 %) after an exit with an average of 1.1 g of
the original 2.9 g. The safety for man and cattle is principally
higher if no bullet and bullet fragments exit the skull at all.
Weight losses potentially greater than 6 g of bullet splinters
Optimum shot placement, frontal and lateral
Fig. 2
Weight of retrieved bullets after shooting and percentage of exited
material
Fig. 3
%Materia n=
9,3x62(fro
n
33,05622 5
30.06,TTSX1,151376 2
30.06,bioy
e
44,46067 6
30.06,biobl 19,33714 7
30.06,biobl 31,755 2
.22Hornet(
f
62,71264 6
.22Hornet(
l
0
.22Magnu
m
0
0 5 10 15 20
9,3 x 62 (front.)
30.06, TTSX (front.)
30.06, bio yellow (front.)
30.06, bio black (front.)
30.06, bio black (lat.)
.22 Hornet (front.)
.22 Hornet (lat.)
.22 Magnum (front.)
Geschossgewicht [g]
Gewicht nach Schuss
weight after shot
Gewicht vor Schuss
weight before shot
0%
0%
37%
68%
78%
56%
98%
67%
Weight after shot
Weight before shot
Weight of the bullet [g]
Fig. 4
Bullet 30.06 TTSX after shooting (Photo: S. Retz)
landtechnik 69(6), 2014
299
containing lead in the carcass are considered risky in terms of
food hygiene.
All frontally tested calibers featured massive destruction of
brain tissue at the examinations of the skulls. The tissue de-
structions were less expressed with the caliber .22 Magnum but
it always completely penetrated the brain. The bullet remained
in the cranial cavity leading to the assumption that it released
its complete energy to the brain. Based on the amount of energy
at the muzzle E0 = 440 J, at a distance of 15 m (E15) this means
a complete release of estimated E15 = 440 J to the skull. These
accelerating forces inside the skull lead to extensive traumata
of the brain. As specified by the manufacturer, a captive bolt
disposes an amount of energy of about 300–600 J, depending
on the animal that is about to be stunned. However, the velocity
of the bolt is below 100 m/s. For adult cattle with a live weight
between 450 and 900 kg an energy of approximately 400 J has
been proven sufficient for stunning. This shows that the calibre
.22 Magnum is in the range for sufficient stunning. In the case
of old and heavy bulls and in the case of doubt a slightly bigger
load should be used. The bigger calibre .22 Hornet features a
higher velocity at the muzzle and therefore an amount of en-
ergy of approximately 800 J at the point of entry. That is why,
in this study, the bigger calibre showed exits of the bullets from
the skulls. However, it remains unclear how much energy was
actually transferred to the brain and how much energy was lost
through the exit of the bullet.
It has to be considered that an exceedance of the shooting
distance of 15 m leads to a higher loss of energy which can
cause an inefficient stunning effect. In this case, an adjust-
ment of the calibre to the distance has to be carried out. The
shorter the shooting distance, the higher the precision of the
shot, though.
In this study, the type of the projectile (deformation or frag-
menting bullet) did not have any effect on the impact of destruc-
tion of the brain.
In four out of six cases the lateral shots with the calibre
30.06, bionic black resulted in “failed” shots. This means, the
brain was only insufficiently or not at all damaged. In these
cases, the risk of an inadequate stunning would have been very
high. With the calibre .22 Hornet three out of four lateral shots
proved to be insufficient. Both calibres showed that a precise
lateral shot that penetrates and damages the brain is much
harder to achieve than using a frontal shot. The aiming at the
lateral optimal point of entry is more difficult than aiming at
the intersection point of eyes and horn attachment. Addition-
ally, the anatomy of the brain provides, laterally seen, a rather
flat shaped surface compared to the frontal view.
The additional examinations with the living cattle con-
firmed the results from the foregoing investigations. When
the brain was hit properly, an efficient stunning effect could
be demonstrated. The dissection of the skulls showed reliable
and irreversible damage of the brain tissue displayed as mas-
sive vessel ruptures and contrecoup-bleeding (bleeding in the
caudal area of the brain). In all investigated cases the calibre
30.06 caused an exit of the bullet from the skull. In the cases of
the small bore .22 Magnum, every bullet remained inside the
skulls. If the point of entry was right, no difference between the
two calibres concerning stunning efficiency could be detected.
Conclusion
Stunning via gun shot is an effective instrument in order to
slaughter cattle. The calibres 9.3 x 62, 30.06, .22 Hornet and
.22 Magnum all proved to be fit to inflict an irreversible damage
to the brain if the accuracy of the shot is adequate. However,
the calibres with an energy higher than 400 J and a shooting
distance of 15 m can cause exits of the bullet from the skull.
These stray bullets and fragments can endanger adjacent ani-
mals and men. If bullet fragments enter the carcass they can
cause a decrease in value. Therefore it is beneficial to use a cal-
ibre that provides, proportionate to the shooting distance, the
minimum amount of energy that is recommended for captive
bolts related to race, age, gender and live weight of the cattle.
References
[1] Atkinson, S.; Algers, B. (2007): The development of a stun quality audit
for cattle and pigs at slaughter. In: Animal health, animal welfare and
biosecurity. Aland A (ed.), Proceedings Volume 2, XIII International
congress in animal hygiene, International Society for Animal Hygiene and
Institute of Veterinary Medicine and Animal Sciences: Estonian Universi-
ty of Life Sciences, 17–21 June 2007, Tartu, Estonia, pp. 1023–1027
[2] Atkinson, S.; Algers, B. (2009): Cattle welfare, stun quality and efficiency
in 3 abattoirs using different designs of stun box loading, stun box res-
traint and weapons. Project Report Department of Animal Environment
and Health, Swedish University of Agricultural Sciences (SLU), Skara,
Sweden
[3] Von Wenzlawowicz, M.; von Holleben, K.; Eser, E. (2012): Identifying
reasons for stun failures in slaughterhouses for cattle and pigs in a field
study. Animal Welfare 21, pp. 51–60
[4] Deutsches Bundesministerium der Justiz (BMJ) (2012): Verordnung zum
Schutz von Tieren im Zusammenhang mit der Schlachtung oder Tötung
und zur Durchführung der Verordnung (EG) Nr. 1099/2009 des Rates
(Tierschutz-Schlachtverordnung – TierSchlV)
[5] European Union 2004 Regulation (EC) No 853/2004 of the European par-
liament and of the council of 29 April 2004 laying down specific hygiene
rules for on the hygiene of foodstuffs. Regulation (EC) 853/2004
[6] Deutsches Bundesministerium der Justiz (BMJ) (2007/2011): Verordnung
über Anforderungen an die Hygiene beim Herstellen, Behandeln und
Inverkehrbringen von bestimmten Lebensmitteln tierischen Ursprungs
(Tierische Lebensmittel-Hygieneverordnung – Tier-LMHV)
[7] European Union 2009 Council Regulation (EC) No 1099/2009 of 24
September 2009 on the protection of animals at the time of killing. Regu-
lation (EC) No 1099/2009
[8] AVMA (American Veterinary Medical Association) (2013): AVMA Guide-
lines for the Euthanasia of Animals: Version 2013.0.1. Schaumburg, IL,
USA
[9] Retz, S.K.; Schiffer, K.J.; von Wenzlawowicz, M.; Hensel, O. (2013): Stress-
freie Schlachtung von Weiderindern. Erste Erkenntnisse eines Pilotpro-
jekts. Tierärztliche Umschau 6, S. 242–243
Authors
Dr. agr. Stefanie Retz and M. Sc. Katrin Schiffer are staff members of
the section Agricultural Engineering (head: Prof. Dr. Oliver Hensel) of
the University of Kassel, Witzenhausen. e-mail: sretz@agrar.uni-kassel.de
Dr. vet. med. Martin von Wenzlawowicz is head of the bsi Schwarzen-
bek (applied animal welfare at transport and slaughter – independent
veterinary expertise)
Acknowledgement
This study was financed by the Federal German Office for Agriculture and
Food (Bundesanstalt für Landwirtschaft und Ernährung).
