What Is The Best Age To Neuter A Collie

Updated July 28, 2022

Whether you call it neuterspaycastrate or desex, the right time to get it done in dogs is a subject of much debate. This is because it varies from breed to breed. Recently, a study was published on the best age for neutering in Collies.

While the paper isn’t perfect (more on that later), it does provide the first evidence for Collies on choosing a time of desexing with the fewest health problems. The study compared dogs neutered at different ages for their rates of:

All of these have been suspected to be linked with the age of neutering. Here’s what they found (only bold values are significant, my summary to follow):

Male < 6 months0/3 (0)0/3 (0)0/3 (0)0/3 (0)
Male 6 – 11 months0/12 (0)0/12 (0)0/12 (0)0/12 (0)
Male 1 year0/3 (0)0/3 (0)0/3 (0)0/3 (0)
Male 2 – 8 years0/7 (0)0/7 (0)0/7 (0)0/7 (0)
Male Intact1/29 (3.45)0/29 (0)1/29 (3.45)2/29 (6.9)
Female < 6 months0/5 (0)0/4 (0)0/5 (0)0/4 (0)
Female 6 – 11 months0/6 (0)1/8 (12.5)0/8 (0)1/7 (14.29)
Female 1 year0/6 (0)0/6 (0)0/6 (0)0/6 (0)
Female 2 – 8 years0/16 (0)0/16 (0)0/16 (0)0/16 (0)
Female Intact0/24 (0)0/24 (0)0/24 (0)0/24 (0)
Joint disorders. For ages 1 through 11 years and for each neuter period: no significant findings.
Male < 6 months0/3 (0)0/3 (0)0/3 (0)1/3 (33.33)1/3 (33.33)
Male 6 – 11 months0/11 (0)0/12 (0)0/12 (0)0/12 (0)0/11 (0)
Male 1 year0/3 (0)0/3 (0)0/3 (0)0/3 (0)0/2 (0)
Male 2 – 8 years1/7 (14.29)0/7 (0)0/7 (0)0/7 (0)1/7 (14.29)
Male Intact2/28 (7.14)0/29 (0)0/29 (0)1/29 (3.45)3/28 (10.71)
Female < 6 months1/5 (20)0/5 (0)1/5 (20)0/5 (0)2/5 (40)
Female 6 – 11 months0/8 (0)0/8 (0)0/8 (0)0/8 (0)0/8 (0)
Female 1 year0/6 (0)0/6 (0)0/6 (0)0/6 (0)0/6 (0)
Female 2 – 8 years0/16 (0)0/16 (0)0/16 (0)1/16 (6.25)1/16 (6.25)
Female Intact0/22 (0)0/24 (0)0/23 (0)0/24 (0)0/22 (0)
Cancers. For ages 1 through 11 years and for each neuter period: no significant findings.

UI was reported in only one of the spayed females.

If this table makes no sense, it’s mostly because there are no abnormal findings. Have a look at this one for Golden retrievers as a comparison. 

Summary: The Best Collie Spay & Neuter Times

There is minimal evidence that Collie health problems are influenced by the age of neutering. Owners of either sex are therefore free to choose the age of desexing that suits them best.

Recommendation: between 6 and 12 months for males and one year for females.

This allows for the general trend of later times with higher body weights. It is older with females as they will come into season at 7-9 months, and we want this to settle down completely before surgery.

This is so far the only science we have for the best desexing age in Collies. Your vet, breeder or online group may have a different opinion based on their experience or personal beliefs. It’s perfectly reasonable to take their advice into consideration as well.

The decision may also be based on other factors such as:

Problems With This Study

In the original paper, the authors appear to make some recommendations based on very limited evidence. I have published the original study data so you can see the actual numbers involved and decide for yourself.

The authors also do not mention the well-known increase in lifespan associated with desexing male and female dogs, which tends to counteract most concerns about specific cancers. The following comment in the paper is a clue that it might also have been true for this population:

Across all breeds the mean age of last entry in the record for neutered males was 5.5 years (range 3.71–6.54), for neutered females 5.7 years (range 4.21–6.97), for intact males 4.9 (range 4.15–7.11), and intact females 4.7 (range 3.41–6.32)

The study tries to also look at the rates of mammary cancer & pyometra in females, but cannot give an accurate assessment for two reasons:

  1. the mean ages listed above are far too young to pick up most cases
  2. pyometra and mammary cancer are rarely referred to university hospitals

Regardless of any concerns, the authors are to be applauded to bringing into focus one of the most common questions from dog owners. For the Collie at least, they’ve made the decision a lot easier.

Related: Best Desexing Age For 35 Breeds | Desexing Choices For Dogs | Costs Of Desexing

Have something to add? Comments (if open) will appear within 24 hours.
By Andrew Spanner BVSc(Hons) MVetStud, a vet in Adelaide, Australia. Meet his team here.

5 Replies to “What Is The Best Age To Neuter A Collie”

  1. You’re recommending neutering between 6 and 12 months for males? That seems awfully young given that most dog breeds will develop their full skeletal structure within 12 to 18 months and their hormones impact that development.

  2. I find it rather useless if they did not follow these collies until their natural end of life.

    We had a beautiful female collie who was desexed at an early age (<6 months) and she developed lymphoma at age 9-10 years. I later learned that spaying early can increase a dog’s risk of developing cancer.

    Needless to say, our new collie pup is now 9 months old and still intact. I was hoping for better information as to when or if to spay her.

    Are there any studies that follow collies throughout their lives?

    1. Hi Beth. I have read the original paper and it seems clear that they did in fact follow these dogs to the end of their life. It was a large retrospective study using many years of clinic data so it should have captured disease at most points in these dogs’ lives after the neutering operation. An additional point is that if you look at the other publications by the same authors, you’ll see that their own personal views appear to be against neutering, so you would not anticipate a bias in the opposite direction.

  3. I beautiful 14 months old boarder collie , with chronic separation disorder. l was advised to leave his sexing until he was a bit older.
    So now if torn whether to desex him or not.
    l live on the Mornington Peninsula.

    Kind Regards
    Paul Wainwright

    1. Hi Paul. If age of desexing has any effect on separation anxiety, it’s likely to be small. Therefore there isn’t a lot riding on your decision. I would follow your behaviourist’s advice.

Comments are closed.