Spaying – Neutering Cats and Dogs

Early spays and neuters is the sterilization of puppies or kittens at 6 to 14 weeks of age, before they are sexually mature. The traditional age for spaying and neutering is 6 to 7 months of age. The concept of early spay and neuter was developed by humane societies and animal shelters to ensure that their animals are already sterilized before they are adopted out to the public. Early spay and neuter is one technique that is used to combat pet overpopulation, a problem whereby millions of unwanted healthy animals are euthanized each year. The following is some information about early spays and neuters and how it compares to the traditional age of 6 months.

In the past, it became traditional to spay and neuter at 6 to 7 months of age due to various reasons. In the early 1900’s, veterinarians had primitive anesthetics, monitoring equipments, and surgical instruments. Anesthetics were not as safe as they are today, especially for young animals. Veterinarians were mainly men, working with large animals such as horses and cattle. Think of large hands trying to find the tiny uterus in a small dog or cat. The uterus is bigger and much easier to find after the first heat or after having a litter. Therefore, the advice of waiting until after the first estrus or after a litter began.

As the years went by, it was discovered that the incidence of mammary cancer can be reduced by over 96%, if spayed before the first heat. The rate of decreased risk drops significantly after the first heat. Along with better equipment, drugs, and safer surgical techniques, veterinarians began to spay before the first heat. However, determining when the first heat occurs was difficult due to the wide range of breeds and sizes of animals. Since there was such a wide range, six months became the standard, with the goal being to neuter most dogs before their first heat. For cats, the same 6 month standard applied, although some cats come into heat as early as 4 or 5 months of age.

When people began to consider early spays and neuters, there were concerns about increased risk of complications during or after surgery, or increased risk of future behavioural problems. The myth that it was better to allow the dog or cat to have one litter before spaying still existed. Stunted growth, obesity, increased risk of incontinence or urinary obstructions were also concerns.

Research studies have shown that there are no short or long-term negative consequences of performing early spay or neuter when compared to those performed at the traditional age. There is no increased risk of complications, adverse side effects, nor stunted growth. It has also been shown that there is no increased risk of future physical or behavioural problems in animals neutered at early ages than in those neutered at the conventional age.

However, there are special points to consider when performing surgery on very young (pediatric) animals due to their smaller size and increased metabolic rate. For example, they may have an enhanced response to relatively low doses of anesthetics. Young animals should be fasted for no more than 3 to 4 hours before surgery to prevent very low blood sugar levels (hypoglycemia). As for adult surgeries, temperature, heart and respiratory rates must be monitored carefully throughout anesthesia. However, due to a pediatric patient’s decreased ability to maintain body temperature, this is increasingly important. Although pediatric spays and neuters are quick surgeries with minimal bleeding, gentle tissue handling is required due to the delicate nature of the tissues of the young animal. Anesthetic recovery is rapid, meaning they are less groggy and are awake faster than an adult animal after surgery. The veterinarian pays particular attention to these special considerations when performing early spays and neuters.

Most veterinarians still perform spays and neuters at the traditional age of 6 to 7 months because the animal is more physically mature by that age. Kidney and liver function are more efficient at that time, which enables the animal to properly metabolize drugs and anesthetics out of the body. This allows for more predictable responses to medications and decreases the chance of overdose or causing liver or kidney damage. The more mature animal is also better at regulating body temperature to prevent hypothermia during or after surgery.

Most people understand that failure to spay or neuter is the number one cause of too many unwanted cats and dogs. Just one unspayed female cat and her offspring can be responsible for the birth of 73,000 kittens in six years. Many people are surprised to discover that kittens as young as four months of age can copulate and give birth to a litter. Therefore, it is possible that a young kitten can escape from the household and impregnate or become pregnant unexpectedly, contributing to the overpopulation problem.

Early spay and neuter is a useful method for humane organizations and conscientious breeders wishing to ensure that their animals will not contribute to the already overflowing cat and dog population. Some adopters or purchasers claim that they will spay or neuter their pet, but do not actually carry through with it for various reasons. Therefore, early spay and neuter is performed so the animal is already sterilized before they go home with their new owner.

Since there are pros and cons for both options, the decision to have your pet spayed/neutered early or at the traditional age is often based on personal preference. However, the choice should also be based on the physical characteristics and lifestyle of your particular pet. For example, very small breeds (such as a ‘Teacup Yorkshire Terrier’) have such tiny uteruses that it may be best to wait until 6 months of age for the spay to allow the tissues to become larger and easier to handle. On the other hand, a large dog that lives at a breeder’s facility may need to be spayed early to prevent an unwanted pregnancy by the other dogs at the facility. Your veterinarian would be able to recommend the best time to spay/neuter your individual pet based on your pet’s breed, size, and lifestyle.

By Amy Cheung – Pets.ca writer