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Growth questions/first heat

lilliesmomma

Well-Known Member
Lillie just turned 9 months old. I have been told she will grow her height for 2 yrs and her bulk for the next 2 yrs. Is that true. I'm not rushing her growth, I know not to do that. I'm just curious. Also when does a large breed dog go into their first heat cycle? ( usually ). I'm not going to breed her so I have also read that she shouldn't be spayed until she is over a year or it can cause health problems later in life. Have I read it right?
Thanks in advance.
 

Cody

Well-Known Member
Most Molosser breeds fill out until they are 3ish, I think the growing depends on lines, but that seems on track to me.
As far as heat cycles that can vary from dog to dog. My Corso went into her first heat at 8 months, her sister at 14 months and I know dogs who didn't until 1.5 years...
I wouldn't spay until after her first heat cycle, but that is just me personally.
 

BlackShadowCaneCorso

Super Moderator
Staff member
Mastiffs grow at a different rates, one of my female corsi matured very quickly after her first year, my second is just starting to fill in now. There heat cycles were also very different, my female that matured fast had her heat cycle earlier (11 months) but my other female came in around 18 months I think for the first time. So it can vary but if you have the option to wait until she is mature to fix I would, just my personal preference.


Lillie just turned 9 months old. I have been told she will grow her height for 2 yrs and her bulk for the next 2 yrs. Is that true. I'm not rushing her growth, I know not to do that. I'm just curious. Also when does a large breed dog go into their first heat cycle? ( usually ). I'm not going to breed her so I have also read that she shouldn't be spayed until she is over a year or it can cause health problems later in life. Have I read it right?
Thanks in advance.
 
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moose

Well-Known Member
I agree with the above posts, I would say around three is when they stop growing. I would also wait if you are able to spay until after first heat.
 

lilliesmomma

Well-Known Member
Thanks everyone. I am able to wait until after her first heat to spay her. I can wait as long as I need to so as not to cause future health problems.
 

lilliesmomma

Well-Known Member
Well, I'm here to tell you my dogs never do what is normal. The other day I looked at her and she looked swollen and I thought to myself; she is going into heat but thought it was too soon, nope, she is in heat now. Oh well. Here's to hoping her first heat is a light one. She will be spayed after she turns a year.
Thanks for your help.
 

rebeccagrooms

New Member
My English Mastiff just started her first heat and she is 18 months old, however my vet thinks she may have had a "silent heat" previously which would have given us absolutley no signs of heat.
 

kelsekins

New Member
Hey just wanted to let you know that we have a Cane Corso puppy named Dixie who is almost 6 months old, and I have been talking to a breeder who has been breeding Cane Corso's for 16 or so years and she recommended that we get her spayed BEFORE her first heat. She said it reduces the chance of cancer later in the dog's life by 80%. Just thought I'd add that to the discussion! :)
 

Smart_Family

Dog Food Guru
Hey just wanted to let you know that we have a Cane Corso puppy named Dixie who is almost 6 months old, and I have been talking to a breeder who has been breeding Cane Corso's for 16 or so years and she recommended that we get her spayed BEFORE her first heat. She said it reduces the chance of cancer later in the dog's life by 80%. Just thought I'd add that to the discussion! :)
Well unfortunately that's not the case and it doesn't matter how long she's been breeding. Giant breeds should ideally not be fixed before 18-24 months for a number of reasons.
 

NeoBull

Well-Known Member
I think most large and giant breed dogs stop growing in height between 12-18months and will widen/fill out till 2-3 years. My Neo/BM cross went into heat about a week before she turned 12 months.

My vet breeds and shows BM's and says 18 months minimum to spay/neuter which goes along with everything I've read about spaying/neutering large and giant breeds.
 

daisydx5

New Member
Growth plates are mature around 30-36 months of age. I work at a vet's office and we always recommend spay and neuter before the first heat or at or around 6-7 months old. There has been no significant research concluding health problems from castration before a year in age. We do it every day. Also, it will reduce her chances of getting mammary cancer to almost nil if spayed before first heat. Each time she has a heat cycle the percentage goes up.
Lillie just turned 9 months old. I have been told she will grow her height for 2 yrs and her bulk for the next 2 yrs. Is that true. I'm not rushing her growth, I know not to do that. I'm just curious. Also when does a large breed dog go into their first heat cycle? ( usually ). I'm not going to breed her so I have also read that she shouldn't be spayed until she is over a year or it can cause health problems later in life. Have I read it right?
Thanks in advance.
 

DMikeM

Well-Known Member
18 to 24 months is the preferred minimum age for any large breed and especially mastiffs. Growth hormones are controlled by the sex organs hormones there are also mental and psychological maturity issues starting to be discovered. If you can safely wait it out it would be the best thing overall for your mastiff.
 

TWW

Well-Known Member
I'll call bull, actually there have been several studies that say the direct opposite. With male mastiff you have a what 1.5% greater chance of testicular cancer which is 90% survival rate. and can list a huge amount that have been shown to happen with prior to full maturity with a much lower survival rate. Pyo is the best reason to spay after 2 years in the case of a female.
Please pm me if you need a huge list of research that says there is a difference. Also I can post pics for anyone to judge.
Growth plates are mature around 30-36 months of age. I work at a vet's office and we always recommend spay and neuter before the first heat or at or around 6-7 months old. There has been no significant research concluding health problems from castration before a year in age. We do it every day. Also, it will reduce her chances of getting mammary cancer to almost nil if spayed before first heat. Each time she has a heat cycle the percentage goes up.
 

DMikeM

Well-Known Member
Here is a list of most of the current findings regarding spay or neuter of dogs.
Spay and Neuter Decisions - References

BTW the USA is the only country that tries to force unnecessary gonadectomy on animals and we have the highest rate of bone cancers and health issues in dogs comparatively. Other countries manage their animals and prevent unwanted litters instead of removing organs.
 

DMikeM

Well-Known Member
Growth plates are mature around 30-36 months of age. I work at a vet's office and we always recommend spay and neuter before the first heat or at or around 6-7 months old. There has been no significant research concluding health problems from castration before a year in age. We do it every day. Also, it will reduce her chances of getting mammary cancer to almost nil if spayed before first heat. Each time she has a heat cycle the percentage goes up.

You work for a vet and you really believe that? Please read this website and go educate your boss.
Long-Term Health Risks and Benefits Associated with Spay / Neuter in Dogs

important excerpt from the site.
[FONT=Arial, Helvetica, sans-serif]An objective reading of the veterinary medical literature reveals a complex situation with respect to the longterm health risks and benefits associated with spay/neuter in dogs. The evidence shows that spay/neuter correlates with both positive AND adverse health effects in dogs. It also suggests how much we really do not yet understand about this subject.[/FONT]
[FONT=Arial, Helvetica, sans-serif] On balance, it appears that no compelling case can be made for neutering most male dogs, especially immature male dogs, in order to prevent future health problems. The number of health problems associated with neutering may exceed the associated health benefits in most cases.[/FONT]
[FONT=Arial, Helvetica, sans-serif] On the positive side, neutering male dogs[/FONT]
[FONT=Arial, Helvetica, sans-serif]• eliminates the small risk (probably <1%) of dying from testicular cancer
• reduces the risk of non-cancerous prostate disorders
• reduces the risk of perianal fistulas
• may possibly reduce the risk of diabetes (data inconclusive)[/FONT]
[FONT=Arial, Helvetica, sans-serif] [/FONT]
[FONT=Arial, Helvetica, sans-serif] On the negative side, neutering male dogs[/FONT]
[FONT=Arial, Helvetica, sans-serif]• if done before 1 year of age, significantly increases the risk of osteosarcoma (bone cancer); this is a
common cancer in medium/large and larger breeds with a poor prognosis.
• increases the risk of cardiac hemangiosarcoma by a factor of 1.6
• triples the risk of hypothyroidism
• increases the risk of progressive geriatric cognitive impairment
• triples the risk of obesity, a common health problem in dogs with many associated health problems
• quadruples the small risk (<0.6%) of prostate cancer• doubles the small risk (<1%) of urinary tract cancers
• increases the risk of orthopedic disorders
• increases the risk of adverse reactions to vaccinations[/FONT]
[FONT=Arial, Helvetica, sans-serif]For female dogs, the situation is more complex. The number of health benefits associated with spaying may exceed the associated health problems in some (not all) cases. On balance, whether spaying improves the odds of overall good health or degrades them probably depends on the age of the female dog and the relative risk of various diseases in the different breeds.[/FONT]
[FONT=Arial, Helvetica, sans-serif] On the positive side, spaying female dogs[/FONT]
[FONT=Arial, Helvetica, sans-serif]• if done before 2.5 years of age, greatly reduces the risk of mammary tumors, the most common
malignant tumors in female dogs
• nearly eliminates the risk of pyometra, which otherwise would affect about 23% of intact female
dogs; pyometra kills about 1% of intact female dogs
• reduces the risk of perianal fistulas• removes the very small risk (0.5%) from uterine, cervical, and ovarian tumors
[/FONT]
[FONT=Arial, Helvetica, sans-serif] On the negative side, spaying female dogs[/FONT]
[FONT=Arial, Helvetica, sans-serif]• if done before 1 year of age, significantly increases the risk of osteosarcoma (bone cancer); this is a
common cancer in larger breeds with a poor prognosis
• increases the risk of splenic hemangiosarcoma by a factor of 2.2 and cardiac hemangiosarcoma by a factor of >5; this is a common cancer and major cause of death in some breeds
• triples the risk of hypothyroidism
• increases the risk of obesity by a factor of 1.6-2, a common health problem in dogs with manyassociated health problems
• causes urinary “spay incontinence” in 4-20% of female dogs
• increases the risk of persistent or recurring urinary tract infections by a factor of 3-4
• increases the risk of recessed vulva, vaginal dermatitis, and vaginitis, especially for female dogsspayed before puberty
• doubles the small risk (<1%) of urinary tract tumors
• increases the risk of orthopedic disorders• increases the risk of adverse reactions to vaccinations[/FONT]
[FONT=Arial, Helvetica, sans-serif]

One thing is clear * much of the spay/neuter information that is available to the public is unbalanced and contains claims that are exaggerated or unsupported by evidence. Rather than helping to educate pet owners, much of it has contributed to common misunderstandings about the health risks and benefits associated of spay/neuter in dogs.[/FONT]
[FONT=Arial, Helvetica, sans-serif] The traditional spay/neuter age of six months as well as the modern practice of pediatric spay/neuter appear to predispose dogs to health risks that could otherwise be avoided by waiting until the dog is physically mature, or perhaps in the case of many male dogs, foregoing it altogether unless medically necessary.[/FONT]
[FONT=Arial, Helvetica, sans-serif]The balance of long-term health risks and benefits of spay/neuter will vary from one dog to the next. Breed, age, and gender are variables that must be taken into consideration in conjunction with non-medical factors for each individual dog. Across-the-board recommendations for all pet dogs do not appear to be supportable from findings in the veterinary medical literature.[/FONT]
 

TWW

Well-Known Member
As DMikeM has supplied the links to debunk your theory of no difference.

Simple pics as to a mastiff neuter at 6 months vs one not neutered.

Please let me know if you don't notice a difference in muscle, muzzle, and general build.

Also yes there from the same lines.
 

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DMikeM

Well-Known Member
They don't even look like the same breed of dog regardless of color. How sad.

As DMikeM has supplied the links to debunk your theory of no difference.

Simple pics as to a mastiff neuter at 6 months vs one not neutered.

Please let me know if you don't notice a difference in muscle, muzzle, and general build.

Also yes there from the same lines.
 

kguitarchic18

Well-Known Member
From lots of research and as others have said here, they grow/fill out until about 3 years. And I am going with the wait until at least 18 months. Zola went into her first heat at 10 months, and maybe thats an indication that she has matured a little faster as she hasnt gotten much bigger, but has filled out slightly more the last month or two. I have also heard they come out of their first heat a little more mature, and its true zola just acted more grown up and calm and got a little beeffier. She just got done with her second heat and just hit 18 months. One vet we talked too (unfortunately a lot of vets out here dont seem to be knowledgeable about larger breeds) kept asking us why we thought we needed to wait until 18 months, and that letting her go through a heat or two was putting her at risk for more stuff.

Our main vet that is kinda far, is very old school (he clipped her ears and we had no issues) didn't say one thing about waiting. He just said to wait a few weeks after she came off her heat to bring her in. We also are going to have her stomach tacked (gastroplexy) while she is getting fixed.