Study on Spay/Neuter - UC Davis
Sorry if this has already been posted before, but I thought it was important enough to risk of repeating if it hasn't.
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http://news.ucdavis.edu/search/news_detail.lasso?id=10498
*Golden retriever study suggests neutering affects dog health*
February 13, 2013
Neutering, and the age at which a dog is neutered, may affect the
animal’s risk for developing certain cancers and joint diseases,
according to a new study of golden retrievers by a team of researchers
at the University of California, Davis.
The study, which examined the health records of 759 golden retrievers,
found a surprising doubling of hip dysplasia among male dogs neutered
before one year of age. This and other results will be published today
(Feb. 13) in the online scientific journal PLOS ONE
http://dx.plos.org/10.1371/journal.pone.0055937 .
“The study results indicate that dog owners and service-dog trainers
should carefully consider when to have their male or female dogs
neutered,” said lead investigator Benjamin Hart, a distinguished
professor emeritus in the UC Davis School of Veterinary Medicine.
“It is important to remember, however, that because different dog breeds
have different vulnerabilities to various diseases, the effects of early
and late neutering also may vary from breed to breed,” he said.
While results of the new study are revealing, Hart said the relationship
between neutering and disease-risk remains a complex issue. For example,
the increased incidence of joint diseases among early-neutered dogs is
likely a combination of the effect of neutering on the young dog’s
growth plates as well a s the increase in weight on the joints that is
commonly seen in neutered dogs.
Dog owners in the United States are overwhelmingly choosing to neuter
their dogs, in large part to prevent pet overpopulation or avoid
unwanted behaviors. In the U.S., surgical neutering — known as spaying
in females — is usually done when the dog is less than one year old.
In Europe, however, neutering is generally avoided by owners and
trainers and not promoted by animal health authorities, Hart said.
During the past decade, some studies have indicated that neutering can
have several adverse health effects for certain dog breeds. Those
studies examined individual diseases using data drawn from one breed or
pooled from several breeds.
Against that backdrop, Hart and colleagues launched their study, using a
single hospital database. The study was designed to examine the effects
of neutering on the risks of several diseases in the same breed,
distinguishing between males and females and between early or late
neutering and non-neutering.
The researchers chose to focus on the golden retriever because it is one
of the most popular breeds in the U.S. and Europe and is vulnerable to
various cancers and joint disorders. The breed also is favored for work
as a service dog.
The research team reviewed the records of female and male golden
retrievers, ranging in age from 1 to 8 years, that had been examined at
UC Davis’ William R. Pritchard Veterinary Medical Teaching Hospital for
two joint disorders and three cancers: hip dysplasia, cranial cruciate
ligament tear, lymphosarcoma, hemangiosarcoma and mast cell tumor. The
dogs were classified as intact (not neutered), neutered early (before 12
months age), or neutered late (at or after 12 months age).
Joint disorders and cancers are of particular interest because neutering
removes the male dog’s testes and the female’s ovaries, interrupting
production of certain hormones that play key roles in important body
processes such as closure of bone growth plates, and regulation of the
estrous cycle in female dogs.
The study revealed that, for all five diseases analyzed, the disease
rates were significantly higher in both males and females that were
neutered either early or late compared with intact (non-neutered) dogs.
Specifically, early neutering was associated with an increase in the
occurrence of hip dysplasia, cranial cruciate ligament tear and
lymphosarcoma in males and of cranial cruciate ligament tear in females.
Late neutering was associated with the subsequent occurrence of mast
cell tumors and hemangiosarcoma in females.
In most areas, the findings of this study were consistent with earlier
studies, suggesting similar increases in disease risks. The new study,
however, was the first to specifically report an increased risk of late
neutering for mast cell tumors and hemangiosarcoma.
Furthermore, the new study showed a surprising 100 percent increase, or
doubling, of the incidence of hip dysplasia among early-neutered males.
Earlier studies had reported a 17 percent increase among all neutered
dogs compared to all non-neutered dogs, indicating the importance of the
new study in making gender and age-of-neutering comparisons.
Other researchers on this UC Davis study were: Gretel Torres de la Riva,
Thomas Farver and Lynette Hart, School of Veterinary Medicine; Anita
Oberbauer, Department of Animal Science; Locksley Messam, Department of
Public Health Sciences; and Neil Willits, Department of Statistics.
*About UC Davis*
For more than 100 years, UC Davis has engaged in teaching, research and
public service that matter to California and transform the world.
Located close to the state capital, UC Davis has more than 33,000
students, more than 2,500 faculty and more than 21,000 staff, an annual
research budget of nearly $750 million, a comprehensive health system
and 13 specialized research centers. The university offers
interdisciplinary graduate study and more than 100 undergraduate majors
in four colleges — Agricultural and Environmental Sciences, Biological
Sciences, Engineering, and Letters and Science. It also houses six
professional schools — Education, Law, Management, Medicine, Veterinary
Medicine and the Betty Irene Moore School of Nursing.
============================================
http://news.ucdavis.edu/search/news_detail.lasso?id=10498
*Golden retriever study suggests neutering affects dog health*
February 13, 2013
Neutering, and the age at which a dog is neutered, may affect the
animal’s risk for developing certain cancers and joint diseases,
according to a new study of golden retrievers by a team of researchers
at the University of California, Davis.
The study, which examined the health records of 759 golden retrievers,
found a surprising doubling of hip dysplasia among male dogs neutered
before one year of age. This and other results will be published today
(Feb. 13) in the online scientific journal PLOS ONE
http://dx.plos.org/10.1371/journal.pone.0055937 .
“The study results indicate that dog owners and service-dog trainers
should carefully consider when to have their male or female dogs
neutered,” said lead investigator Benjamin Hart, a distinguished
professor emeritus in the UC Davis School of Veterinary Medicine.
“It is important to remember, however, that because different dog breeds
have different vulnerabilities to various diseases, the effects of early
and late neutering also may vary from breed to breed,” he said.
While results of the new study are revealing, Hart said the relationship
between neutering and disease-risk remains a complex issue. For example,
the increased incidence of joint diseases among early-neutered dogs is
likely a combination of the effect of neutering on the young dog’s
growth plates as well a s the increase in weight on the joints that is
commonly seen in neutered dogs.
Dog owners in the United States are overwhelmingly choosing to neuter
their dogs, in large part to prevent pet overpopulation or avoid
unwanted behaviors. In the U.S., surgical neutering — known as spaying
in females — is usually done when the dog is less than one year old.
In Europe, however, neutering is generally avoided by owners and
trainers and not promoted by animal health authorities, Hart said.
During the past decade, some studies have indicated that neutering can
have several adverse health effects for certain dog breeds. Those
studies examined individual diseases using data drawn from one breed or
pooled from several breeds.
Against that backdrop, Hart and colleagues launched their study, using a
single hospital database. The study was designed to examine the effects
of neutering on the risks of several diseases in the same breed,
distinguishing between males and females and between early or late
neutering and non-neutering.
The researchers chose to focus on the golden retriever because it is one
of the most popular breeds in the U.S. and Europe and is vulnerable to
various cancers and joint disorders. The breed also is favored for work
as a service dog.
The research team reviewed the records of female and male golden
retrievers, ranging in age from 1 to 8 years, that had been examined at
UC Davis’ William R. Pritchard Veterinary Medical Teaching Hospital for
two joint disorders and three cancers: hip dysplasia, cranial cruciate
ligament tear, lymphosarcoma, hemangiosarcoma and mast cell tumor. The
dogs were classified as intact (not neutered), neutered early (before 12
months age), or neutered late (at or after 12 months age).
Joint disorders and cancers are of particular interest because neutering
removes the male dog’s testes and the female’s ovaries, interrupting
production of certain hormones that play key roles in important body
processes such as closure of bone growth plates, and regulation of the
estrous cycle in female dogs.
The study revealed that, for all five diseases analyzed, the disease
rates were significantly higher in both males and females that were
neutered either early or late compared with intact (non-neutered) dogs.
Specifically, early neutering was associated with an increase in the
occurrence of hip dysplasia, cranial cruciate ligament tear and
lymphosarcoma in males and of cranial cruciate ligament tear in females.
Late neutering was associated with the subsequent occurrence of mast
cell tumors and hemangiosarcoma in females.
In most areas, the findings of this study were consistent with earlier
studies, suggesting similar increases in disease risks. The new study,
however, was the first to specifically report an increased risk of late
neutering for mast cell tumors and hemangiosarcoma.
Furthermore, the new study showed a surprising 100 percent increase, or
doubling, of the incidence of hip dysplasia among early-neutered males.
Earlier studies had reported a 17 percent increase among all neutered
dogs compared to all non-neutered dogs, indicating the importance of the
new study in making gender and age-of-neutering comparisons.
Other researchers on this UC Davis study were: Gretel Torres de la Riva,
Thomas Farver and Lynette Hart, School of Veterinary Medicine; Anita
Oberbauer, Department of Animal Science; Locksley Messam, Department of
Public Health Sciences; and Neil Willits, Department of Statistics.
*About UC Davis*
For more than 100 years, UC Davis has engaged in teaching, research and
public service that matter to California and transform the world.
Located close to the state capital, UC Davis has more than 33,000
students, more than 2,500 faculty and more than 21,000 staff, an annual
research budget of nearly $750 million, a comprehensive health system
and 13 specialized research centers. The university offers
interdisciplinary graduate study and more than 100 undergraduate majors
in four colleges — Agricultural and Environmental Sciences, Biological
Sciences, Engineering, and Letters and Science. It also houses six
professional schools — Education, Law, Management, Medicine, Veterinary
Medicine and the Betty Irene Moore School of Nursing.
Comments
For a GSD or dog that matures in height over two years it may have been later in life. I think it depends on the breed.
However, pyro has been shown to have a genetic link, probably auto-immunal, according to a survey from an insurance company:
http://konnunkodon.fi/blogi-en/2013/01/05/incidence-of-pyometra-and-mammary-tumours-in-swedish-vallhunds/
http://www.naiaonline.org/pdfs/LongTermHealthEffectsOfSpayNeuterInDogs.pdf
http://www.plosone.org/article/info:doi/10.1371/journal.pone.0055937
Tardax: http://www.myvetmeds.co.uk/tardak-injection-10-ml.htm
And I read this as saying one of the important things to consider is age of neutering, as well. It even starts that way. It's not like someone should never spay/neuter (though some people may choose that route) but that WHEN it is done is important to consider.
Germany, Netherlands et cetera has higher population density than United States, and neutered dogs and spayed are almost non-existent. Leash laws are not enforced either.
And while I still understand why we need spay/neuter programs in the US, and I think we do, I also think we can and should also be concerned about canine health (so not promoting pediatric spay/neuters). We can do both.
I have to agree with @shibamistress.
The problem is that for some reason, in the Anglo-speaking world-- Australia, United States, United Kingdom, Canada, New Zealand et cetera, people have a sense of entitlement everyone should own a dog. Owning a dog is a privilege in Europe. Owning a dog is a unspoken or unwritten right in most English-speaking countries.
I blame John Locke.
The thing is that we wouldn't have these studies on the effects of neutering and spaying if we didn't have our European counterparts.
I could understand cultural differences between countries and reasons for not-neutering. I think it ultimately depends on your environment and situation; for example, if its required to prevent over population in the cities, its a valid concern. There are enough animals in shelters without homes, why create more?
I actually find the study in the link posted by @jackburton to be a great comprehensive one since it's a pretty balanced report touching on a lot of different studies. While the new study is useful, I'm not sure that I'm convinced that focusing on golden retrievers doesn't skew the data a bit. They are a breed with a propensity towards the issues where early spay/neuter correlates to increased risks. While I don't doubt the general conclusion, I'd be curious to know if the numbers would be the same for a breed that didn't have a pre-existing propensity.
That said, I am someone with a spayed girl and an unneutered boy and am disinclined to neuter him when he eventually retired completely from conformation and studding (I don't want him to have any unnecessary surgeries). On the other hand, we live in an area where most spay so I don't need to worry about intact girls driving him nuts.
I usually skim the articles on spay neuter so most of the findings were unsurprising with the exception of the hypothyroid correlation. That one was quite a shock but very interesting.
I do understand the advocacy of spay/neuter in the states though. I remember going to the dog park once and this couple brought both their dogs who were a few years old and unaltered. They stood around chuckling because on occasion they would have to grab the male because the female was in season. The only reason they grabbed him was because apparently he'd recently impregnated their other female and they didn't want to deal with another litter only weeks apart. They had to be asked to leave because it is not only a terrible idea but also against park rules to bring a girl in season. They couldn't understand why everyone found this problematic (and totally missed that there are also unaltered male park regulars who participate in field trials).