Here is a MAJOR study just published in the Journal of the American Veterinary Medical Association (JAVMA) You can read the whole thing but basically, in a nutshell, it shows that most veterinarians see debarking and earcropping as unnecessary procedures in veterinary medicine and NOW, finally, this study says that declawing should be looked at in the same way! It also says that there is clear evidence of pain
and postoperative complications with declawing.
Hopefully, this will wake up the pro-declaw veterinarians who are performing this inhumane, cruel, and very unnecessary procedure and they will start taking the time to counsel their clients on how bad declawing is for their kitties and how to put in practice the humane alternatives such as scratchers and simple deterrents if there are scratching issues.
162 JAVMA • Vol 248 • No. 2 • January 15, 2016
In ancient Rome, during the First Century CE, Lucius
Columella wrote that it was proper to remove the
tails of puppies to prevent their growth to an “abominable
length” and to prevent madness, which is presumed
to refer to rabies.1 Although the idea that this
procedure could protect dogs against rabies has long
since been abandoned, tail docking is still commonly
performed, both because of a belief that it reduces
the incidence of injuries and because of the resulting
perceived improvements in aesthetics. However,
the effectiveness of this procedure in preventing injuries
has been questioned, and the idea of performing
this and other surgical procedures on animals solely
for cosmetic reasons has been heavily criticized in
many parts of the world.2 In fact, some countries have
passed legislation restricting these types of surgeries.
While anecdotal reports suggest that certain cosmetic
procedures such as ear cropping are in decline in
North America, to our knowledge there are no reliable
estimates on the numbers of these procedures performed
Most surgical procedures performed on dogs and
cats in North America are performed for therapeutic,
diagnostic, or preventive purposes; that is, they are
medically necessary. In contrast, procedures that are
not necessary for maintaining health or that are not
beneficial to the animal can be classified as MUSs. This
would include procedures performed mainly to alter
the appearance of animals (eg, ear cropping and tail
docking in dogs), procedures performed solely to prevent
behaviors that are destructive or annoying (eg,
devocalization and defanging in dogs and onychectomy
in cats), and procedures of dubious or minimal
benefit (eg, dewclaw removal in dogs). Note that elective
neutering of healthy dogs and cats has historically
been performed to prevent or reduce the risk of future
health problems (eg, pyometra, mammary gland
neoplasia, and reproductive tract–related neoplasia)
and to prevent unplanned breeding, which benefits
the population as a whole by reducing the number
of unwanted animals.3 Thus, for the purposes of the
A review of medically unnecessary surgeries
in dogs and cats
Katelyn E. Mills BSC
Marina A. G. von Keyserlingk PhD
Lee Niel PhD
From the Animal Welfare Program, Faculty of Land and Food Systems, University of
British Columbia, Vancouver, BC V6T 1Z6, Canada (Mills, von Keyserlingk); and the
Department of Population Medicine, Ontario Veterinary College, University of Guelph,
Guelph, ON N1G 2W1, Canada (Niel).
Address correspondence to Dr. Niel (firstname.lastname@example.org).
present review, we did not classify elective neutering
of dogs and cats as an MUS, even though there is
evidence that elective neutering, while decreasing the
risk of certain health issues in dogs, may increase the
risk of others.4
MUSs Commonly Performed
on Dogs and Cats
Tail docking (caudectomy) is the surgical removal
of the distal portion of the tail. In the Middle Ages, tail
docking was performed on hunting and fighting dogs
to lessen the risk of injury to the tail5 and is still commonly
performed on dogs of various hunting, working,
and terrier breeds. Tail docking is most often done
within the first week after birth. Typically, a scissors
or scalpel is used to remove the distal portion of the
tail, with 1 or more sutures used to close the resulting
wound. Alternatively, an elasticized band is placed
around the tail, causing loss of tissue circulation and
eventual death and sloughing of the tail.6 According to
1 study,6 tail docking is often carried out by dog breeders
without the use of anesthetics or analgesics. Even
when tail docking is performed by veterinarians, anesthetics
or analgesics may not be used, with 1 study6
finding that only 10% of veterinarians used anesthetics
or analgesics in conjunction with tail docking. Given
that the use of anesthetics and analgesics in veterinary
practice has increased in general since that study was
published,7 it is possible that the percentage of veterinarians
using pain management techniques in conjunction
with tail docking has also increased. However,
good estimates are not available.
Tail docking is sometimes performed in adult dogs
because of tail injury, neoplasia, or self-trauma and in
these instances would be considered a medically necessary
surgery. Note that treatments other than tail
docking have been described for dogs with self-trauma
of the tail, including behavioral modification and
pharmacologic treatment.8 However, the efficacy of
these alternative treatments has not been examined.
One argument in favor of tail docking is that these
breeds require docking to avoid future tail injury.2 To
CVMA Canadian Veterinary Medical Association
MUS Medically unnecessary surgery
JAVMA • Vol 248 • No. 2 • January 15, 2016 163
test this theory, Diesel et al9 completed a case-control
study of tail injuries in working and nonworking
dogs with and without docked tails. Tail injuries that
were reported included fractures, dislocations, lacerations,
contusions, self-trauma, and neoplasia. The
weighted risk of tail injuries in working dogs (0.29%)
was significantly higher than the risk in nonworking
dogs (0.19%), and the risk for dogs with docked tails
(0.03%) was significantly lower than the risk for dogs
without docked tails (0.23%). However, the overall tail
injury rate was quite low, and the authors estimated
that 500 dogs would need to have their tails docked
to prevent 1 tail injury.9 A separate study10 reported
similar results, with a tail injury risk of 0.90% for working
breeds and 0.53% for nonworking breeds, and an
estimate that 232 dogs would need to have their tails
docked to prevent 1 tail injury severe enough to require
treatment by a veterinarian. Recently, Lederer et
al11 examined owner reports of tail injuries in docked
and undocked hunting dogs during the shooting season
in Scotland and found that rates of injuries were
higher in undocked spaniels and undocked dogs of
the hunt, point, and retrieve breeds. The authors also
found that the number of injuries reported for both
docked and undocked hunting dogs was higher than
previously reported for working and nonworking
dogs. For example, 54.7% of undocked spaniels and
20.8% of docked spaniels reportedly had at least 1 injury
during the shooting season. However, only 4.4% of
dogs with a tail injury required veterinary treatment,
suggesting that the risk of serious injury was much
lower than the overall injury estimate. These results
indicate that there may be some minor benefits to tail
docking but likely only in particular breeds of dogs
that are participating in hunting activities.
Notably, a number of dog breeds, including the
Pembroke Welsh Corgi and Australian Shepherd, have
a naturally occurring mutation in the T-box transcription
factor T gene (C189G) that results in a short-tail
phenotype.12 In addition, a few breeds with naturally
occurring short tails do not have this mutation, suggesting
that there are other yet-to-be-discovered genetic
factors affecting tail phenotype. Recently, selective
breeding by outcrossing to a Pembroke Welsh Corgi
with the natural bobtail gene resulted in the birth of
Boxers with naturally short tails.13 Thus, it may be possible
for breeds that traditionally have undergone tail
docking to develop family lines with naturally short
tails. Note, however, that there have been anecdotal
reports that breeding for a bobtail appearance has resulted
in health concerns related to deformed tails and
spinal cord defects. Unfortunately, no scientific literature
is available on this topic, and the extent of this
problem is currently unknown.
Individuals disagree as to whether there is pain
associated with tail docking. When asked about the
degree of pain associated with tail docking in puppies,
82% of dog breeders sampled in Australia indicated
“none” or “mild.”6 In contrast, the majority of
veterinarians (76%) reported the associated pain to
be “significant” or “severe.” In a study14 of 50 puppies
(Doberman Pinschers, Rottweilers, and Bouviers des
Flandres) that underwent tail docking at 3 to 5 days of
age, all puppies vocalized intensely at the time of tail
amputation, indicating that the procedure was indeed
painful. The authors also reported that the puppies
settled down relatively quickly after the procedure,
suggesting that the pain did not last long; however,
puppies were only monitored until they settled, which
took approximately 3 minutes, and further pain behaviors
may have occurred at later time points. Despite
the seemingly short duration of pain, some opponents
of tail docking have argued that any pain is unjust if it
Whether tail docking can result in chronic pain
in dogs has not been extensively studied. Gross and
Carr16 described 5 Cocker Spaniels and a Miniature
Poodle that had extensive self-trauma at the surgical
site for several months up to 1 year after tail amputation
and reported that application of mild pressure to
the affected tail areas elicited a severe pain response.
The pain in these dogs was attributed to neuroma development.
Young female cattle that have undergone
tail docking show increased agitation following application
of hot or cold packs to the tail stub, suggesting
that hypersensitive nerve bundles may be present,17
and up to 80% of human amputees report experiencing
phantom pain following limb amputation.18 Thus,
there is a potential for neuropathic pain in dogs following
tail docking, although whether or how frequently
this occurs is unknown.
Tail docking may also have detrimental effects on
social communication in dogs,19 as research suggests
that social communication in dogs is largely reliant on
body language, with the tail playing an important role.
For example, Leaver and Reimchen19 examined behavioral
responses to dogs with different tail lengths by
placing a remotely controlled life-sized dog replica in
a park. They assessed responses to tails that were short
or long and to tails that were wagging or still. Large
dogs showed more caution approaching the replica
dog when it had a short tail than when it had a long
tail, and the authors speculated that this was a consequence
of failure by the replica dog to signal. Also,
large dogs approached the replica dog with a long, still
tail less frequently than they approached the replica
dog with a long, wagging tail but approached replica
dogs with short, wagging tails and short, still tails
with about equal frequency. In contrast, small dogs
showed greater caution than large dogs, regardless of
tail length or motion, likely because of the height difference
and the small dogs’ inability to view the tail.
Results of this study indicated that social communication
in dogs relies on proper observation of tail signaling,
suggesting that tail docking may impair social
communication in dogs.
Collectively, the available evidence suggests that
tail docking is unnecessary as a routine procedure to
prevent injury, particularly in nonworking companion
dogs; that it causes short-term pain and has the po164
JAVMA • Vol 248 • No. 2 • January 15, 2016
tential to cause long-term neuropathic pain in some
animals; and that it impairs social communication,
which could lead to increased negative interactions
with other dogs.
In dogs, ear cropping involves reshaping the appearance
of the external ear, usually by removing up
to half of the caudal portion of the pinna (auricula).
Following removal of the pinna, the ears are taped and
splinted to facilitate healing in the desired shape. This
procedure is typically performed when puppies are
between 9 and 12 weeks old, after they have received
their initial vaccinations.20 Most often, dogs are anesthetized
during the procedure and may or may not be
given analgesics afterward.
Historically, ear cropping was performed to prevent
ear damage during hunting or fighting, and some
proponents of ear cropping continue to suggest that
cropping is necessary to prevent accidental tearing
of pendulous ears, particularly in hunting dogs. However,
there is no evidence to support these claims, and
many working breeds, such as spaniels and retrievers,
have naturally pendulous ears. It has also been suggested
that ear cropping reduces the risk of ear infection,
as a result of less trapping of moisture and debris
in the ear canal.21 While there is some evidence to suggest
that dogs with pendulous ears have a higher risk
of otitis externa, compared with dogs with erect ears,
it appears that specific breeds tend to have a higher
predisposition than others regardless of ear conformation.
22,23 For example, 1 study found that otitis externa
is more common in Cocker Spaniels, Poodles, and German
Shepherd Dogs,24 and another found a higher
prevalence in Golden Retrievers and West Highland
White Terriers.23 None of these breeds traditionally
have their ears cropped, and their natural ear position
varies between hanging and erect. At least 1 textbook
on veterinary surgery25 no longer includes detailed information
on ear cropping in dogs because of ethical
concerns associated with the procedure, with the authors
indicating their support for the AVMA position
statement against this procedure.
To the best of our knowledge, there are no published
studies on whether ear cropping results in
acute or chronic pain in dogs, although given the
length of the resulting wound, it is clear that the procedure
results in some level of acute pain. However,
information is lacking on common anesthetic and analgesic
practices for dogs undergoing ear cropping. In
addition, we are not aware of any studies on whether
alterations in ear conformation influence communication
with humans or other dogs.
Importantly, ear cropping is no longer taught at
colleges of veterinary medicine in the United States.
Thus, veterinarians performing this procedure in the
future will largely be self-taught,26 particularly as veterinarians
experienced with this procedure retire.
Some veterinarians have justified performing this
procedure because of concerns that serious complications
and animal welfare issues will arise if the procedure
is done by unqualified individuals who are not
veterinarians and do not have access to appropriate
facilities, anesthetics, and analgesics.26
In dogs, the dewclaws represent the vestigial first
digits of the forelimbs and, occasionally, hind limbs.27
Some breeds, such as the Great Pyrenees, Bauceron,
and Norwegian Lundehund, have double dewclaws on
each of the hind limbs.28 Dewclaw removal is typically
performed within the first few days after birth, usually
without anesthesia or analgesia,29 but it may also be
performed later in life (eg, when the dog is spayed or
neutered).30 Sedation and local anesthesia are recommended
when performing this procedure on young
puppies, and general anesthesia is recommended for
The main argument in support of dewclaw removal
is that it prevents injuries associated with accidental
tearing of the dewclaws.29 While the forelimb
dewclaws are typically attached by bone, the hind
limb dewclaws are often attached only by skin, which,
some have suggested, makes them prone to catching
and tearing. Furthermore, because there is no wear of
the associated nail, regular trimming is required to reduce
the chances of the nail being caught. However, to
date, no research is available to determine the actual
incidence of dewclaw tearing, so the true scope of this
problem is unknown.
To our knowledge, the impact of dewclaw removal
on the welfare of dogs has not been researched. As
with any surgery, there is the potential for acute and
chronic pain, but the severity of the pain is unknown.
Declawing (onychectomy) is an elective surgical
procedure that involves removal of the claws
through amputation of all or part of the distal phalanx.
Several variations of the procedure have been
described, including removal of the entire distal phalanx
with a scalpel or surgical laser and removal of
all or most of the distal phalanx with a nail clipper.32
Removal of the distal phalanx with a surgical laser
appears to be the quickest procedure and is associated
with lower levels of postoperative stress and pain
than removal with a scalpel.33 However, it has also
been associated with a higher number of postoperative
complications in the days following the procedure.
33 Transection of the tendons of the deep flexor
muscle (ie, tendonectomy) is sometimes performed
as an alternative to onychectomy, as it prevents extension
of the claws and results in fewer signs of
pain.34 Both onychectomy and tendonectomy should
be performed only by veterinarians with appropriate
anesthesia and postoperative analgesia.
Declawing is usually performed to prevent
scratching-related injuries to people and damage to
property. Recent surveys35,36 of veterinarians indicate
that aggression and property destruction due to
JAVMA • Vol 248 • No. 2 • January 15, 2016 165
scratching are frequent behavior problems reported
by cat owners. Scratching of people and other animals
is undesirable because of the potential for injury and
infection, particularly in people who are immunocompromised.
In some cases, this scratching may be
intentional and related to aggression, but in others it
is unintentional during play and handling. There appears
to be a relatively high prevalence of aggression
in owned cats, with recent research suggesting 36%
of cats display aggression toward their owners37 and
almost 50% of cats display aggression toward either
familiar or unfamiliar people.38 However, although declawing
will prevent scratching-related injuries, it is
unlikely to resolve the problem of aggression in general
owing to the potential for cats to bite as an alternative
to scratching. More research is needed to identify
means to prevent aggression-related behaviors by cats
toward their owners.
Scratching items in the environment is a normal
behavior that serves a number of functions for cats,
including territorial marking and nail conditioning.39
Farm cats have been reported to scratch between 1
and 6 times a day. Scratching behavior is driven almost
entirely by the presence of conspecifics39 but is still
present in cats housed singly in homes. Although it is a
normal behavior, environmental scratching is generally
deemed to be undesirable by owners because it can
lead to property damage. While recent estimates of the
prevalence of environmental scratching are unavailable,
2 older studies40,41 suggest that 15% to 25% of
cats show inappropriate scratching of property, with
one of these studies40 indicating that scratching might
increase the risk of cat relinquishment. Although declawing
is 1 method of preventing scratching damage,
there are alternative methods that do not involve
surgery. For example, owners can provide appropriate
outlets for scratching and trim their cats’ nails regularly.
Therefore, when this procedure is requested, every
effort should be made to educate and assist owners of
cats to pursue possible alternatives that could alleviate
the need for surgery.
The National Council for Pet Population has estimated
that approximately 14.4 million of the 59 million
cats in the United States are declawed.42 Similarly,
a recent study43 reported that 20% of cats admitted
in the Raleigh, NC, area had undergone declawing
or, more specifically, onychectomy. Interestingly, the
percentage of cats that are declawed has apparently
not changed in the past decade despite the growing
controversy surrounding the procedure.43 In a survey
conducted by Yeon et al,34 cats reportedly continued
to make scratching movements following declawing,
but 91% of owners surveyed had an overall positive
attitude about the procedure, whether onychectomy
Various studies44–47 have demonstrated that onychectomy
causes postoperative pain in cats. For example,
Carroll et al44 examined postoperative pain in cats
receiving either butorphanol or no analgesia following
onychectomy and found that in comparison to control
cats, butorphanol-treated cats had higher analgesia
scores during the first 24 hours after surgery. Furthermore,
according to owner reports, butorphanol-treated
cats were more likely to eat and act normally and to
have lower lameness scores during the first day after
discharge. Cloutier et al45 found that even when cats
were treated with butorphanol before surgery, they
had evidence of postoperative pain, as determined by
comparison with control cats that underwent a sham
procedure. Both of these studies involved removal of
the distal phalanx with a scalpel or clipper, but recent
studies assessing the effect of laser removal suggest
that this procedure also results in postoperative pain,
although to a lesser degree than that associated with
other methods. Clark et al46 found that cats that underwent
laser onychectomy were less reluctant to jump
after surgery than were cats in which onychectomy
was performed with a scalpel or clipper. Similarly,
Holmberg and Brisson47 compared pain scores during
the 10 days following onychectomy with either
a scalpel or a laser and found that both groups had
elevated pain scores during the first 9 days but that
the mean score over the first 7 days was higher for the
scalpel group, compared with the laser group. Finally,
Robinson et al33 assessed limb function by measuring
ground reaction forces following laser or scalpel
onychectomy and found that forces were reduced in
both groups following surgery, but the reduction was
greater in the scalpel group.
Researchers have also studied the pain associated
with tendonectomy versus onychectomy, but differences
between the procedures are unclear. While
1 study48 found that tendonectomy resulted in lower
pain scores, compared with onychectomy, during the
first 24 hours after surgery, another study45 found no
differences in pain scores when comparing the 2 procedures.
Jankowski et al48 reported differences in postoperative
complications associated with the 2 procedures.
Of 18 cats that underwent onychectomy, 1 had
severe postoperative pain and another had long-term
lameness. Of 20 cats that underwent tendonectomy,
1 had long-term lameness, but owners of 6 cats expressed
dissatisfaction with the procedure because of
continued scratching and issues with claw growth and
Although both onychectomy and tendonectomy
have the potential to cause acute postoperative pain,
it is likely that a multimodal analgesic approach will
provide adequate pain control. Although a review of
all studies assessing efficacy of analgesic regimens for
control of postoperative pain following onychectomy
and tendonectomy is beyond the scope of the current
discussion, we encourage future research to determine
which analgesic regimes are commonly used
in current veterinary practice and whether they are
A number of studies have assessed short-term
and long-term postoperative complication rates following
onychectomy. Short-term postoperative complications
following onychectomy include pain and
166 JAVMA • Vol 248 • No. 2 • January 15, 2016
associated lameness, hemorrhage, swelling, infection,
and changes in behavior.48,49 Pollari and Bonnett50
examined the risk of postoperative complications
when onychectomy was performed alone or in combination
with other surgeries and reported that cats
that underwent onychectomy in combination with
ovariohysterectomy or castration were more likely
to have postoperative complications than were cats
that underwent either procedure alone. This was particularly
concerning because 53% of cats underwent
One common long-term complication of onychectomy
is claw regrowth, with rates reportedly
ranging from 3.4% to 15.4%, depending on the study
and the method of claw removal.46,48,49 One study46
found that claw regrowth was more common with use
of a nail clipper than with use of a scalpel or laser
(15.4% vs 6.5% and 3.4%). Other long-term complications
include persistent lameness and signs of chronic
pain.46,48,49 Clark et al46 reported the highest rates of
pain-related complications, with up to 23% of cats
having ongoing lameness and 42.3% of cats showing
signs of pain on paw palpation. Owners have also reported
long-term behavioral changes in cats following
onychectomy such as house soiling and an increased
resistance to allowing the paws to be handled or an increased
incidence or severity of biting, compared with
behavior before the procedure.51
Alternatives to declawing include regular nail
trimming and use of artificial nail caps to minimize
property damage and provision of appropriate
scratching surfaces such as scratching posts and substrates.
52 A study53 of 128 Italian cat owners found that
sexually intact male cats were more likely to scratch
other surfaces when a scratching post was absent
from the environment, and Cozzi et al39 reported that
a feline interdigital semiochemical, a cat pheromone
replacement made of fatty acids, can be used to control
excess behavioral scratching through placement
of this substance on a desired scratching location.
Behavior modification methods may also decrease environmental
scratching. Given clear evidence of pain
and postoperative complications with declawing, this
procedure should be considered as a last resort after
all other behavior modifying measures have been attempted
and when the only other alternative is relinquishment
In dogs, devocalization (ventriculocordectomy)
involves complete or partial removal of the vocal folds
to prevent vocalization or reduce the intensity of vocalizations
that are produced. The procedure can be
done through an oral approach or by means of a laryngotomy.
Anecdotally, the oral approach appears to
be more commonly used in clinical practice, although
laryngotomy is the recommended approach.54 Devocalization
procedures vary in effectiveness, with great
variation among breeds.54 In particularly excitable
dogs, increased airflow through the larynx following
devocalization can result in the ability to bark to some
degree.54 As a result, some owners administer tranquilizers
Excessive barking is seen as an undesirable behavior
by owners and others affected by the barking and
reportedly increases the risk of relinquishment.55,56
One study56 found that excessive barking accounts
for 11.3% of reported undesirable behaviors in dogs.
Alternatives to devocalization are typically aimed at
addressing the underlying cause of the undesirable
barking. Common causes of undersirable barking include
general anxiety, separation anxiety, and compulsive
disorders,57 and treatment by means of behavior
modification with or without adjunctive medication
should be attempted first. One study58 found that
positive reinforcement training was effective at reducing
barking in response to someone knocking at the
door, and dogs that are exercised more frequently are
found to bark less than dogs that are not exercised.59
While there appears to be general agreement within
the veterinary behavior community that positive reinforcement
is the most appropriate training method
for dogs, barking is often treated through the use of
methods that incorporate positive punishment. Both
electric shock and citronella spray collars have been
found to reduce the incidence of certain types of barking.
60,61 However, the effectiveness of citronella spray
collars is decreased when the collar is worn continuously,
and a rebound effect (increased barking) is
frequently observed after the collar is removed.60 In
addition, there are concerns that electric shock and
citronella spray collars may cause fear and pain in
dogs. One study61 found no difference in serum cortisol
concentrations between dogs wearing electric
shock or citronella spray collars and control dogs.
However, another study62 found behavioral signs of
fear and stress in dogs in response to use of an electric
shock collar, including lowered posture, vocalizations,
oral behaviors, and aggression toward the handler.62
In addition, when used improperly, electric shock collars
can lead to burns and infections. Finally, in dogs
with excessive barking, devocalization only removes
the manifestation of the problem (ie, the dog is no
longer being able to bark) and does not address the
underlying behavioral problem, which may be negatively
affecting the dog’s quality of life. Thus, in dogs
with excessive barking, the underlying cause should
be identified and addressed before devocalization is
A potential long-term complication of devocalization
in dogs is formation of a laryngeal web that obstructs
airflow63 and may require corrective surgery.31
Laryngeal web formation occurs more commonly after
devocalization through an oral approach, with clinical
signs developing between 3 months and 3 years
after surgery in 1 report.63
Defanging involves removal or reduction of the
canine teeth and can be performed in either puppies
or adult dogs. Although this procedure should only be
performed with appropriate dental techniques, it is,
JAVMA • Vol 248 • No. 2 • January 15, 2016 167
in some cases, performed by cutting or breaking the
teeth near the gingival margin and may or may not
involve adequate anesthesia and analgesia.64
Defanging was originally developed to decrease
the danger captive wild animals posed to humans,
and similar justifications have been presented by advocates
of this procedure in companion animals.65
Although aggression can be a serious concern in certain
dogs, this procedure is not fully effective at reducing
the risks of biting injuries. Appropriate treatment
of aggression should involve risk management and
treatment to reduce the behavior problem. Although
research has not been conducted on pain and behavioral
effects of defanging in companion animals, this
procedure is considered unnecessary when trying
to prevent human-animal conflicts with exotic carnivores
and similar results can be predicted for companion
Legislation Related to MUSs
Some of the earliest legislation restricting MUSs
in dogs and cats was passed in the European Union
in 1987, when the European Convention for the Protection
of Pet Animals was implemented. This treaty
prohibits any “surgical operation for the purpose of
modifying [the] appearance of a pet animal or for
other non-curative purposes,”66 which would include
tail docking, ear cropping, devocalization, declawing,
and defanging. Veterinarians can make exceptions
to these prohibitions if the procedure is considered
necessary for curative reasons or the benefit of a particular
animal, or to prevent reproduction.66 However,
regardless of the reason, all surgical operations must
be carried out by a veterinarian and under anesthesia
if the animal is believed to be in, or have the possibility
of being in, severe pain.66 Although this convention
was initially ratified by 4 member states in 1992, it is
noteworthy that as of 2014 some members of the EU
had yet to ratify it. In some of the countries that have
not yet ratified the convention, alternative legislation
restricts at least some of these procedures. For example,
in the United Kingdom and the Netherlands, ear
cropping, tail docking, and declawing are restricted. In
addition, some countries, such as France, have ratified
the convention but excluded tail docking from the list
of prohibited procedures.67
Many additional countries have incorporated
MUSs into their animal welfare legislation, but recommendations
vary by country. For example, declawing,
ear cropping, and tail docking are restricted
in Australia and Israel; declawing, devocalization,
and ear cropping are restricted in New Zealand; and
tail docking and ear cropping are restricted in Brazil.
We are not aware of legislation in any countries
that restricts surgical removal of the dewclaws in
Current Status in North America
Both the CVMA and AVMA have a number of position
statements regarding MUSs. For instance, the
AVMA position statement on tail docking and ear
cropping states that it “opposes ear cropping and tail
docking of dogs when done solely for cosmetic purposes.”
68 The AVMA has also produced comprehensive
literature reviews and fact sheets to support these
position statements. The CVMA has taken a stronger
stance by indicating that the organization “opposes
the alteration of any animal by surgical or other invasive
methods for cosmetic or competitive purposes,”
which includes tail docking and ear cropping in dogs
as well as cosmetic dentistry, tattooing, and piercing.69
Although these position statements are decidedly
against MUSs, they are ultimately only suggestions because
these organizations have no enforcement capabilities.
Indeed, veterinarians practicing in Canada
and the United States are still able to perform these
procedures at their own discretion, with a few exceptions.
In addition, anecdotal reports suggest that some
procedures, most notably tail docking, are performed
by breeders without the assistance of a veterinarian.
It has been suggested that some veterinarians elect to
continue tail docking puppies in fear that failure to do
so will result in less qualified people, such as breeders,
undertaking the procedure without access to proper
medical facilities and appropriate analgesics.2 This
concern is supported by a study6 that found 51% of
the breeders that were surveyed were performing the
procedure on their own.
The CVMA position statement on cosmetic alterations
also states that the association “strongly
encourage breed associations to change the breed
standards” in the hopes that the number of dogs
that are ear cropped and tail docked will decrease.69
Breed standards in Canada and the United States
have changed to allow showing of dogs that have not
undergone ear cropping or tail docking. This is likely
to have reduced the number of dogs undergoing
these procedures, but relevant figures are not available.
Although the Canadian Kennel Club and American
Kennel Club do not encourage these procedures,
they also do not specifically discourage them. The
American Kennel Club, for instance, states that it
endorses “acceptable practices integral to defining
and preserving breed character and enhancing good
The CVMA and AVMA also have position statements
against MUSs used primarily for behavioral
modification, including declawing, devocalization, and
removal or reduction of the teeth.52,69,71,72 For example,
the CVMA position statement on onychectomy
of domestic cats states that the association “strongly
discourages onychectomy of domestic cats for routine
purposes” as it “prevents cats from expressing normal
behaviors and causes pain.”52 The AVMA position
statement echoes this message and encourages client
education and other preventive measures be taken before
declawing is considered. Similar suggestions for
attempts at behavioral modification to prevent the
problem behavior are included in the devocalization
position statements of both the CVMA and AVMA.
However, for each of these position statements there is
168 JAVMA • Vol 248 • No. 2 • January 15, 2016
little guidance as to what attempts at alternative strategies
are sufficient to justify the need for these procedures.
Thus, owners with a lower tolerance for behavioral
problems may elect to pursue them without
first attempting alternative strategies.42 Notably, pursuing
alternative strategies to correct behavior problems
related to scratching, aggression, and barking can
involve substantial time, expertise, and expense, and
owners may not be willing to invest their resources in
alternative strategies when a surgical option is available.
Some have argued that if these procedures were
unavailable, such owners might opt for relinquishment
or euthanasia. However, many veterinary clinics
offer declawing of kittens in conjunction with spaying
or neutering as a preventive measure when scratching
behavior is not yet a concern. Thus, further discussion
among stakeholders to determine how best to balance
these ethical tradeoffs with an aim toward reducing
the number of these procedures being performed is
The role of national veterinary organizations such
as the CVMA and AVMA in reducing the number of
MUSs that are performed should not be underestimated.
In some cases, their position statements have been
incorporated into regulations initiated by provincial
or state regulatory bodies to restrict veterinarians
from performing these surgeries. For instance, restrictions
on veterinarians performing ear cropping and,
in some cases, tail docking have been incorporated
into the bylaws of veterinary organizations in 6 Canadian
provinces (British Columbia, Manitoba, Saskatchewan,
Newfoundland and Labrador, New Brunswick,
and Prince Edward Island).73 However, these restrictions
do not apply to nonveterinarians who may be
performing tail docking and dewclaw removal outside
of a clinic environment. Newfoundland and Labrador
is the only Canadian province that has incorporated
MUSs into formal legislation. In this province, the Animal
Health and Protection Act was passed in 2010,
banning ear cropping in dogs for the purposes of conforming
to breed standards.74 Additionally, this province
has bylaws that prohibit docking of tails in all
animals except when medically necessary.
A number of similar bylaws have been created in
some states within the United States, many of which
are based in principle on the AVMA guidelines. Fourteen
states restrict tail docking in some species; however,
only Maryland and Pennsylvania restrict tail
docking of dogs.75 In Pennsylvania, this restriction is
for unqualified persons performing the procedure after
5 days of age, but veterinarians can perform the
surgery regardless of age.75 Legislation restricting ear
cropping of dogs is the most common in the United
States, with 9 states having restrictions. In the case of
Washington State, ear cropping is permitted when in
line with good husbandry practices.75 After the CVMA
released a position statement in 2009 that “discourages
devocalization of dogs unless it is the only alternative
to euthanasia,” and the AVMA released a similar
statement 4 years later, a law was passed in Massachusetts
that banned this procedure.76 Devocalization is
also prohibited in 4 other US states, unless medically
necessary. In addition to state-level restrictions, municipalities
have in some cases implemented bylaws
restricting MUSs in animals. For example, declawing
is banned in a number of municipalities throughout
While veterinary organizations in North America
have been clear about discouraging various MUSs
through the publication of position statements, their
role to date has been relatively passive. In contrast, the
Australian Veterinary Association actively called for a
ban on tail docking in dogs starting in 2008,77 which
was in part responsible for passage of national legislation
banning this procedure. This legislation ensures
that no persons in Australia, including nonveterinarians,
can perform this procedure. We would suggest
that there may be value in veterinarians in Canada and
the United States taking a similar stance in suggesting
formal legislation as a method of reducing the number
of MUSs in dogs and cats.
Public Attitudes Toward
MUSs in Dogs and Cats
Community consensus regarding right and wrong
governs the actions of society, which then forms
policies and laws.78 Challenges arise when there is
disagreement among stakeholders, preventing a consensus
from being reached. This is the case for many
MUSs, in that stakeholders differ in what they consider
to be acceptable. Given the distributed authority
governing companion animal welfare regulations and
legislation in Canada and the United States, it is not
surprising that leadership comes in large part from
the CVMA and AVMA, in combination with the Canadian
and American kennel clubs and specific breed
associations. Equally disconcerting is that despite the
American Kennel Club stating that unaltered dogs will
not be disqualified when entered into competitions,79
many owners believe that failure to comply with traditional
breed standards will reduce their dogs’ chances
of winning. Some organizations have argued that banning
these procedures is a violation of an individual’s
rights. For example, the United Kingdom–based Council
of Docked Breeds campaigns to protect the owner’s
right to choose tail docking as an option, arguing
that legislating these practices removes a person’s
freedom of choice.80
Social distance is defined as the emotional, psychological,
and physical distance between one individual
and another, typically 2 humans.81 In the past few decades,
the social distance between humans and companion
animals has decreased drastically. This likely
accounts for the change in attitudes regarding what is
acceptable versus unacceptable in relation to animal
treatment, with the effect that practices that were once
seen as being acceptable are now questioned.81 In
some cases, language choice can be used to influence
stakeholders and evoke emotion, a strategy commonly
used by animal rights advocates, who employ words
JAVMA • Vol 248 • No. 2 • January 15, 2016 169
such as oppression, suffering, and cruelty to appeal
to human emotion.82 In other cases, euphemisms can
be used to increase social distance and decrease empathy.
Both the CVMA and AVMA have acknowledged
these potential concerns in their position statements
regarding declawing and devocalization by stating that
owners must be educated with regards to the potential
alternatives, the details of the procedure to be performed,
and the potential risks. However, there are no
data available to determine how often these conversations
between veterinarians and owners occur or what
effect they have on the owner’s willingness to proceed
with the procedure. Further research in this area is
critical to accurately gauge current societal views on
MUSs in dogs and cats.
We strongly believe that in a clinical setting, surgical
procedures should be performed on animals only
if they have or can be expected to have clear benefits
for the animal or the population as a whole. At a minimum,
the procedures discussed in the present review
all cause some degree of acute pain and are associated
with some risk of infection or other adverse effects.
Society’s attitudes toward dogs and cats have changed
over time, likely because of decreased social distance,
with the result that attitudes toward certain procedures
that were once considered acceptable are now
being reconsidered. In many countries, discussions
among broad ranges of stakeholders have resulted in
legislation banning surgical procedures that are considered
elective or unnecessary.
People are willing to acknowledge that animals
experience pain but do not always appear to be willing
to take appropriate action to treat or prevent
that pain.83 This appears to be true in the case of the
procedures discussed in the present review, which
are known to be painful but are still commonly performed.
84 We recommend the following strategies
for enacting change in Canada and the United States
with regards to MUSs in dogs and cats. First, further
research and education are needed on effective methods
for preventing or treating the underlying behavior
problems that traditionally have resulted in declawing,
devocalization, and defanging. Second, further
research on public attitudes toward MUSs is needed;
specifically, understanding the beliefs and values held
by the public must be a priority, as only then will it be
possible to encourage policy and legislation that accurately
reflect the views of current society. Third, veterinarians
should take a leadership role in educating
both owners and the broader public on the important
topic of MUSs in dogs and cats.
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