Why Spay & Neuter?

By Deb Haines

An estimated 5 million to 8 million animals are euthanized in shelters across this country every year. Many organizations are trying to decrease that number by opening low-cost spay/neuter clinics to prevent more litters of puppies needing homes.

Shelter euthanasia is the number one killer of companion animals. Spaying and neutering is the only way to reduce or eliminate that. It’s also better for your pet’s health. And it’s better for you because it will make your life easier if your pet is spayed or neutered.

Small-breed dogs (under 45 pounds projected adult body weight) should be neutered at six months of age or spayed prior to the first heat (five to six months). Large-breed dogs (over 45 pounds projected adult body weight) should be neutered after growth stops, which usually is between 9 and 15 months of age. The decision on when to spay a large-breed female dog is based on many factors—your veterinarian can help narrow down the recommended window of 5 to 15 months depending on your dog’s disease risk and lifestyle.

Shouldn’t I let my dog have a litter before I spay her?

Absolutely not. All the medical evidence suggests a dog should be spayed before her first heat. It’s much easier for her then because it’s a much easier surgery at that time.

  • Spaying your female pet drastically slashes her risk of mammary cancer, which is fatal in about 50% of dogs and 90% of cats.
  • Neutering your male pet eliminates his risk of testicular cancer.
  • Spaying and neutering limits pet overpopulation.
  • Spaying your female pet prevents heat cycles and eliminates yowling, crying, erratic behavior, and bloody vaginal discharge.
  • Neutering your male pet reduces inappropriate behaviors, such as roaming to find a mate, marking inside your home, and fighting with other males.
  • Spaying and neutering is more cost-effective than skipping the surgery. A uterine infection that requires emergency surgery to save your female pet’s life easily can cost several thousand dollars

There is little data concerning the correct age to spay and neuter pets, but emerging research informs AAHA’s guidelines. For example, cancer, orthopedic disease, behavioral problems, endocrine disorders, obesity, and urinary incontinence may be linked to sterilization status and the age at which the procedure is performed.

The decision about when to spay or neuter your pet is one you should make with your

Ref…. https://www.aaha.org/your-pet/pet-owner-education/ask-aaha/spay-or-neuter/

Questions and Answers from PVC veterinarians perspective

  1. Can anyone tell me best time to spay or neuter my dogs?

Dr. Amelie Rivaleau….There is still no hard and fast rule! We are spaying depending on age and size. I tend to recommend spaying any females before or just after the first heat to decrease risk of mammary carcinoma (breast cancer). The bigger dogs I’m ok with waiting until after the first or even second spay for biiiig dogs. But again with every heat we have a measurable increase in risk of developing breast cancer.
Do what’s right for you and ask your primary vet what their recommendations are. Breeders for the most part are almost never sources of reliable information on vet care.

2) What about early spaying ?

Dr. Jacinta Colvin ( AU vet ) …. Don’t panic. There are pros and cons to when you desex dogs and it is usual for the recommendation to be made to spey them before their first heat (usually spey at about 5-6 months) however dogs can be desexed between 3-6 months and shelters will sometimes do them even earlier. Thing is, if you don’t desex a dog until they’re over a year old and you’re sure they’re mature in every way, their chance of getting dog breast cancer becomes much higher, so generally it’s recommended to desex them before maturity to combat this. The other thing that would have played a part in your vet’s recommendation I’d say is the fact that she needed an anaesthetic. Anaesthetics are pretty safe, but they’re not completely risk free, so the less GA’s they need the better and if you can do all the surgery at once you remove the need to anaethetise them again within another month or two. It’s common for vets to recommend trying to get any surgeries required done at the same time in young dogs to prevent multiple anaesthetics being done at this age where possible.

I’ll link you to an article put out by the Australian Veterinary Association: (quote) “It is commonly accepted that desexed females have a greatly reduced incidence of mammary neoplasia. Diseases of the ovaries and uterus are eliminated, however evidence suggests that bitches desexed prior to 20 weeks of age may have a statistically increased incidence of urinary incontinence compared to those desexed later. Testicular tumours in males are eliminated, and there is a reduced incidence of prostate disease, perianal tumours and perineal hernias. There are advantages and risks of early age desexing. Benefits include a faster surgery time, lower anaesthetic dose and faster healing. Recorded side effects include infantile external genitalia, and in dogs, delayed growth plate closure and the potential for associated orthopaedic conditions (including angular limb deformities, hip dysplasia, and cranial cruciate ligament disease).There is a statistically increased risk of urinary incontinence in the bitch if desexed before 20 weeks of age.”


The article from link above ….Ok so before you panic, there are benefits there, and although there are “recorded side effects” that does not mean that your dog WILL get any of these things and desexing at 3 months is definitely not unheard of (I’ve seen plenty of healthy dogs desexed at this age (by both clinics and shelters- shelters in particuluar commonly desex early.) I’d also agree with the article that in my experience, early speys generally have better recoveries as long as they are a good weight at desexing. I’ve seen more than a few due to working at a shelter once upon a time). I’d have your dog on a good brand of puppy food to get the best nutrition for healthy joint development (a good recommendation for regardless of if they are desexed or not while growing.) Urinary incontinence is a possible increased risk when they are older with early desexing (and is the one most commonly mentioned as an increased risk with early desexing), but it can be managed medically if it does occur and if definitely better than dealing with breast cancer. Definitely don’t panic! It’s done now, I’ve seen many dogs out there desexed at that age, and there is a good chance you’ll never see any of the potential risks, and the most common (urinary incontinence at an older age) is manageable if it does occur.

Orthopedic issues are a possibility, but is not something in my experience is super common. (I’d have to check the stats as to what they think the risk actually is, but it’s certainly not like if they’re desexed early I’ll see them for an orthopedic problem, and if they were desexed late I won’t.) There are definitely other factors- genetics are a big one. Other aspects can include diet, growth rate, injuries, fitness etc. You may not see any of the above even if she’s predisposed at the moment. How old is she now? Sometimes hip dysplasia doesn’t present clinically for years if it’s not severe (or may not even be recognised unless the dog is xrayed even if it is there. It’s why breed associations have started hip scoring predisposed breeds to reduce it as what you see clinically, isn’t always what is on the xray.) Unless they’re referring to something else I’m unaware of, cruciate injuries are usually traumatic, so even if the ligaments are a bit weaker than usual, you won’t have a problem unless they do something to injure it. (ie jump and land badly twisting the knee joint.)

3) I have a large breed dog, getting conflicting info on WHEN to get it done. I’ve been told to get it done now, I’ve been told to wait until she’s two years old, etc.

Dr. Iris Eri … There is still a lot of debate in this area. There is a study that looked at Golden Retrievers and how spaying/neutering before one year of age might have increased the risk of cruciate tears and cancers like lymphoma. However, the study only looked at Goldens and was retrospective. It also had a small sample size, but a lot of people take this to heart and decide to wait. And we know that spaying/neutering at VERY young ages like 8 weeks will increase the risk of perineal hernias when older and delay the closure of growth plates, making for very tall dogs.

In my experience, I prefer 6 to 8 mos of age. Spaying before the first heat has been proven to decrease the risk of mammary cancer.

Dr. Deanna Glasgow ….I prefer to wait in these guys, but ideally before a heat. If you are worried about an unwanted pregnancy then I would spay her sooner rather than later.

Dr. Renee Brockett ….Absolutely before the first heat cycle. I recommend no later than 6 months. Dogs that are spayed later after the first heat cycle are at a greater risk of developing mammary cancer which is deadly. There are some recent studies that are breed specific and have small sample sizes which say early sterilization can lead to orthopedic problems. Personally I would rather manage ortho problems than have to euthanize something because of mammary cancer.

Dr. Tessa Fiamengo… Have you spoken with your vet about why they are recommending that time for altering you pet? The truth is there is not a one size fits all answer to this question, which is why you are finding mixed answers. I strongly recommend you sit down with your vet, who knows you and your dog better than random folks on the internet, and talk about the information you have been finding, your ability to manage an estrus bitch and your athletic goals with your pet, ect.

4) We were told to wait until her first heat to promote full growth before doing spay. Our plan is to spay her about a month from now in order to allow the vessels to get back into shape.Is it normal for the swelling to stay after the bleeding itself has stopped?

Dr. Dina Hartzel Wild ….Are you referring to the vulva itself (won’t go down after she’s had a heat cycle) or vaginal hyperplasia protruding from the vulva (will go down after spaying) If the external vulva. It will decrease in size relative to being in active estrus but will not go back to the pre-heat size. Vaginal hyperplasia would appear as smooth, pink tissue protruding from the vulva.


5) When is the best time to neuter ?

Dr. Alexandra Harper …There’s a fair amount of different schools of thought on this issue. I would advise neutering sometime between six months and one year of age for a lab. When to neuter or spay depends on the estimated size of the dog, the smaller the dog the earlier you can spay or neuter (generally speaking, obviously there’s exceptions to everything).

6) Cryptorchidism, The vet told me that I need to neuter him ASAP to avoid cancer among other things. I also heard that for large breeds, male specifically, you should wait until they are a 1 1/2- 2 years. My question is, when is a good time to neuter him? I want him to be healthy and happy. Also will neutering help with his dominance and aggression issues?

Dr. Mike Richards …Neutering MAY help with his behavior. It’s never a guaranteed fix, and definitely doesn’t replace training. As for age of neutering, leaving him intact until a year helps with growth and muscle development, but also increases risk that he will get out and try to mate. In my experience, the advantages of neutering early outweigh the advantages of leaving intact, when it comes to cryptorchidism. I would recommend neutering sooner rather than later. And work with a trainer!

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