The research I first wrote about in 2021 that offered recommendations on when to spay or neuter 35 dog breeds has expanded to include recommendations for 5 more breeds — German Short/Wirehaired Pointer, Mastiff, Newfoundland, Rhodesian Ridgeback, and Siberian Husky. Let’s take a look at the details for these new breeds.
When to Spay or Neuter Risks
The research looks at the following risks of early spay or neuter in each breed of dog.
- Increased risks of joint disorders, such as hip dysplasia (HD), elbow dysplasia (ED), or cranial cruciate ligament (CCL) tear
- Increased risks of cancers, such as lymphosarcoma (LSA), mast cell tumor (MCT), hemangiosarcoma (HSA), or osteosarcoma (OSA)
- As well as things like mammary cancer, pyometra, and urinary incontinence — in female dogs
Note: “Joint disorder risks are heightened for some larger breeds and for mixed-breed dogs weighing more than 20 kg.”
Of course, there are risks of not spaying or neutering dogs early, namely unwanted / unplanned litters of puppies.
Also, I know a lot of dog people who no longer neuter their male dogs and even some who don’t spay their female dogs at all, but to me the risks are too great not to do it with females. I did, however, wait until my current female dogs were more than 1 year old to spay. In Clover’s case, waiting (and other strategies from our veterinary internal medicine specialist) likely saved her from a lifetime of suffering from constant UTIs (bladder infections).
That said, the risks of never spaying a female dog include the following:
- Risk of life-threatening uterine infection called pyometra
- Unwanted pregnancies and puppies
- Risk of mammary cancer, which is deadly (I have a breeder friend going through this now, and it’s devastating.)
200+ Cases for Each Breed Over 20 Years
Researchers pulled data from the UC Davis veterinary hospital’s records archive and found 200+ cases for each of the 5 breeds. The dogs in these cases all weighed at least 20 kg (44 pounds), and the cases spanned 2000-2020.
Results for German Short/Wirehaired Pointer
The cohort of 443 cases for German Shorthaired Pointer and German Wirehaired Pointer dogs in the study population consisted of …
- 150 intact males
- 89 neutered males
- 90 intact females
- 114 neutered females
Joint Disorders: The big headline is that for female dogs spayed before 6 months of age the rate was “highly elevated,” with 38% having at least one joint disorder. Yikes!
Cancers: For cancer, the important points are that male dogs neutered before 6 months had significantly elevated rates of MCT and HSA, both 8%, over intact male breeds with MCT (2%) and HSA (1%). Females spayed before their first birthday had a significantly increased risk for LSA, 11%.
Mammary Cancer: None of the spayed females developed mammary cancer, but 4% of the intact females did.
Pyometra: None of the spayed females developed pyometra, but 4% of the intact females did.
Urinary Incontinence: Intact female breeds did not develop urinary incontinence, but females spayed before 1 year had an insignificant increase to 6%; male dogs had almost no cases of UI. So, yay, for the boy dogs, I guess.
When to Spay or Neuter German Short/Wirehaired Pointers? “Given the increased rates of both joint disorders and cancers for both male and female dogs with early neutering, the suggested guideline is neutering no earlier than 12 months of age.”
Results for Mastiff
The cohort of 361 cases for Mastiffs in the study population consisted of …
- 148 intact males
- 61 neutered male
- 70 intact females
- 82 neutered females
Joint Disorders: Neutering male Mastiffs dogs before they turned 2 years old “resulted in a significantly elevated risk for a joint disorder, mainly due to CCL.” However, neutering male dogs before their first birthday resulted in a 21% risk of joint disorders and “neutering at 1 year of age was a 15% risk.” The data for spayed female Mastiffs was not statistically significant, but those spayed before 1 year had a 20% risk of a joint disorder.
Cancers: The good news is that spaying female Mastiffs did not result in any elevated cancer risks. However, male Mastiffs “neutered before 1 year had a significantly elevated risk of cancer, 28%.” Yikes!
Pyometra: Intact female Mastiffs had a 12% rate of pyometra.
The paper does not mention mammary cancer or urinary incontinence in the breed summary.
When to Spay or Neuter Mastiffs? “The guideline is to neuter male dogs no earlier than 24 months of age due to joint disorders. With female dogs, it is suggested to neuter no earlier than 12 months of age due to a non-significant elevated incidence of cranial cruciate ligament tear and also due to the large body size.”
Results for Newfoundland
The cohort of 212 cases for Newfoundlands in study population consisted of …
- 74 intact males
- 40 neutered male
- 59 intact females
- 39 neutered females
Joint Disorders: The breed already has high-ish rates of joint disorders, with intact males and females seeing “10% and 7% rates of having at least one joint disorder, respectively.” Neutered male Newfoundlands did not experience significantly elevated joint issues, but “females’ rates for having a joint disorder were significantly elevated: 39% were affected when neutered in the first year.”
Cancers: “There were no cancers in intact female dogs, and only a 3% rate for intact male dogs, with no significant elevations with neutering.” <<That’s really interesting!
Urinary Incontinence: Female dogs spayed before one year of age saw an 18% prevalence of urinary incontinence, but that’s NOT a significant elevation compared to intact female Newfoundlands.
Pyometra & Mammary Cancer: These diagnoses were “rarely recorded.”
When to Spay or Neuter Newfoundlands? “The spaying guideline for female dogs is to neuter no earlier than 12 months of age. Despite no significant data against early neutering, it may be a cautious choice to neuter male dogs no earlier than 12 months of age due to the large body size of the breed.”
Results for Rhodesian Ridgeback
The cohort of 209 cases for Rhodesian Ridgebacks in the study population consisted of …
- 54 intact males
- 69 neutered male
- 30 intact females
- 56 neutered females
Cancers: “Intact male and female dogs had 14% and 13% risk for at least one cancer, respectively. Neutering female dogs before 6 months provided the only significant increase in cancers, with a 25% rate of MCT compared with the 3% rate in intact female dogs.”
Mammary Cancer, Pyometra, & Urinary Incontinence: These things were “were rarely recorded in these female dogs.”
The summary for this breed does not mention joint disorders.
When to Spay or Neuter Rhodesian Ridgebacks? “The guideline is to neuter no earlier than 6 months for male dogs and at least that for female dogs, given their cases of MCT with early neutering.”
Results for Siberian Husky
The cohort of 266 cases for Siberian Huskies in the study population consisted of …
- 64 intact males
- 77 neutered male
- 48 intact females
- 77 neutered females
Joint Disorders: Researchers found “no significant risks” in altered dogs for joint disorders over that of intact dogs. However, female Siberian Huskies spayed before they turn one year old “had a 12% chance of CCL, which would perhaps be significant with a larger dataset.”
Cancers: “Intact male and female [Siberian Huskies] had 10% and 6% risks of at least one cancer, respectively, with no elevation associated with neutering.”
Mammary Cancer & Pyometra: “MC and PYO in intact female dogs were both 2%, but their prevalence in female dogs neutered 2–8 years were 9% and 4%, respectively. However, neither of these results was significant.”
The summary for this breed does not mention urinary incontinence.
When to Spay or Neuter Rhodesian Ridgebacks? “The guideline is to neuter male dogs no earlier than 6 months of age. Given a trend for elevated CCL in early neutered female dogs, it is a cautious choice to neuter female dogs no earlier than 12 months of age.”
Summary Chart – When to Spay or Neuter – 40 Dog Breeds Now Studied
0 comments