What Is a Dog Neuter or Castration?

eight month old puppy with a cone on his neck protecting him from licking the area where he was neutered
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The term "neuter" is used to describe castration in a dog. It is the surgical removal of a male dog's testicles. A neuter must be performed under general anesthesia by a licensed veterinarian or veterinary student under supervision of a licensed veterinarian. A neuter is sometimes referred to as getting the dog "fixed."

Why Do Dogs Get Neutered?

Dogs are typically neutered to eliminate the possibility of reproduction. Another reason for neutering is to prevent reproductive cancers and to avoid certain behaviors associated with male hormones. Hormone-related behaviors like marking and humping may be prevented or decreased by neutering. In addition, an un-neutered male dog can go to extremes to pursue a female in heat. This can lead to the dog escaping and getting injured or in a fight with another dog.

Puppies are usually neutered around six months of age. Some dogs are neutered earlier. These dogs have not yet reached sexual maturity (puberty.) Neutering eliminates the risk of testicular cancers, and may reduce the risk for prostate cancer, though data is controversial. In some cases, a neutering is done to treat a medical condition related to the testicles or hormones they produce. 

What Are the Risks of a Neuter?

While neutering is considered a routine surgery, the procedure is not without risk. As with any surgical procedure, risks include an adverse reaction to anesthesia, bleeding, bruising, and infection. Fortunately, complications are uncommon.

It's important for a veterinarian to thoroughly examine the dog and perform lab work prior to surgery. The veterinarian can detect health issues that increase risks of complications during and after surgery. 

Overall, the prognosis for a full recovery is excellent in healthy dogs. 

What Happens During a Neuter?

Prior to surgery, the dog is anesthetized. This typically involves a painless injection of an anesthetic drug through an intravenous catheter. Pain medication may be started in advance. Next, a breathing tube is placed in the dog's trachea to maintain an open airway and deliver oxygen mixed with gas anesthesia. The gas percentage is adjusted to maintain the optimum anesthesia level.

Once the dog is anesthetized, monitors that measure the dog's vital parameters (breathing rate, heart rate, blood oxygenation level) are placed. Vital signs are monitored and recorded to ensure the dog is safe during the procedure. Technicians take measures to keep the dog warm because body temperature naturally drops during anesthesia. Intravenous fluids may be administered to maintain blood pressure, prevent dehydration, and offset blood loss during surgery.

Next, the anesthetized dog is placed on his back. A technician shaves the hair above the scrotum (below the penis) and scrubs the skin with a special surgical cleanser that removes dirt and germs. The veterinarian "scrubs in" by thoroughly cleaning their hands, wrists, and forearms with a specialized surgical cleanser. They put on a sterile surgery gown and gloves. To prevent the spread of germs, all staff members in the operating room wear caps to cover their hair and masks to cover their mouths and noses and covers over their shoes.

Before making the first cut, the veterinarian covers the dog with sterile drapes to keep germs and debris from getting into the surgery site. A scalpel is used to make a small incision through the layers of skin and tissue between the scrotum and the penis. Using special surgical instruments, the vet locates the testicular blood supply and spermatic ducts, then skillfully ties them off with suture before the carefully cutting away the testicles. The incision is then closed with layers of internal sutures. Some vets use special skin glue to close the outer layer of skin, Others prefer to use visible external sutures. This is a matter of that vet's preference and the dog's specific needs.

After the surgery is complete, a technician will clean the incision gently and move the dog to recovery. Additional pain medication may be given depending on the dog's needs. The goal is for the dog to wake up in a soft, warm bed with as little pain as possible. 

The entire process from the time anesthesia starts to the time the dogs is awake lasts between 30-60 minutes. The surgery itself typically takes about 10-20 minutes. 

Recovery from Neuter Surgery in Dogs

Most dogs recover quickly after surgery. However, it is important to restrict your dog's activity for about two weeks after surgery. This allows the surgery site to heal properly. Running and jumping can cause internal stitches to tear or cause inflammation that impedes healing.

In addition, it's important to keep your dog from licking the incision. Licking causes irritation and introduces bacteria, both of which can cause infection. For this reason, many vets recommend using an e-collar after surgery. This is the conical collar jokingly called the "cone of shame."

If your vet placed external sutures, these will need to be removed about 10-14 days after surgery. This can be done during a brief visit to your vet's office.

If you suspect your pet is sick, call your vet immediately. For health-related questions, always consult your veterinarian, as they have examined your pet, know the pet's health history, and can make the best recommendations for your pet.