Origin and assessment of bruises in beef cattle at slaughter.
ABSTRACT Studies of bruises, as detected on carcasses at the slaughterhouse, may provide useful information about the traumatic situations the animals endure during the pre-slaughter period. In this paper, we review scientific data on the prevalence, risk factors and estimation of the age of bruises in beef cattle. Risk factors such as animal characteristics, transport conditions, stocking density, livestock auction and handling of the animals are discussed. Investigation of the age of bruises could provide information on when in the meat chain bruises occur and, could help to pinpoint where preventive measures should be taken, from the stage of collecting the animals on the farm until slaughter. We review the methods available to assess the age of the bruises; data on human forensic research are also included. The feasibility to identify traumatic episodes during the pre-slaughter period, in order to improve animal welfare is discussed.
Article: Timing of skin wounds.[show abstract] [hide abstract]
ABSTRACT: Wound examination is indispensable in forensic practice. It is always necessary to determine wound vitality or wound age to correctly evaluate the relationship between death and any wounds. Thus, the determination of wound vitality or wound age is a classic but still modern theme in forensic pathology. Skin wound healing is a primitive but well orchestrated biological phenomena consisting of three sequential phases, inflammation, proliferation, and maturation. Many biological substances are involved in the process of wound repair, and this short and simplified overview of wound healing can be adopted to determine wound vitality or wound age in forensic medicine. With the development of immunohistochemistry and chemical analyses, the scientific field of wound age determination has advanced progressively during recent years. In particular, it has been demonstrated that collagens, cytokines, and growth factors are useful candidates and markers for the determination of wound vitality or age. In this review article, some interesting and instructive results are presented, contributing to the future practice of every forensic pathologist.Legal Medicine 04/2007; 9(2):109-14. · 1.08 Impact Factor
- Australian Journal of Experimental Agriculture - AUST J EXP AGR. 01/1985; 25(2).
- Australian Journal of Experimental Agriculture - AUST J EXP AGR. 01/1987; 27(6).
Animal (2009), 3:5, pp 728–736 & The Animal Consortium 2009
Origin and assessment of bruises in beef cattle at slaughter
A. C. Strappini1,2-, J. H. M. Metz3, C. B. Gallo2and B. Kemp1
1Adaptation Physiology Group, Wageningen University, PO Box 338, 6700 AH, Wageningen, The Netherlands;2Instituto de Ciencia Animal, Facultad de Ciencias
Veterinarias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile;3Farm Technology Group, Wageningen University, PO Box 17, 6700 AA, Wageningen,
(Received 22 May 2008; Accepted 5 January 2009; First published online 16 February 2009)
Studies of bruises, as detected on carcasses at the slaughterhouse, may provide useful information about the traumatic
situations the animals endure during the pre-slaughter period. In this paper, we review scientific data on the prevalence, risk
factors and estimation of the age of bruises in beef cattle. Risk factors such as animal characteristics, transport conditions,
stocking density, livestock auction and handling of the animals are discussed. Investigation of the age of bruises could provide
information on when in the meat chain bruises occur and, could help to pinpoint where preventive measures should be taken,
from the stage of collecting the animals on the farm until slaughter. We review the methods available to assess the age of
the bruises; data on human forensic research are also included. The feasibility to identify traumatic episodes during the
pre-slaughter period, in order to improve animal welfare is discussed.
Keywords: bruise, beef cattle, age of bruises, animal welfare
It is generally accepted that the occurrence of bruises has a
negative impact on animal welfare as well as on the meat
quality of beef cattle.
A bruise – defined as a tissue injury with rupture of
the vascular supply and accumulation of blood and serum
(Hoffman et al., 1998) – develops after the application of
force, usually by a blunt object, sufficient to disrupt blood
vessels (Bariciak et al., 2003). As soon as tissue is damaged, a
region of localized hypersensitivity occurs around the injury
area. The hypersensitivity of the bruised area minimizes
movement of the individual and contact with the injury, until
healing has occurred. Thus, it has been inferred that pain is a
promoter of repair (Basbaum and Woolf, 1999).
Nowadays, concern for animal welfare is a major con-
sideration in meat production in many countries, and is
based on the belief that animals can suffer (Manteca,
1998). Bruising is obviously a source of pain (Gregory, 2004
and 2007). In welfare assessment, pain and the source of
pain should be evaluated where possible, in order to
establish how far the animal’s physical and, also likely,
emotional state is affected and that its welfare is poor
(Broom, 1986 and 1998).
Although bruises are inflicted ante mortem in cattle, they
are not visible in the live animal due to the thickness of
bovine skin and can only be detected post mortem in the
carcasses. It is important to be aware of the possibility
of finding post-mortem artefacts during the evaluation
of bruises. ‘Pseudo-bruises’ that resemble true bruises –
originated by machinery or handling of carcass at the
slaughter line – such as hypostasis, congestion of blood or
post-mortem injuries are artefacts. Artefacts from after
death can lead to misinterpretation and require careful
interpretation (Vanezis, 2001).
Bruising in cattle is not only an indication of poor wel-
fare, it also causes substantial economic losses (Grandin,
2000), since bruised meat is not suitable for human
consumption and must be trimmed off. A carcass that is
bruised may be downgraded or even condemned because it
is less acceptable to consumers. Moreover, a bruised car-
cass decomposes rapidly, since bloody meat is an ideal
medium for bacterial growth (FAO, 2001), having a shorter
Bruises can occur at any point of the meat chain, due
to inappropriate handling of the animal on the farm or at
livestock market, during loading, through road transport
and unloading at the slaughterhouse, penning and even
during stunning procedures (Jarvis et al., 1995). Examples
of potential bruising events are inappropriate handling,
improper use of sticks by handlers, violent impact of the
-Present address: Instituto de Ciencia Animal, Facultad de Ciencias Veter-
inarias, Universidad Austral de Chile, Casilla 567, Campus Isla Teja, Valdivia,
Chile. E-mail: email@example.com
animals against facilities or impact with other animals
(Nanni Costa et al., 2006).
Knowledge on the age of a bruise, combined with infor-
mation on the timing of pre-slaughter events, may facilitate
the identification of the risk factors for bruising and thus
provide information on where animal welfare is suboptimal.
In this paper, we aim to give a state-of-the-art discussion of
the factors and circumstances that cause bruises in beef cattle
in the pre-slaughter period, and to consider potential methods
of age assessment of bruises after slaughter.
Characteristics of bruises
The response of a tissue to a bruise-inducing event depends
on the nature of the mechanical force applied and also on
the anatomical location where the force is applied (Hamdy
et al., 1957b). As a result, bruises may differ in their site,
appearance, extension, shape and severity. Anderson and
Horder (1979) have suggested that in beef cattle, external
factors (i.e. source, transport and handling) may be
responsible for the site where bruises are located in the
body of the animal, whereas animal factors, such as pre-
sence of horns, sex class and temperament, determine the
severity of bruising and may cause deeper lesions.
The assessment of bovine bruises during carcass eva-
luation at the slaughter plant is a retrospective reflection of
all harmful situations endured by beef cattle during pre-
slaughter time. Several bovine carcass scores have been
developed worldwide to be used at slaughterhouses for
commercial purposes. All the scoring systems are based on
visual appraisal of bruise characteristics, such as extent, site
of bruising, colour, appearance and severity, or a combi-
nation of the latter.
Extent and site of bruising area
The Australian Carcass Bruises Scoring System (ACBSS),
devised by Anderson and Horder (1979) classifies the
severity of bruising according to the surface area of the
lesion in three groups: ‘slight’ (S), ‘medium’ (M) and ‘heavy’
(H). A lower-case ‘d’ is used to indicate that the bruising
area comprises deeper tissues, creating three new cate-
gories: Sd, Md and Hd. A diagram is used to record the
site of the bruise where seven areas are distinguished:
butt, rump and loin, rib, forequarter, back, hip and pin. All
the bruises present, whether on the left or right side of the
carcass, are recorded by the same person.
Jarvis et al. (1995) used the ACBSS to quantify the
occurrence of bruises of cattle from two different sources;
they reported that cattle from livestock markets had more
bruises than cattle coming directly from the farm. Further-
more, the researchers using this bruise scoring system
found differences in the distribution of the bruises over the
animal’s body. Compared with animals coming directly from
farms, beef cattle from markets presented more bruises on
the hip (0.33 mean number of bruises per animal v. 0.25;
P,0.05), butt (0.50 bruises per animal v. 0.40; P,0.05)
and back (1.13 v. 0.83; P,0.001).
Although the ACBSS enables carcass bruising to be
recorded reliably and accurately, the records are based on
visual appraisal and according to Anderson and Horder
(1979) the system is not totally consistent between scorers.
Regarding the location of the bruises, Hamdy et al.
(1957b) studied the relationship between the force applied
to inflict a bruise and the type of tissue involved in the
bovine carcass. They observed that the bruises inflicted
over the gluteus, triceps, biceps and trapezius muscles of
the cows were deeper than those inflicted over the lumbo-
dorsal fascia and the serratus muscle. It was concluded
that the degree of bruising depends on the thickness
and density of the affected tissue and its vascularity. No
published studies were found on the relationship between
the site and the characteristics of bruises in the bovine
Colour, appearance and severity
The Finnish Meat Research Institute has developed a car-
cass-bruising evaluation system based on the colour and
severity of the trauma (Honkavaara et al., 2003). Three
categories are used in this system: ‘none’, corresponds to a
clean, non-bruised surface; ‘slight’, denotes a reddish area
with damage on the surface and ‘severe’, means the bruise
is reddish, deep and bleeding damage can be observed
on the surface.
This scoring method may have shortcomings similar to
other methods based on visual appraisal; for example, often
a bruise is barely apparent on the surface even though it
may extend into the underlying tissues.
Deepness and severity
In several South American countries (Argentina, Brazil,
Chile and Uruguay), a bruising grading classification is
currently used which is based on the severity of the bruise
and the tissues affected in the injured area. However, the
use of this grading system is only compulsory in Chile
(Chile, 1992 and 2002). The system identifies bruises as
‘grade 1’, when the damaged area comprises only sub-
cutaneous tissues; as ‘grade 2’, when the lesion affects
subcutaneous and muscular tissue and as ‘grade 3’, severe
bruise, when subcutaneous, muscular tissues and even
bones are damaged (fractures). In Chile, carcasses pre-
senting bruises of grade 2 must be downgraded to a lower
category, and carcasses with bruises of grade 3, to the
lowest category of the carcass grading scale.
Gallo et al. (1999) evaluated the characteristics of cattle
delivered to 22 Chilean slaughterhouses. Their study com-
prised the analysis of official records of 114666 bovine
carcasses. Bruising was evaluated using the grading clas-
sification based on severity of the lesions. The results
revealed that 7.7% of the carcasses had grade 1 bruises,
2.1% had grade 2 bruises and only 0.8% had grade 3
bruises. In contrast to the Australian Bruising Score System,
which records all the bruises present in the carcass, in the
Chilean system if a carcass has multiple bruises, only the
most severe bruise is registered.
Origin and assessment of bruises in beef cattle
Shape and pattern of bruises
A standard protocol for recording bruise patterns might assist
researchers to link the shape of the bruises to their cause
(Grandin, 2000). The cause of bruising can be determined
by the pattern of damage on the carcass, for example, if
severe damage occurs and a large portion of the carcass is
completely bruised, this might indicate that the animal was
trampled in the truck. Grandin (2000) points out that deep
bruises, but small in extent, are most likely caused by horns.
Bruises that consist of parallel red marks are characteristic of
those made by sticks (Weeks et al., 2002).
Although current bruising-scoring systems in the slaugh-
terhouses are useful for learning about the prevalence of
bruises on slaughtered cattle, epidemiological analyses are
required to obtain accurate information on risk factors for
the occurrence of bruises and the likelihood of presumed
Factors affecting the occurrence of bruises
Many factors have to be considered when attempting to
determine the causes of bruises in beef cattle. The following
information is restricted to the characteristics of the animal
itself, transport conditions, way of handling and methods of
Horned v. hornless animals. In the 1970s, it was contended
that horns might be the major cause of carcass bruising in
beef cattle. Meischke et al. (1974) found that the mean
bruised tissue trimmed from carcasses weighted 1.59kg for
horned as compared to 0.77kg for hornless cattle. Some
years later, it was speculated that removing the tips of the
horns could be an effective measure to prevent bruises.
Wythes et al. (1985) subsequently studied the effect of
tipped horns on cattle bruising in Australia. For their study,
the animals were classified into three groups: with entire
horns, tipped horns and hornless animals. The differences
the researchers found between bruising rate in tipped and
un-tipped cattle, whether sent for slaughter as separate
groups or together, were not statistically significant, but
hornless animals had significantly (P,0.05) less bruising
than the tipped and horned animals considered as one
group. The authors concluded that tipping is not an effec-
tive measure to prevent bruising in cattle.
Cattle behaviour. It is known that in bovines, mixing
unfamiliar animals results in more agonistic behaviour,
which gives rise to great stress (McGlone, 1986). Agonistic
behaviour is a conflict situation between two animals and
includes butting, attacking and fighting (Blackshaw et al.,
1987). Butting and mounting among beef cattle can
increase the risk of bruising (Warriss, 1990).
Kenny and Tarrant (1987) observed the response of
young Friesian bulls to social re-grouping and the use of an
overhead-electrified grid to control mounting behaviour.
Mounting was the most common behaviour during social
re-grouping. The researches found that bruising occurrence
was significantly correlated with the number of times an
animal performed mounting (r50.56, P,0.01), was
mounted (r50.44, P<0.05) or was butted (r50.56,
P,0.01). The overhead electric grid was effective to pre-
vent mounting and to decrease bruising.
The relationship between cattle behaviour and its
potential to cause bruising was studied in a large saleyard
by Blackshaw et al. (1987). Butting, attack and fighting
were examined separately. The results showed that the
neck and the flank of the animals were butted by other
animals more often than the hindquarters. The relative
frequency of attack and fights did not differ significantly
between horned and hornless animals. When the animals
were forced to move, they frequently bumped into objects
such as fences, sharp corners, half-opened gates which,
according to Blackshaw et al. (1987), can lead to severe
bruising. The damage ratings of behaviours indicate that
the problem areas at the saleyard were drafting, weighing
and unloading, due to the combination between rough
handling and improper facility design.
More recently, German researchers performed a field
study including the transport of 580 animals (bulls, cows
and heifers) to estimate the impact of facility design on
cattle behaviour and meat quality (von Holleben et al.,
2003). When cattle were not mixed and were driven in
small groups they showed calmer behaviour and fell less
during loading and unloading, resulting in less bruising.
Surprising was the finding that mounting prevention devi-
ces may increase bruising if they are set too low, that is at
20cm above withers or lower.
Age and sex. In the literature, there is some evidence that
the level of bruising also varies with the sex and age of the
cattle (Yeh et al., 1978; Gallo et al., 1999). Jarvis et al.
(1995) quantified the effect of sex class on the occurrence
of the carcass bruising of cattle at two commercial
slaughterhouses in the United Kingdom. Bruise scores were
calculated by multiplying the number of bruises in each size
class (little, slight, medium or heavy) by a weighting factor
(slight 1, medium 3 and heavy 5) and adding these values.
Little bruises (,2cm) were not considered. The bruise
scores were then divided by the number of animals per
group, resulting in a mean bruise score per animal. The
researchers found that when heifers were completely
separated from steers during transport and handling, the
mean number of bruises per animal differed significantly
between sex classes. Heifers had significantly (P,0.001)
more bruises than steers (bruise score 5.40 v. 4.00). This
finding tallies with data obtained earlier by Yeh et al.
(1978), who reported that when kept as separate groups,
cows bruise significantly more than steers and bulls.
Furthermore, only in cows did the amount of bruising
(expressed as weight of bruised tissue trimmed) increase
with increased duration of journey.
Weeks et al. (2002) have pointed out that physical dif-
ferences in fat cover, skin and thickness of hide between
Strappini, Metz, Gallo and Kemp
sexes could affect the susceptibility to bruising resulting
from impacts of similar force. Moreover, on the basis of the
hypothesis that thin animals bruise more easily than fat
animals, Grandin (1998) has suggested that cows have
more bruises due to their lack of fat cover.
The effect of age on bruising was investigated by Wythes
and Shorthose (1991). They found that bruising was
greatest in the heaviest animals – the mature and old cows
and oldest steers of the group. These results support the
earlier findings of Anderson (1973), that older animals have
In Chile it was shown that old cattle are more likely to
pass through a livestock market before arriving at the
slaughterhouse (Strappini et al., 2008), so the fact that old
animals have more bruising may not only be due to age, but
also due to increased handling.
Breed. It has recently been suggested that some differences
in the occurrence of bruises can be attributed to breed
(Minka and Ayo, 2007). In studies carried out in West
Africa, the behavioural activities of cattle during loading
and unloading were assessed in three different Bos indicus
breeds: White Fulani (long horns), Sokoto Gudale (short
horns) and Red Bororo (massive horns). The researchers
found that animals of the Red Bororo breed had the highest
percentage of injuries and the highest score for behavioural
activities. They concluded that this may be related to the
fact that Red Bororo animals have massive horns and are
aggressive by nature. It appears that breed differences can
be attributed to differences in behaviour and to being
horned or hornless.
Significant differences in carcass bruising between breeds
had been reported earlier by Wythes et al. (1985), who found
that carcasses of Zebu crossbreeds had a greater bruise score
compared with British breed animals. However, some years
later, the same authors presented new results. Bruising and
muscle properties of Bos taurus3Bos indicus and Bos taurus
were compared from seven studies. There were no consistent
differences between breeds in bruise score. Based on the
results of these studies, it was concluded that individual
variation in susceptibility to bruising is more important than
genotype differences (Wythes et al., 1989).
This finding agrees with the suggestion of Fordyce et al.
(1985), that differences between individual animals in
susceptibility to bruising and in temperament might be
more important than the variability between breeds.
Distance, time and transport conditions. Road transporta-
tion can be associated with several types of injuries (Minka
and Ayo, 2007). Many authors have emphasized the rela-
tion between distance travelled and occurrence of bruising
in bovines (Yeh et al., 1978; McNally and Warriss, 1996;
Hoffman et al., 1998), suggesting that the level of bruising
might increase with the distance travelled by the animals
and consequently the amount (kg) of bruised tissue trim-
med per carcass (Wythes et al., 1981). However, Tarrant and
Grandin (2000) postulated that the condition under which
the transport takes place is more important than the total
journey time or the distance covered. After the animal has
adapted to the situation, time is a minor problem compared
to loading densities, vehicle design, road conditions or the
driver’s driving behaviour. Previously, Tarrant et al. (1992)
found that 600kg cattle began to lie down after 16h of
transport, but at the highest stocking density of 600kg/m2,
the animals could not rest because of the lack of space.
Although cattle prefer to stand during transport, they do
lie down during long journeys (Knowles, 1999). Thus, pre-
venting animals from resting after 16h or more of transport
may become an important animal welfare issue in many
Studies of the relationship between vehicle design,
transit conditions, climatic conditions, transport time and
distance are required to get a better insight about their
effect on bruising occurrence.
Stocking density. It has been speculated that the extent of
bruising increases with increased stocking density during
Tarrant et al. (1988) transported cattle at three different
stocking densities: low (200kg/m2), medium (300kg/m2)
and high (600kg/m2). Carcass bruising was scored using
the ACBSS. The bruising scores were 3.1 at 200kg/m2,
3.6 at 300kg/m2and 11.9 at 600kg/m2, respectively. From
these results, it was concluded that carcass bruising
increases with increased stocking density.
Cattle transported at high stocking density have limited
room to move and to adopt preferred orientations, such
as to align themselves with the direction of the travel,
which may increase their security of balance. An interesting
observation at high loading density was the ‘domino effect’,
whereby a fallen animal caused others to lose their footing.
Trampling on the floored animal destabilized other mem-
bers of the group and this resulted in more animals going
down. It is likely, that occurrence of the ‘domino effect’ is
related to the driving style, because the majority of inci-
dents in which cattle adjust their position, stumble or fall
are associated with sudden changes such as braking, gear
changes or cornering (Knowles, 1999).
Not only overloading, but also under-loading of trucks
increases bruises. Eldridge and Winfield (1988) transported
animals at three different stocking densities: high (460kg/m2),
medium (345kg/m2) and low (288kg/m2). The Australian
researchers found that carcass bruising was higher in both
the high and low stocking density treatments compared
with the medium treatment.
The contradiction between the findings of Tarrant et al.
(1988) and those of Eldridge and Winfield (1988), in rela-
tion to adverse low stocking densities, may be explained
by the differences in average live weight of the animals
(603 and 400kg, respectively) used in these experiments.
In any way, it is clear that at low stocking densities, loose
animals try to keep their balance in a moving truck and are
more likely to hit the vehicle’s walls and tailgate.
Origin and assessment of bruises in beef cattle
It seems that a solution could be to transport animals in
pens. Honkavaara et al. (2003) carried out several experi-
ments in Finland using vehicles in which there were large
pens (three or four animals per pen) or small pens (one or
two animals per pen). The authors showed that two- and
single-animal pens were optimal to minimize aggressive
behaviour and carcass bruising during transport, presenting
an alternative for transporting animals – especially over
long distances. Unfortunately, the use of movable barriers is
not a common practice in most South American countries
where cattle are transported loose in one compartment, at
high stocking densities (Grandin and Gallo, 2007).
The relationship between stocking densities and bruising
incidence requires further research in order to provide policy
makers with scientific information that can be used to define
national regulations appropriate to the local situation.
Livestock markets, slaughterhouses and handling
In most countries, a high percentage of beef cattle are still
marketed through live auction markets, a process which
extends transport times and multiplies the number of
occasions that animals are loaded, unloaded, driven and
mixed with unfamiliar animals (Knowles, 1999). All of these
conditions are associated with the risk of physical damage
Blackshaw et al. (1987) performed behavioural obser-
vations on about 2400 cattle throughout the livestock
market routine in Australia. It was observed that animals
showed agonistic behaviours during drafting, weighing and
unloading stages, which involve stock handlers moving
animals. McNally and Warriss (1996) found that the pre-
valence of bruising was significantly higher in animals
bought from live auction markets (7.8%) than in those
bought through dealers (6.3%) or direct from farms (4.8%),
suggesting that when animals are handled more, they are
exposed to more potentially traumatic situations.
Weeks et al. (2002) attempted to identify potential
bruising events caused by handling at livestock markets.
They also found that animals that had passed through a
market presented more bruises (71.0% of carcasses, n5
1.095) than cattle delivered by dealers (65.5%, n51.925)
or from farms (53.7%, n51.980). It was concluded that
the more an animal is handled, the greater the chance of
However, other studies indicated that animals sold through
livestock markets did not present more bruises than cattle
sold directly to the abattoirs (Horder et al., 1982).
Cattle transported direct from the farms to the slaughter-
house may be less tired or may find the lairage environment
less familiar than the market cattle (Jarvis et al., 1995).
According to Grandin (1993), if the animals are not tired,
handling can be more difficult, especially if the animals are
excited and therefore subjected to rough and abusive hand-
ling. This corresponds with the finding of Jarvis et al. (1995),
who found significantly greater use of driving instruments
on cattle transported directly from farms than on animals
sold through markets.
Based on the existing evidence, it has been concluded
generally that animals subjected to additional handling and
transport associated with livestock market processes will
present more bruising (Jarvis et al., 1995).
An earlier survey conducted by Marshall (1977) in New
Zealand, reported that bruising was directly related to the
method of handling of cattle. Lensink et al. (2001) inves-
tigated the influence of farmers’ handling of veal calves
during loading, transport and unloading. The authors
found that animals receiving positive contact from the
stockperson are less fearful of people, resulting in fewer
potentially traumatic incidents. Unfortunately, many stock-
persons are not trained to handle animals in a proper way
Cattle can be bruised up until the moment of processing,
furthermore, bruising can occur after stunning and prior to
bleeding (Meischke and Horder, 1976). In relation to the
latter, McCausland and Millar (1982) found that at least
43% of the bruising occurred after the animals arrived
at the Australian slaughterhouses. Nevertheless, it is com-
monly assumed that bruises are inflicted before arriving at
the slaughterhouse, because the probability of developing
bruises in the slaughterhouse is rarely considered. Given
that market cattle have an increased risk of becoming
bruised during transport from and to markets, on arrival at
the slaughterhouse the bruises will be old. But cattle
transported directly from farms have a higher risk to present
fresh bruises because of more handling problems at the
slaughterhouse itself. Therefore, depending on the severity
of abuse during loading and transport or at the slaughter-
house, the comparisons in literature between market cattle
and farm cattle may differ.
It is clear that the way of handling, the use of driving
instruments and the level of exhaustion affect the risk of
bruising in animals passing through markets. More research
should be done on the age of bruises found on carcasses, in
order to elucidate the link between bruise occurrence and
livestock auction and slaughterhouses, so as to pinpoint
where adverse handling has occurred during the period
from loading to slaughterhouse.
Estimating bruise age
In the 1950s, Hamdy and co-workers collected evidence of
biochemical and physical changes in bruised tissues, indi-
cating that the estimation of the age of a bruise allows the
identification of the place and time of livestock damage and
provides information about the causes (Hamdy et al., 1957a
and 1957b). Since then, different methods have been
employed to estimate the age of bruises in animals.
Bruise colour changes
Gracey and Collins (1992) showed that the age of the
bruise can be estimated from its colour appearance in
bovine carcasses; a bright red bruise is likely to be up to
10h old, whereas a dark red bruise is approximately 24h
old. This change in bruise colour is due to the inflammatory
Strappini, Metz, Gallo and Kemp