There is a lot of controversy regarding if and when you should neuter your pets
and although many studies have been performed over the years to determine
the risks versus benefit, the results still seem to be somewhat inconclusive. So in this video,
I'm going to be completely transparent and lay down all the pros and cons of neutering,
backed by scientific evidence, so that you can be a responsible pet owner that can make your
own informed decision. I will not try and force my professional opinion as a veterinarian on anyone,
but will rather present to you both sides of the argument in an easily comparable manner so
that you can be properly educated in order to determine what is best for your beloved pet.
Okay, let's get right into it. Neutering is the process of removing all or part of a dog's
reproductive organs so that they are unable to reproduce. The term "neuter" actually applies
to both sexes, while the term "spay" refers to female and "castrate" to male animals. Neutering
is the most commonly preferred method for sexual sterilization. Most veterinarians recommend that
you should neuter your dog between six and nine months of age. The reasoning behind this is that
at six months of age, pets are fully vaccinated and have matured to the point where they react to
anesthesia and surgery like adults, which reduces the surgical risks substantially. Now let's first
start with the pros of neutering your pet. There's no denial that there's a huge overpopulation
problem with pets all around the world which often results in animals needing to be put down when
shelters are flooded. Multiple studies have found that sexually intact dogs and cats are more likely
to be given up to humane organizations than those who are neutered. This results in an estimated 1.5
million shelter animals being euthanized in the U.S. alone every year, according to the ASPCA. The
two main concerns here are that the majority of the surrendered animals are from unwanted litters
and should sexually intact dogs be adopted, they may reproduce and repopulate those shelters again.
This is mostly at fault of irresponsible pet owners who do not have a sound knowledge of
animal reproduction. Thus, neutering unowned animals is an obvious attempt to maintain proper
pet population control. Behavioral problems, also known as sexually dimorphic behaviors,
is one of the most common reasons why pets are surrendered. These include things like roaming,
mounting and urine spraying. Now "gonadectomy", which is the removal of the testes or the ovaries,
have been correlated with a decrease in the sexually dimorphic behaviors due to
the decrease in the gonadal steroid hormone. Sexual behaviors in male cats, such as roaming,
fighting and urine spraying, for example, makes them extremely undesirable and often unsafe
to be kept as household pets. Castration is therefore beneficial to remove these
behaviors and make them more tolerant for pets owners. One large scale study of over 1 800 dogs
also revealed a decrease in separation anxiety and submissive urination associated with gonadectomy
performed before dogs were five months of age. Mammary gland tumors are the most common tumors of
female dogs and third most common tumors of female cats. They are extremely malignant, which means
they can easily spread to other organs, especially the lungs, which often results in the animal
being put down upon diagnosis. Maintenance of a sexually intact status is a major risk factor
for the development of mammary gland tumors of which the risk increases substantially with age.
One study found that sexually intact dogs and cats have seven times greater risk of
developing mammary gland tumors when they get older compared to spayed dogs and cats.
Pyometra is an infection of the uterus which has the potential to become fatal if left untreated.
It is highly prevalent in all their intact female dogs and cats, but can be treated successfully
with an ovariohysterectomy. BPH is a very common condition in older, sexually intact male dogs
which predisposes them to prostatitis, which is a very painful condition that can lead to
constipation and painful urination. Once again, castration forms an integral part in the treatment
and prevention of BPH in dogs. Testicular tumors are the second most common tumor type in male dogs
and even though they have a low rate of malignancy, castration is curative. Ovarian
and uterine tumors are uncommon in dogs and cats and metastasis is very rare, but once again,
spaying is curative in most situations. Several studies have revealed an increase in lifespan
for gonadectomized animals when compared with that for sexually intact animals. This may be
a reflection of enhanced care of animals by owners who made the investment of surgery, or a decrease
in risk associated behaviors, such as roaming in gonadectomized animals. Now that I've given you
the pros, let's dig into the cons of neutering your pet. As with any surgical procedure,
the immediate concerns of neutering include the usual anesthetic and surgical complications,
such as bleeding, infection and death. These risks are relatively low in routine neutering,
however, they can be increased for some animals due to other pre-existing health factors. It
has been reported that spayed female dogs have an increased risk of developing urinary tract
infections and juvenile or recessed vulvas when spayed before puberty. Male dogs castrated before
puberty had less penile development and male cats had a decreased ability to extrude the penis.
Contrary to popular belief, multiple studies have failed to detect a correlation between gonadectomy
of male cats at any age and a decrease in size of the urethra, which could lead to urethral
obstruction. Other studies, however, did find that male cats at an increased risk of developing lower
urine tract disease. Urinary mechanism sphincter incompetence, also known as estrogen responsive
urinary incontinence, is a common problem in female dogs that have been spayed before three
months of age. This is a multi-factorial problem that is also influenced by breed, body size,
obesity, hormones and the urethral anatomy. Luckily, urinary incontinence can easily be
controlled with medical treatments. Obesity is the most common nutritional disorder of dogs and cats
and gonadectomy is commonly reported to be a risk factor for obesity. Estrogen may act as
a satiety factor which would explain the increase in appetite and concurrent food intake in spayed
bitches. Obesity is also a multi-factorial problem though, and is therefore also influenced by breed,
age, housing, ownership and sex. Timing of the closure of growth plates in long bones
is in part controlled by gonadal hormones in dogs and cats. Gonadectomy at any age before
the closure of these growth plates delays that closure and is associated with the lengthening
of these long bones. Hip dysplasia is a hereditary condition in dogs that affects both sexes,
but it is more prevalent in large and giant breed dogs. One large study revealed that there was an
increase in incidence in hip dysplasia in dogs that was neutered before five months of age.
It is also reported that CCL rupture is more prevalent in gonodectomized male and female dogs
than sexually intact dogs, but it also has a big hereditary component, which is also influenced by
body weight and body condition score. Osteosarcoma is a highly malignant tumor of which the risk of
development increases of age and body weight. One popular study investigated close to 700 purebred
Rottweiler dogs and found that there was a significant increase in incidence of osteosarcoma
in both male and female dogs that had undergone gonadectomy before one year of age. However,
it was also reported that the overall incidence of osteosarcoma within this population of dogs
was much higher than the general population, which does suggest a hereditary component.
Hemangiosarcoma is the most common cardiac tumor in dogs and it has been
reported that gonadectomized animals were at an increased risk of developing both splenic
and cardiac hemangiosarcoma, compared to their intact counterparts. Gonadectomized animals have
a risk of development of TCC of approximately three times that of sexually intact animals.
Gondaectomized dogs have been reported to be on average three times more likely to develop
prostatic cancer compared to sexually intact male dogs. These tumors are also very malignant, often
metastasizing to bones. Some studies have revealed an increased risk of development of Hypothyroidism
for spayed female and castrated male dogs. But Hypothyroidism is easily controlled with medical
management. One study stated that spayed females had an increased risk of developing fatal
pancreatitis as compared with intact females. Another study revealed that the risk of developing
adverse reactions to vaccines is 27 to 38% greater in neutered dogs as compared to intact
dogs. Now Dogtor Pete, how am I supposed to know what is best for my pet, as it seems
to me like the pros and cons seems to take up equal weight in this argument? Well, there's
no one straight answer for all pets and you will therefore need to assess each bit individually.
It really narrows down to choosing the lesser of two evils and basically ends up becoming
a numbers game. Let me give you an example. In this table, adapted from a study in 2007,
the incidence highlights the likelihood that a specific disease or injury will occur in a
population after gonadectomy was performed, and morbidity refers to a condition that is prevalent
in more than one percent of the population and is associated with more than 50% morbidity or
mortality rates. Let's say, for example, you have a two-month-old Labrador Retriever that is not
intended for breeding. This dog will benefit greatly from an ovariohysterectomy performed
before a first estrus as a means of preventing mammary gland tumors, which has a high incidence
and very high mobility rate. Because of a breed, she is also predisposed to CCL injury,
heamangiosarcoma and obesity. Hemangiosarcoma has a very low incidence and obesity can easily
be controlled with good husbandry. This leaves CCL injury as the most important possible detriment.
Because the incidence of CCL rupture is much lower than that of mammary gland tumors and pyometra,
it would make sense to spay the dog and focus on educating yourself on the maintenance of
optimal body condition and management techniques that will minimize the potential for CCL injury.
And to minimize the risk of the development of urinary incontinence, you may want to wait to
perform the spay until the dog is at least 3 months of age, according to these statistics.
This same principle can also be applied to other male and female dogs and cats. Now the truth is,
the results of the majority of these studies are far from definitive and therefore should be
evaluated with a critical eye. The three main reasons for this is as following: Number one,
they are retrospective studies instead of prospective studies. Retrospective studies are
based on previous historic clinical cases which carries the risk of missing important information
from previous medical records. Number two, correlation does not imply causation.
Most of these studies have not definitely proven the results and the claims are therefore only
based on hypotheses. Even though they may have some reasonable and sensible explanations,
the evidence is circumstantial at best. Number three, the statistical methods for establishing
a causal relationship is questionable. Most of these studies use very small sample sizes
which could lead to statistically significant results, even when there isn't one. Also, the way
that these results are calculated is often subject to a built-in selection bias. So in essence,
further research and studies will need to be conducted in statistically significant manners in
order to validate these conclusions. So by now it should be clear that each pet should be considered
as an individual and the benefits and detriments of removing the gonads should be weighed up
against each other. There is no single solution that fits every dog. If you do decide not to
neuture your pet, please understand that you need to fully commit to containing your pets properly,
in order to prevent them from adding to the mass pet overpopulation problem the world is currently
facing. The internet is full of easy to access information and in today's digital age, it can be
very easy to be misled by false exaggerated claims and statements. It is extremely important for you,
as a pet owner, to be proactive, to do your own proper research and therefore to only trust
reliable scientific backed sources. In the end, I know that you only want what is best for your pet
and that is admirable. That is why I created this channel, in order to address difficult topics in
a way that can be a bit more easily understood and consumed. I truly hope that I was of value to you
and that you are now fully equipped to make your own informed decision regarding whether or not
your pet should be neutered. I have linked all the articles that I've mentioned in this video
down in the description below. Please feel free to let me know down in the comments if
you have any questions, or if you would like me to explain something a bit more in depth. Please
give this video a thumbs up, share with your friends and your family and consider subscribing,
as I'll be posting new videos on interesting pet related topics every week. As always,
have a lekker day and I'll see you in another video next week. Cheers!