For the past three decades,
there has been a trend
toward early spaying and
neutering of dogs for
reasons such as avoiding
unwanted breeding and
reducing some diseases such
as mammary and prostate
cancers. Some people believe
that spaying and neutering
helps to avoid behavioral
problems. The impact has
been dramatic, with an
estimated 85 percent of dogs
in the U.S.1 currently being
spayed or neutered.
Breeders have an important
role in helping puppy buyers
determine at what age to
neuter or spay their dog.
They may require puppy
buyers to neuter or spay
their dog to avoid
indiscriminate breeding,
thus their recommendation is
key in helping owners decide
when to spay or neuter their
German Shepherd Dog.
A retrospective study
evaluating the long-term
effects of spay-neuter
surgeries in German Shepherd
Dogs, published in 2016 in
the journal Veterinary
Medicine and Science,
may change breeders’ views
about the safest age to
recommend the procedure. The
study reported a significant
increase in cranial cruciate
ligament (CCL) tears, or
ruptures, in male and female
German Shepherd Dogs
neutered before 1 year of
age, and it also noted a
significantly higher
incidence of urinary
incontinence in female
German Shepherd Dogs spayed
before 1 year of age.
“I used to recommend
neutering my puppies before
they reached sexual maturity
or at least spaying females
before their first estrous
season,” says Ginny Altman,
of St. Paul, Minnesota,
breeder of Rivaden German
Shepherd Dogs since 1981.
“Now, if the owner wants to
neuter, I recommend waiting
until the dog has matured
and certainly waiting until
they have quit growing,
which is usually between 18
and 24 months of age.”
Altman attributes her change
in perspective to the recent
study in German Shepherd
Dogs. The American German
Shepherd Dog Charitable
Foundation helped to sponsor
the research, which was
funded by the AKC
(American Kennel Club)
Canine Health Foundation.
The research was based on
the veterinary records of
1,170 intact and neutered
German Shepherd Dogs in the
medical database at the
University of
California-Davis Veterinary
Medical Teaching Hospital.
The report examined joint
disorders and cancers
previously associated with
neutering that occurred in
dogs from Jan. 1, 2000, to
June 30, 2014.
The analysis involved a
comparison of disease
incidence in intact dogs
with those neutered before 6
months of age, between 6 and
11 months of age, between 12
and 23 months of age, and
from 24 months through 8
years of age. Three joint
disorders, CCL, hip
dysplasia and elbow
dysplasia, and four cancers,
osteosarcoma, lymphoma,
hemangiosarcoma, and mast
cell tumor, were followed
through 8 years of age.
Mammary cancer in females
was followed through 11
years of age.
Lead investigator Benjamin
L. Hart, DVM, PhD, DACVB,
distinguished professor
emeritus at the University
of California-Davis School
of Veterinary Medicine,
says, “In general, larger
dogs seem much more
adversely affected with
regard to joint disorders by
spaying or neutering, but
there also is breed and
gender specificity. Thus,
the risk-benefit ratio
depends on the severity of
the conditions affected by
neutering, the conditions’
overall prevalence in that
breed, and the degree to
which neutering affects the
risk of those conditions.
One size does not fit all
when it comes to deciding
whether to neuter.”
Dr. Hart, a clinical animal
behaviorist, researches the
behavioral effects of
neutering or spaying in
animals. An ongoing study of
the health effects
associated with spay and
neuter surgery will provide
analyses of a total of 31
breeds for which data has
been compiled. When the work
is completed later this
year, the information will
be available on an
open-access website as a
resource for breeders,
owners, veterinarians, and
researchers.
“Thus far, our findings have
not associated an increase
in diseases due to spaying
or neutering in small
breeds, and in the other
breeds, disease risk was
dependent on gender and
whether spay or neuter
surgery was performed before
or after
1 year of age,” says Dr.
Hart. “There is much
misconception related to the
impact neutering has on an
animal and whether the age
of neutering makes a
difference. We knew we
needed the research to be
breed-specific rather than
generalizing across breeds.”
In one of their
publications, Dr. Hart’s
team compared the long-term
health effects of neutering
in Labrador Retrievers and
Golden Retrievers and
found that neutering before
6 months of age doubled the
incidence of one or more
joint disorders in
Labradors, and increased the
risk in Goldens by four to
five times. Spaying female
Goldens through 8 years of
age increased the rate of at
least one cancer by three to
four times that of intact
females.
Increased Incidence of CCL
Rupture
The decision whether to
neuter or spay a dog often
relates to the dog’s
purpose. A German Shepherd
Dog being campaigned at dog
shows is not eligible for
neutering or spaying because
conformation involves
judging dogs for their
breeding potential. Dogs
that compete in herding
trials, obedience or rally,
agility, tracking, and
Schutzhund may be neutered
or spayed, as these
performance events are
exempt from the breeding
purpose that governs dog
shows. However, owners may
wish to avoid increasing the
risk of a joint disorder
such as hip dysplasia or
CCL, as this could interfere
with performance.
People who buy German
Shepherd Dogs for companions
may want to neuter or spay
their dog to help prevent
unwanted litters, to avoid
bitches coming into season,
and to lessen aggression and
roaming tendencies in males,
though Dr. Hart says
evidence shows that
neutering males after 1 year
is as effective in
controlling aggression as
neutering before 6 months of
age.
Neutering or spaying German
Shepherd Dogs training for
police or military work is
optional. However, it is
important that these dogs be
healthy and fit to do their
jobs, and neutering or
spaying before 6 months of
age could increase the risk
of a debilitating joint
disorder such as hip
dysplasia or CCL.
Among all German Shepherd
Dogs studied, hip dysplasia,
a frequent disease in the
breed, is doubled in risk to
7 to 8 percent by early
spaying or neutering.
However, CCL occurs in less
than 1 percent of intact
dogs but is increased in
risk to 8 to 12 percent with
early spay-neuter surgeries,
resulting in this disease
being the main joint
disorder impacted by early
neutering in German Shepherd
Dogs.
As the most common joint
disorder in spayed or
neutered dogs, CCL rupture
also can shorten a dog’s
working career, is expensive
to treat and requires weeks
of rehabilitation. A
critical stabilizer of the
stifle (knee) joint, the CCL
functions as a rope as it
stabilizes the femur
(thighbone) to the tibia
(shinbone), preventing the
stifle bone from shifting
during activity. Without the
normal CCL stabilization, a
dog’s movement is
compromised and painful
osteoarthritis develops.
In intact male German
Shepherd Dogs, 6.6 percent
were diagnosed with at least
one joint disorder. The main
joint disorder reported was
hip dysplasia, which results
from a loose connection
between the pelvis socket,
or acetabulum, and the
thighbone ball, or femur
head, which creates laxity
in the hip joint.
Degenerative joint disease,
or osteoarthritis, commonly
accompany this disease,
causing pain and disability.
Male German Shepherd Dogs
neutered before 6 months of
age had an incidence rate of
20.8 percent of developing
one joint disorder — three
times greater than in intact
males. In dogs neutered from
6 to 11 months of age, the
incidence was 16.4 percent —
two times greater than in
intact males. Although CCL
rupture occurred in less
than 1 percent of intact
males, in dogs neutered
before 6 months of age and
from 6 to 11 months of age,
the rate increased
significantly to 12.5
percent and 8.3 percent,
respectively.
Similarly, intact female
German Shepherd Dogs showed
an incidence rate of 5.1
percent of having at least
one joint disorder. In
contrast, those spayed
before 6 months of age had
an incidence rate of 12.5
percent — more than double
that of intact females. In
those spayed between 6 to 11
months of age, the rate was
almost 17 percent — three
times higher than in intact
females. CCL, which was
diagnosed in less than 1
percent of intact females,
occurred in 4.6 percent of
females spayed before 6
months of age and in 8.3
percent spayed between 6 and
11 months of age.
Because joint disorders can
be related to body weight,
the researchers also looked
at whether the increased
weight of neutered dogs
could be responsible for CCL
rupture, but they did not
find a connection. Using a
body condition score (BCS)
based on a scale of 1 to 9,
with 5 being ideal, they
compared the body condition
of neutered males with CCL
ruptures to neutered males
without CCL ruptures and
found that the median BCS
for both was 5. The median
BCS for spayed females with
CCL ruptures was 5.75
compared to spayed females
without CCL ruptures having
a BCS of 5.
“We think that early
neutering prevents the
gonadal hormone secretion
that normally stimulates
closure of long-bone growth
plates as a dog approaches
maturity,” Dr. Hart
explains. “The bones grow
slightly longer than normal,
which, in turn, disrupts
joint alignment enough to
lead to clinically apparent
joint problems in some
dogs.”
Elbow dysplasia was
virtually nonexistent in
intact and neutered German
Shepherd Dogs. This
condition is caused by
growth disturbances in the
elbow joint due to a
misalignment of growth
between the two bones in the
foreleg between the radius
(elbow) and ulna (wrist).
A noteworthy finding was
that “dogs of either sex
neutered after 1 year of age
did not have significantly
more joint disorders
compared to intact dogs,”
Dr. Hart says.
Risks Related to Urinary
Incontinence & Cancer
Urinary incontinence is a
disorder mainly affecting
elderly female dogs in which
they involuntarily pass
urine. It is mostly
diagnosed in neutered
large-breed dogs. As
expected, the condition was
not reported in intact
female German Shepherd Dogs,
yet 7 percent of females
spayed before 1 year of age
were incontinent in their
elderly years.
Fortunately, of the cancers
followed in German Shepherd
Dogs through age 8, there
were few reports regardless
whether a dog was intact or
neutered. The research team
cautioned that cancer rates
could increase at later
ages, though they did not
study this.
Mammary cancer was tracked
through 11 years of age
because this type of cancer
characteristically occurs
later in life. About 4 to 5
percent of intact females
and those spayed from 2
through 8 years were
diagnosed with mammary
cancer in contrast to no
cases diagnosed in females
spayed before 6 months of
age.
Spaying has been attributed
to helping to reduce the
risk of mammary cancer,
though a 2012published
study found
neutering provided no
apparent protection against
mammary cancer. Dr. Hart
notes that the protective
factor could be breed
specific. Regardless, in
German Shepherd Dogs, the
incidence of mammary cancer
is fairly low.
A Proactive Preventive
Approach
Given the results of this
study showing the increased
incidence of CCL rupture and
urinary incontinence in
German Shepherd Dogs that
had early spay-neuter
surgeries, breeders should
consider the pros and cons
before deciding the best age
to recommend that puppy
buyers spay or neuter their
dogs. The purpose of a dog
also should be considered in
determining what is best for
a companion dog, a working
police dog, or a show or
sporting competitor could be
different.
A German Shepherd Dog that
is neutered or spayed before
1 year of age and has a CCL
rupture could be out of
commission for months for
surgery and rehabilitation.
Urinary incontinence is an
inconvenient disorder for
owners to deal with because
it requires frequent
cleaning of urine from
floors and bedding. It also
is attributed to dogs being
relinquished to shelters.
The most important finding
in German Shepherd Dogs is
that there is no advantage
of neutering or spaying
before 12 months of age. “I
advise owners of German
Shepherd Dog puppies to be
in no hurry to neuter a male
or spay a female,” Dr. Hart
says. “I always tell them to
wait until their dog is at
least a year old before
neutering.”
Altman believes that Dr.
Hart’s research will help
make it easier to convince
breeders and owners that
early neutering is not the
healthy choice for German
Shepherd Dogs it was once
thought to be. “This study
has been eye-opening for our
breed,” she says. “Waiting
until a dog is 1-year-old to
be neutered or spayed is a
simple way to help prevent
the risk of these
disorders.”
1 Percentage of Dogs That
Are Spayed or Neutered. APPA
National Pet Owners Survey.
American Pet Products
Association: Greenwich, CT.
2017-2018:78.
Purina appreciates the
support of the American
German Shepherd Dog
Charitable Foundation (AGSDCF),
particularly Ginny Altman,
current vice president and
health liaison of the
Foundation, and a past
president and former chair
of the Health and Genetics
Committee of the German
Shepherd Dog Club of
America, in helping to
identify topics for the Purina
Pro Plan German Shepherd Dog
Update newsletter.
The AGSDCF board of
directors also contributes
to helping to identify
topics.
Lead
investigator Dr. Benjamin Hart and other
researchers from the University of
California-Davis published “Neutering of German
Shepherd Dogs: associated joint disorders,
cancers and urinary incontinence” online May 16
ahead of print in Veterinary Medicine and
Science.
