Identifying Pain Behaviors in Dairy Cattle

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WCDS Advances in Dairy Technology (2017) Volume 29: 231-239
Identifying Pain Behaviors in Dairy Cattle
Karina Bech Gleerup
University of Copenhagen, Department of Large Animal Sciences, Hojbakkegaard Alle 5,
Taastrup, 2630, Denmark
Email: kbg@sund.ku.dk
 Take Home Messages
 There is nothing in the anatomy and physiology of the cow that suggests
that cows are less sensitive to pain than other mammals.
 Cows in pain are likely to have different behavioural priorities compared to
healthy cows.
 Pain is a serious welfare problem that needs to be addressed to meet
consumer requests in the future. Farmers and veterinarians must address
efficient pain treatment, prevention of pain, and early intervention when
the cow is in pain.
 Too few veterinarians give proper pain relieving treatments, and a major
factor influencing the decision to give pain relieving medicine is the
inability to assess pain in cattle.
 Tooth grinding, vocalizing, head pressing or colic behaviour all indicate
severe pain.
 A pain scoring regime exists; ‘The cow pain scale’ is fast and easy to use
for both veterinarians and farmers.
 Cows will display some signs of pain whenever they are in pain. These
signs are only valuable if someone recognizes them and acts upon them.
Cattle are often described as stoic animals [stoic, from latin ‘stoicus’: “a
person who accepts what happens without complaining or showing emotion”],
which may be the main reason why pain evaluation in cattle is not performed
often enough. There is nothing in the anatomy and physiology of the cow that
suggests that they are less sensitive to pain than other mammals. With the
high prevalence of potentially painful conditions like lameness and mastitis in
dairy herds, pain evaluation should be part of the daily routine; however, that
is not the case. In recent years, scientists from several countries have
investigated factors influencing the decision to use analgesia for cattle. The
studies have been conducted as surveys including veterinarians and farmers.
Certain potentially painful conditions were rated very low; however, only a

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minority of the survey respondents considered cattle unable to experience the
emotional components of pain (Hewson et al., 2007; Kielland et al., 2010).
Veterinarians and farmers generally agreed that cattle suffer from painful
conditions, and that pain relieving treatment is an advantage for the animals.
Despite this overall agreement on painful conditions in cattle, still too few
veterinarians give proper pain relieving treatments and farmers are even more
reluctant to use analgesics (Thomsen et al., 2012). The reasons for this
restricted use of analgesics may be many: economic reasons, practical
reasons, habits and lack of knowledge. As cattle are production animals, drug
regulations are very restricted and complicated, which also influences the
choice of treatment. Another major factor influencing the use of pain relieving
medicine is the inability to assess pain in cattle (Flecknell, 2008). This inability
to assess pain influences the perceived effect of the given pain medication.
This may mean that the initial pain state of the cow is difficult to evaluate, and
also, the improvement of the cow’s pain state may not seem obvious enough.
The lack of a visible benefit of the analgesic treatment will further demotivate
the use of pain relieving drugs in the future. Untreated pain may therefore be
a consequence of poor pain evaluation tools.
 Functions and Effects of Pain
Acute pain is a protective mechanism. People with congenital insensitivity (a
complete lack of pain sensitivity) will experience repeated injuries like self-
mutilation and bone fractures; they have a greatly reduced life expectancy
because they never learn to correlate pain to injury. Pain sense is therefore
essential for maintaining bodily integrity. The emotional and aversive
component of the pain experience promotes the protective motor and learned
avoidance response. It supports convalescence and serves a learning
function for the animal to avoid a similar injury in the future. This does not
mean that cows should not be given pain medication as this does not
completely cut off the pain sensation; rather, it reduces the negative effects of
pain. Treating post-surgical pain in animals reduces weight loss and speeds
up recovery and it is a well-known fact that pain in humans is accompanied by
reduced welfare, poor condition and increased death rate.
When a cow is subjected to pain, it evokes an immediate withdrawal response
and vigorous activity to escape the pain stimulus and to seek protection from
further damage. This is the first line of defence against threats to the integrity
of the body. In the case of trauma, this is followed by behaviours to support
resting the injured area to promote healing. Licking or rubbing near the
painful area can sometimes be seen, as it may soothe pain by segmental
inhibition where signals from one part of the body can help reduce pain in
another part. Animals may take on abnormal postures to avoid or reduce
stimulation of sensitive areas as may be seen in cows with pain standing with
an arched back or lying down only on the non-painful side. Quiescence
promotes convalescence and this may be seen as a change in social

Identifying Pain Behaviors in Dairy Cattle 233
behaviour like isolation from group members, e.g., feeding when it is not so
crowded.
Pain is a dynamic condition, which means that if left untreated or if the animal
is not protected from further stress, pain may increase in magnitude and may
lead to chronic changes in perception of tactile stimuli. This means that a cow
suffering long-term pain may begin to perceive a non-painful normal touch as
being painful.
 Why is Pain Evaluation Important?
There is a growing concern about production animal welfare among various
stakeholders, including the general public (de Graaf et al., 2016). Farmers are
likewise concerned about the welfare of the animals in their care (Von
Keyserlingk et al., 2009). Pain is a serious welfare problem that needs to be
addressed to meet consumer requests in the future. This includes efficient
pain treatment, including prevention of pain and early intervention when a cow
is in pain. Some countries have taken legislative actions towards reducing
pain caused by husbandry procedures, for example, by proposing compulsory
use of local analgesia before a painful event and systemic analgesia after the
painful event. Naturally occurring pain cannot always be prevented and for
this type of pain, early recognition facilitates timely treatment, which increases
the treatment success considerably. Researchers have investigated different
measures for pain in dairy cattle and the duration of lying bouts is one
example of a behaviour that is adjusted to the wellbeing of the animal; the
duration of lying bouts increases when cows are lame. Mastitis also has an
impact on cow behaviour; a recent study found that cows have reduced feed
intake in the days before mastitis was diagnosed and this continued for up to
10 days after antibiotic treatment. The same cows had an increased kicking
rate during milking in the same period (Fogsgaard et al., 2015). The reduced
feed intake and the increased kicking may be pain related and could possibly
be avoided or reduced by adding analgesia to the traditional treatment.
Since animals do not communicate verbally, veterinarians and farmers
include behavioural changes when evaluating cows. Some well recognized
pain manifestations are tooth grinding, vocalizing, head pressing, or rarely,
colic behaviour. These behaviours will most often be noticed in dairy cattle,
but it is important to realize that these are all pain behaviours indicating
severe pain. It is necessary to also be aware of more subtle pain behaviours
to prevent cows with low to moderate pain proceeding to experience
prolonged periods of pain, which becomes difficult to treat and has a poor
prognosis for the future.
Our group evaluated pain behaviours in 2 high yielding Danish dairy herds
(Gleerup et al., 2015) and found that 40 of 100 randomly selected dairy cows
displayed pain behaviours supportive of mild to moderate pain. A thorough

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clinical examination revealed clinical findings indicative of pain in all the
animals, despite the fact that they were supposedly healthy, high-yielding
cows. This is a welfare concern as well as a production concern as pain has a
negative effect on both milk yield and welfare.
 Measuring Pain
Pain cannot easily be measured — not in humans and not in animals. There
is no one good physiological measure for pain. Behavioural changes can
however, be a very important indicator of the presence of pain, as behaviour
reflects the internal state of a human or an animal. Severely lame cows or
cows with other severe diseases may receive extra care and consideration,
whereas cows with mild to moderate cases of clinical disease are more
difficult to detect. The risk of failing to see animals in pain increases as farms
expand and available labour decreases, resulting in less time spent on each
cow. More automated systems are introduced to detect disease and activity
as well as milk yield and milk quality, which can all indicate illness or pain.
These are all very important resources in modern dairy production but direct
animal-based measures may give an earlier warning of pain, and it is
therefore important to keep looking at the animals. Cows will display some
signs of pain whenever they are in pain (Figure 1) but these signs are only
valuable if someone recognizes them and acts upon them.
Figure 1: This photo shows a dairy cow that is in pain and is expressing
it with an abnormal positioning of the hind limbs (in front of each other),
slightly lowered head carriage and a changed facial expression. (Photo
by Karina Bech Gleerup).
The Cow Pain Scale
The cow pain scale (Figure 2) was developed to be quick and easy to use,
making it applicable to every day routines in a busy dairy herd (Gleerup et al.,
2015). The cow pain scale is intended for veterinarians as well as dairy

Identifying Pain Behaviors in Dairy Cattle 235
farmers. Very obvious and well recognized signs of severe pain, like tooth
grinding, vocalization, head pressing or kicking toward the belly are not
included in the pain scale, but these should always be considered alarming
signs of severe pain. The cow pain scale is focused on cows with less
obvious pain behaviours as these are often overlooked. The cow pain scale
consists of 7 behaviours, evaluated from 0-2 and combined into a total pain
score. This pain score is guiding, but if the pain score is above 5, the cow
could be in pain and should be observed and re-evaluated or examined by the
veterinarian.
The 7 behaviours are:
 Attention towards the surroundings — if a cow is in pain, she
tends to be less focused on the environment.
 Head position — pain will often result in lower head carriage. This
behaviour may have several explanations, two of them being an
overall changed posture or avoiding social interaction.
 Ear position — cows in pain keep their ears straight backwards or
very low like lamb’s ears
 Facial expression — the cow has a changed facial expression when
in pain, a so-called pain face.
 Response to approach — a cow in pain is less interested in social
interaction and will therefore try to avoid an approaching person
(described in more detail below).
 Back position — pain in legs or abdomen may result in an arched
back.
 Lameness — lameness is a result of pain in one or several limbs.
Pain in more than one limb may result in a very careful walk, rather
stand a limp.
The first 4 behaviours are evaluated from a distance, while the cow is not yet
alerted to the person observing. Then the cow is approached and the
response to approach is evaluated. When the cow is standing up, the back
position may be evaluated, and finally the lameness is evaluated. Once
accustomed to the scale, this does not take more than about a minute. The
pain scoring is obviously not intended routinely for all animal; rather, it is a
tool for evaluating the cows that are noticed to look different than normal
during the daily round through the barn.

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Figure 2: The Cow Pain Scale. The Cow Pain Scale is modified from the
original version published in “Pain Evaluation of Dairy Cattle”, Appl.
Animal Behavioural Science, 2015, Open Access Pain evaluation in dairy
cattle

Identifying Pain Behaviors in Dairy Cattle 237
The Cow Pain Face
The spontaneous facial expression of pain is believed to be an innate
response, reflecting activity within the pain pathways. Facial expressions of
pain are very difficult to suppress and the use of facial expressions is
therefore considered a reliable and objective measure of pain. Recently, facial
expressions of pain have also been described for several animal species:
mice, rats, rabbits, cats, horses, sheep, lambs and cows. In humans, facial
expressions of pain may be evident even if other pain behaviours are
suppressed. This is very interesting as humans have a specialized neural
apparatus for processing facial cues. This is useful when interacting with
other people, as facial expressions provide important social information, like
mood and level of interest, and it facilitates verbal communication. This may
be useful for evaluating facial expressions in animals too (see Figure 3). It is
well recognized that people working with a particular species for many years
become very skilled at observing different behaviours. If it could be possible
to get better at interpreting these behaviours, this may be a quick and useful
tool for improving welfare and hence production.
Figure 3: The cow pain face. The different changes occurring on the
facial expression of a cow in pain, here pointed out on a cow in pain
following surgery.
Response to Approach
Cows are generally curious animals and gentle contact makes the animals
more likely to approach people resulting in a shorter avoidance distance
(Lensink et al., 2000). When cows are in pain they react differently to an
approaching person. They may avoid contact by keeping their heads low with

238 Bech Gleerup
no eye contact, or they may leave before the person is close (Figures 4a and
4b). This behavioural response is also related to the age of the cow, as a
young heifer may not be as confident with an approaching person as an older
cow may be.
Figure 4a: ‘Response to approach’, score ‘0’. As soon as the cow sees a
person approaching, she is attentive with her head high and ears
forward. This cow is not scared and remains lying, sniffing the hand
(after this, she got up and walked off). A sound cow that is less sociable
with humans will usually remain lying down with a high head and ears
forward until the person approaching is getting near, then she will get
up and walk off in a hurry. (Photo by A. M. Michelsen)
Figure 4b: ‘Response to approach’, score ‘2’. The cow in this photo is
not looking at the person approaching and keeps her ears back. The
cow is not interested in contact, and even when the approaching person
gets close to her head, she does not look. Had the cow been scared, she
would have left but when a cow is in pain, she is not so motivated to get
up, especially if the pain comes from the legs or claws. (Photo by A M
Michelsen)

Identifying Pain Behaviors in Dairy Cattle 239
 Conclusion
Pain evaluation is important to ensure animal welfare in dairy production.
Computer technology can assist with surveillance of the animals but it is
important to use the option of looking directly at the animals as well. This is
useful only if a systematic approach is taken and if there is an action plan if a
cow is found to have a high pain score. It is important to recognize abnormal
behaviours, like pain behaviours, from normal behaviours. This may be even
more difficult in stressed animals, which should further motivate a gentle
handling of the animals to reduce stress to a minimum and to facilitate pain
evaluation.
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