Spaying and neutering are common procedures performed on dogs for various reasons, including population control, behavior modification, and health benefits. However, recent research has shed light on the importance of timing these procedures to ensure the best outcomes for our furry companions. In this blog, we’ll delve into the current understanding of the optimal timing for spaying and neutering dogs based on scientific evidence, as well as alternative options such as ovary sparing spay and vasectomy.

The Impact of Timing

Traditionally, dogs have been spayed or neutered at a young age, often before reaching sexual maturity. While this approach has been widely practiced to prevent unwanted litters and certain behavioral issues, it’s important to consider the potential health implications associated with early spaying and neutering.

If you opt for a traditional spay or neuter, the age at which this is done is important. Removing the ovaries or testes interrupts the hormonal axis of the sex hormones with the pituitary and other organs. Since gonadectomy prior to puberty or sexual maturity may make the risks of some diseases higher in certain breeds or individuals, the option to leave your pet intact should be available to you. If you opt to remove the gonads (ovaries or testes) the age should be decided in a conversation with you and your veterinarian.

Health Considerations

Several recent studies have suggested a link between early spaying and neutering and an increased risk of certain health issues in dogs. For instance, research indicates that early spaying and neutering may be associated with a higher incidence of orthopedic problems, such as hip dysplasia and cranial cruciate ligament (CCL) injuries. Additionally, there is evidence to suggest that early spaying and neutering may contribute to an elevated risk of certain common cancers, including osteosarcoma and hemangiosarcoma. (Hart et al., 2014). Early spaying may lead to underdevelopment of the vulva, increasing the risk of a recessed vulva.

Hormonal Development: One of the primary concerns with early spaying and neutering is the impact on hormonal development. Hormones play a crucial role in regulating various physiological processes, including bone growth and immune function. Altering the timing of spaying and neutering can disrupt the natural hormonal balance in dogs, potentially leading to long-term health consequences. (Kutzler, 2020).

Behavioral Considerations: In addition to health implications, timing can also influence behavioral outcomes in dogs. Research suggests that delaying spaying and neutering until after sexual maturity may help mitigate certain behavioral issues, such as aggression and anxiety. By allowing dogs to fully mature hormonally, we may better preserve their natural behavioral tendencies and social development. (Starling et al., 2019).

What Spay and Neuter Options Are Available?

Ovariohysterectomy (Traditional Spay):

• Removes ovaries and some of the uterus
• Sex hormones are NOT maintained
• The dog does not have a heat cycle
• The dog cannot get pregnant

Orchiectomy (Traditional Neuter):

• Removes both testes, eliminating testosterone production
• Decreases roaming tendencies and marking behaviors
• Reduces the risk of benign prostatic hyperplasia (BPH) and testicular cancer
• May increase the risk of certain health issues, such as obesity and orthopedic problems, due to altered metabolism and growth plate closure
• Sex hormones are NOT maintained
• Leaves the scrotum unless a scrotal ablation is requested or necessary
• The dog is not fertile and cannot cause pregnancy

Alternative Options: Ovary Sparing Spay and Vasectomy

As alternatives to traditional spaying and neutering, ovary sparing spay (OSS) and vasectomy offer potential benefits for dogs while preserving their reproductive organs.

An ovary sparing spay is where one or both ovaries are left in the abdomen, thus preserving hormonal function, but the uterus and cervix are removed. Because the uterus is removed, the female will not be able to become pregnant, even if a mating occurs. The female will still have heat cycles and be attractive to male dogs. She will have little to no bloody vaginal discharge during her heat cycles. Similarly, vasectomy involves sterilizing male dogs by cutting or blocking the vas deferens while leaving the testes intact.

Ovary Sparing Spay (OSS):

• Benefits:
  • Maintains hormonal function by leaving one or both ovaries intact. This helps in preserving the dog’s natural hormonal balance, which can be beneficial for health and behavior (Zink et al., 2023).
• Disadvantages:
  • Increased risk of mammary cancer with each subsequent heat cycle. Owners can do can perform mammary exams (feeling the chest and abdomen) to monitor for lumps.
  • A pyometra (uterine infection) can develop with intact females or OSS females (stump pyometra)
• Availability and cost may vary depending on veterinary expertise and resources.

Vasectomy:

• Benefits:
  • Preserves testosterone production and associated health benefits, maintaining natural behaviors and physical characteristics while preventing unintended pregnancies (Zink et al., 2023).
  • May be less invasive than traditional neuter surgery, potentially resulting in a quicker recovery time and fewer complications.
• Disadvantages:
  • Does not eliminate behaviors associated with intact males, such as roaming or marking, and may require additional training or management to prevent such behaviors.
  • There is a surgical complication risk for testicular torsion.
  • Risk remains of future benign prostatic hyperplasia (BPH) and testicular cancer.
• Availability and cost may vary depending on veterinary expertise and resources.

Retained Gonads: Health Benefits

Here are some relevant resources and research findings related to the health benefits of ovary spared spay (OSS), vasectomized or intact dogs:

1. Lower Incidence of Cancers: Research indicates that leaving ovaries intact can lead to a lower incidence of certain cancers, including hemangiosarcoma and osteosarcoma. For instance, longer exposure to gonadal hormones was associated with reduced odds of general health problems and certain cancers (Zink et al., 2023).
2. Lower Risk of Transitional Cell Carcinoma: There is evidence suggesting a lower risk of certain cancers, including transitional cell carcinoma, when ovaries are left intact. This aligns with findings that the absence of gonadal hormones can increase the prevalence of some neoplastic disorders (Gazibarič et al., 2022).
3. Lower Incidence of Obesity and Urinary Incontinence: The retention of ovaries can help maintain metabolic rates and reduce the incidence of obesity. Additionally, urinary incontinence is less common in dogs that are not spayed or are spayed later in life (Kutzler, 2020).
4. Lower Incidence of Autoimmune and Orthopedic Conditions: Keeping ovaries intact has been associated with a lower incidence of autoimmune thyroiditis and hypothyroidism, as well as a reduced incidence of orthopedic conditions like cranial cruciate ligament rupture and hip dysplasia (Hart et al., 2016).
5. Increased Lifespan: Studies suggest that females left intact past puberty may experience increased lifespan due to the benefits of retaining their natural hormonal balance (Waters et al., 2011).
6. Behavioral Benefits: Retained ovaries can also result in less aggression towards people and animals, decreased incidence of cognitive dysfunction, and reduced fearfulness and noise phobias. This is attributed to the natural hormonal regulation that occurs in intact dogs (Starling et al., 2019).
7. Delayed Growth Plate Closure and Increased Limb Length: Early spaying has been associated with delayed growth plate closure, resulting in dogs with longer limbs and altered bone structure. A study investigating the effects of prepubertal gonadectomy on skeletal development found that growth plate closure was significantly delayed in neutered dogs compared to sexually intact dogs, leading to greater final radial/ulnar length in both male and female dogs neutered at 7 weeks (Salmeri et al., 1991).
8. Impact on Bone Density and Structure: The study by Salmeri and colleagues also observed that dogs neutered before puberty exhibited lighter bone structure and differences in physical characteristics such as narrower chests and skulls. These anatomical changes were linked to an increased risk of orthopedic conditions (Salmeri et al., 1991).
9. Role of Sex Hormones in Growth Plate Closure: Sex hormones play a crucial role in promoting the closure of growth plates at puberty. The absence of these hormones due to early spaying results in prolonged growth periods and associated structural changes. This hormonal influence on bone development and growth plate closure is well-documented in various studies, highlighting the critical role of sex hormones in achieving peak bone density and proper skeletal development (Hart et al., 2014).

Balancing Risks and Benefits:

When considering alternative options such as ovary sparing spay and vasectomy, pet owners should weigh the potential benefits against the risks and consider their individual dog’s needs and lifestyle. Consulting with a veterinarian experienced in these procedures can help pet owners make informed decisions that prioritize their dog’s health and well-being.

Conclusion:

As our understanding of canine health and behavior continues to evolve, so too do our options for spaying and neutering dogs. By considering factors such as timing, individual health considerations, and alternative procedures like ovary sparing spay and vasectomy, pet owners can make choices that promote the overall well-being and quality of life of their beloved companions. Ultimately, the goal is to provide the best possible care while minimizing risks and maximizing benefits for our furry friends.

Ready to Learn More?

If you have questions about the best approach for your pet, or if you’re unsure about the right decision for your furry friend, Dr. Meghan Barrett is here to help. With expertise in modern veterinary practices and a commitment to your pet’s health and well-being, Dr. Barrett can provide the guidance you need to make informed decisions. Don’t hesitate to reach out and schedule a consultation. Together, we can ensure the best care for your beloved companion.

Contact Dr. Meghan Barrett today and take the first step towards a healthier, happier pet.