Thought this was interesting:
http://www.dogsnaturallymagazine.com/your-dog-needs-to-be-spayed-or-neutered-right/

With that being said what are the chances of your bitch getting Pyro? Cause am thinking on leaving Moose
intact really don't see the need to mess with her insides. Not planning on breeding just want to give her the
best life she can have. So far we want to keep her the way she is.
Junior is still intact & he's 13 1/2yrs old and still
doing good- a lil wonky in the back legs, blind & a lil senile lol but he can still hear & still does his business outside.

Not much chance of Pyro at all... Pyo on the other hand.... :-p (sorry, overtired and couldn't resist!) I certainly wouldn't spay / neuter a young dog or bitch, it's not difficult to manage seasons, though trickier if you have males too. My old boy now gone always got in a terrible state when my girl was in season, we had to send him to a friend whenever possible. I am now though starting to wonder if I should spay my girl who is 8.5 years old now.

> if I should spay my girl who is 8.5 years old now

There are some that prefer to spay bitches at a late age, as it's research says that a late spayed bitch has better longevity.

I would do her now LucyDogs, while she is still fit and well.  Then there are no emergency spays due to pyometra.    My vet reckons that I am the only person who takes in older bitches for spaying.  The others listen to him and get them spayed early.  I tend to act deaf, and ignore the comments.   :-)

Can't remember the statistics on Pyo, higher in middle aged to elderly bitches who have never been bred from, but still a significant number even from breeding bitches.

For this reason I spay all mine after their last litter.

If your still wanting to show yoru girl in your breed I know spaying negatively affects the coat. 

Fortuantely in mine it does not so it means if I am not sure if a bitch is likely to be in season for a show I can enter the spayed veteran instead.

>If your still wanting to show yoru girl in your breed I know spaying negatively affects the coat.

That's my dilemma - obviously her health comes first, but depending on how high a risk it is, I don't want to spoil her coat and end her veteran career and turn her into one of those wooly heathrug Cavaliers before I have to!

Just tagging on to the end here, not replying to anyone in particular. I don't spay mine until around the age of 8 if there is ANY chance I may want another litter. For instance I have a 7 year old bitch at the moment, she has had 2 litters and I have absolutely no plans whatsoever for her to have any more pups. But I don't want to spay her until she is too old to be bred from, just in case. I have visions of a disaster happening, say a fire, with all my other bitches dying and everything being lost, and the only bitch left having been spayed. (Okay I have an active imagination!!) When it is a bitch I know I most definitely would not want to breed from no matter what, I'd do it around 3 for a large breed. Earlier for my toys. I would not want to leave a bitch entire for life due to the risk of pyometra, and the risks of surgery in en elderly bitch. Twice I have left bitches unspayed, BOTH developed pyo aged 9 and 10.

I spayed my girls at eight and six..they both came through the op fine. The first dog had polycystic ovaries...her seasons were every 8 to 9 months , and she bled for 4 weeks each time...she had had three seizures when young so I wasn't keen to put her under a GA,but it all worked out well.
The second dog started to have phantoms ...the spay  went ok,but afterwards she suffered from incontinence ,which we deal with using incurin.

I groom a CKC who is spayed...she does have a very wavy ,thick coat......I strip the body twice a year and she keeps the silky,thinner coat typical of the breed.

Seems to me that Pyo is your biggest worry but there are some others.  I notice this article mentions the CBARQ study on behaviour that shows MORE aggression in altered dogs and especially in bitches.  That's a generalization, if you have one of the individual breeds studied you see it does vary quite a bit by breed.  In this list I highlighted that behaviour study in red so you can find it more easily.

Oops, no, seems red is not available so I copied it to third position.

This is a reading list of articles and papers by Veterinarians, breed clubs, trainers and others on the pros and cons of neutering or spaying your dog that I have found helpful and very educational. Most are based on extensive Veterinary research and also provide references you can check further. If you are wrestling with the question of when or whether to neuter/spay these may help. They do not all agree and one is even a rebuttal of another. One is a link to a radio show interview. One is a link to a medical testosterone suppressant not yet available in N. America but is in the U.K. and Australia. Some are not easy reading.

I think I personally found the first two in the list to be of most help and I appreciated the non-biased way the information was presented. The list is in no particular order, articles were simply added as I discovered them. If the links are not clickable I have tried to include the name of the paper and author in case you have to search for them. I hope this helps folks out and good luck with your decision. A tip, I went to my Vet to discuss the first two articles with her.

http://www.naiaonline.org/pdfs/LongTermHealthEffectsOfSpayNeuterInDogs.pdf
Long-Term Health Risks and Benefits Associated with Spay / Neuter in Dogs
Laura J. Sanborn, M.S.
May 14, 2007

http://avmajournals.avma.org/doi/pdf/10.2460/javma.231.11.1665
Determining the optimal age for gonadectomy of dogs and cats,
Margaret V. Root Kustritz, dvm, phd, dact

http://www.cdoca.org/downloads/files/Early%20SN%20and%20Behavior.pdf
Non-reproductive Effects of Spaying and Neutering on Behavior in Dogs
Deborah L. Duffy, Ph.D., and James A. Serpell, Ph.D., Center for the Interaction of
Animals and Society, School of Veterinary Medicine, University of Pennsylvania

http://www.savethedals.org/earlyneuter.htm
Veterinary "Review" Article on Neutering, with Implications for Dalmatian Stone-Formers    Abstracted by Carroll H. Weiss
Study Group on Urinary Stones
Research Committee
Dalmatian Club of America

http://www.showdogsupersite.com/kenlclub/breedvet/neutr.html
NEUTERING MALE AND FEMALE DOGS
Mary C. Wakeman, D.V.M.
©2003 for BREEDERVET

http://www.littleriverlabs.com/neuter.htm
The Question Of Neutering and at what age
(Put together by Gregg Tonkin, Little River Labradors from postings by Pam Davol PHD and Chris Zink DVM, PhD, DACVP)

http://leerburg.com/pdf/neutering.pdf
Should You Neuter Your Dog?
Ed Frawley, Leerburg Kennels   * words are l e e r b u r g.com and L e e r b u r g Kennels

http://www.traciehotchner.com/dt/files/WillWeChangeOnEarlySpay-Neuter_Villalobos.pdf
The Bond and Beyond for VPN December 2008
by Alice Villalobos
Will We Change on Early Spay-Neuter?

http://www.showdogsupersite.com/kenlclub/breedvet/castrationindogs.html
ISSUES REGARDING CASTRATION IN DOGS
Mary C. Wakeman, D.V.M.
©2003 for BREEDERVET

http://www.petresource.com/Articles%20of%20Interest/new_views_on_neutering.htm
New Views On Neutering
By Ruth Marrion, DVM

http://www.acc-d.org/2006%20Symposium%20Docs/Session%20I.pdf
Non-reproductive Effects of Spaying and Neutering
Proceedings of the Third International Symposium on Non-Surgical
Contraceptive Methods for Pet Population Control * www.acc-d.org
SESSION OVERVIEW - Dr. John Verstegen

http://www.peptech.com/HTML/Animal_Health/Superlorin_general.html
A non-surgical method to suppress testosterone

http://prdupl02.ynet.co.il/ForumFiles_2/23999370.pdf
Pros and Cons of Neutering
E. Hardie
Department of Clinical Sciences, North Carolina State University, Raleigh, NC, USA.

http://www.doglistener.co.uk/neutering/rspca.shtml
RSPCA Admit to Spaying and Castrating Puppies AT SIX WEEKS OLD
Stan Rawlinson MTCBPT.MPAACT
Doglistener Behaviourist and Obedience Trainer

http://users.lavalink.com.au/theos/Spay-neuter.htm#vacc
Should I spay or should I no..?  -- pros and cons of Spay-neuter
Hungarian Vizsla Health Resource

http://www.doglistener.co.uk/neutering/spaying_neutering.shtml
Spaying and Castration (Neutering) Dogs and Cats A Stark Warning
Stan Rawlinson, a full time Dog Behaviourist and Obedience Trainer.

http://www.wholedognews.com/
Spay, Neuter, and Cancer: Revisiting and Old Trinity
Myrna Milani, BS, DVM

http://www.caninesports.com/SpayNeuter.html
Early Spay-Neuter Considerations for the Canine Athlete One Veterinarian's Opinion
© 2005 Chris Zink DVM, PhD, DACVP

http://www.columbusdogconnection.com/Documents/PedRebuttal%20.pdf
Rebuttal to "Early Spay-Neuter Considerations for the Canine Athlete"
Lisa M Howe, DVM, PhD, Dipl. ACVS Associate Professor, Small Animal Surgery Co-Chief
Surgical Sciences Sect Dept of Vet Small Animal Clinical Sci
College of Vet Med and Biom Sciences Texas A&M Univ College Station TX 77843

http://www.pluggd.tv/audio/channels/dog_talk_the_radio_show/episodes/4njnh
Dog Talk Show #96 Tracie Hotchner (10-18-2008)
Early spay/neuter may be harming our dogs! Hear Dr. Christine Zink, DVM, PhD, DAVCP on the physical benefits of delaying neutering and trainer Parvene Farhoody on how it can reduce aggression.

http://www.antrozoologisenteret.no/artikler/art_breed.pdf
Effects of breed, sex, and neuter status on trainability in dogs
James A. Serpell* and Yuying Hsu+

http://users.skynet.be/fa242124/a-english/castration-dogs.html
Gonadectomy and behavior
Dr Joël Dehasse

http://homepage.psy.utexas.edu/homepage/faculty/Gosling/reprints/AABS05DogPersonalityReview.pdf
Temperament and personality in dogs (Canis familiaris): A review and evaluation of past research
Amanda C. Jones *, Samuel D. Gosling

http://www.skeptvet.com/index.php?p=1_23_Benefits-Risks-of-Neutering
Evaluating the Benefits and Risks of Neutering
The SkeptVet -  the owner of this blog is not identified but the articles referenced are searchable.

http://www.petfinder.com/for-shelters/pediatric-spay-neuter.html
Pediatric Spay/Neuter
Dr. Lila Miller, ASPCA

http://k9harmony.co.uk/spaying-and-castration/
Spaying and Castration - What Your Vet and the Rescue Centres May Not Tell You
Pauline Waller, member #178 Professional Association of Applied Canine Trainers, - articles referenced and searchable

http://www.champdogsforum.co.uk/cgi-bin/board/topic_show.pl?pid=1123732;hl=castrate#pid1123732
To Castrate or Not? - Interesting discussion regarding a young male targeted by an aggressive older male.

http://www.cdoca.org/downloads/files/Early%20SN%20and%20Behavior.pdf
Non-reproductive Effects of Spaying and Neutering on Behavior in Dogs
Deborah L. Duffy, Ph.D., and James A. Serpell, Ph.D., Center for the Interaction of
Animals and Society, School of Veterinary Medicine, University of Pennsylvania

http://www.2ndchance.info/spayneuter.htm
At What Age Should I Spay or Neuter My Dog or Cat?
What Are The Advantages And Disadvantages Of Neutering My Pet?
Revisiting The Idea Of Early-Age Neutering
Ron Hines DVM PhD  10/05/09

http://saveourdogs.net/category/health/
Articles and links to Veterinary organizations opposing mandatory spay/neuter

http://askdryin.com/blog/tag/dog-behavior-arousal-aggression-spay-neuter/
Can Spaying Make Dog Behaviour Worse?
Sophia Yin, DVM, MS        March 5, 2009

http://www.associationofanimalbehaviorprofessionals.com/effects_of_neutering.html
The Effects of Spaying and Neutering on Canine Behaviour
James O'Heare, Based on section from Aggressive Behavior in Dogs, 2006,

http://www.petfriendlyworld.com/chatforum/showthread.php?t=23096
The Behavioural Effects of Canine Castration
Hazel Palmer, 1993  See post #8 in the chat forum at Pet Friendly World.

http://www.cdoca.org/downloads/files/Early%20SN%20and%20Behavior.pdf
Does Spaying and Neutering Reduce Aggression?
Dr. Polley DVM, 2001   American Dog Breeders Association

http://www.gpmcf.org/respectovaries.html
A Healthier Respect for Ovaries (in dogs)
David J. Waters, DVM, PhD, Diplomate ACVS
Director, Center for Exceptional Longevity Studies
Gerald P. Murphy Cancer Foundation

http://news.uns.purdue.edu/x/2009b/091201OvarianResearch.html
Message for women and dogs: keeping ovaries is linked to longevity
To the Purdue Research Park, http://www.purdueresearchpark.com

http://www.rockllewellinsetters.com/OvaryExposureLongevityStudyfromAgingCellJournalbyDavidJWatersetalDec2009.pdf
Exploring mechanisms of sex differences in longevity:  lifetime ovary exposure and exceptional longevity in dogs
David J. Waters,1,2 Seema S. Kengeri,1 Beth Clever,1 Julie A. Booth,1 Aimee H. Maras,1 Deborah L.
Schlittler1 and Michael G. Hayek3
http://www.avma.org/onlnews/javma/may09/090515j.asp
AVMA: Mandatory spay/neuter a bad idea
Javma News, May 15, 2009

http://www.pet-informed-veterinary-advice-online.com/male-dog-neutering.html
Veterinary Advice Online:  Male Dog Neutering

http://www.pet-informed-veterinary-advice-online.com/dog-spaying.html
Veterinary advice Online:  Dog Spaying (Spaying a Female Dog)
Dr. Shauna O'Meara  Pet Informed:  http://www.pet-informed-veterinary-advice-online.com/index.html

http://www.journals.elsevierhealth.com/periodicals/applan/article/S0168-1591(08)00114-7/abstract
Breed differences in canine aggression 1, Dec. 2008
Deborah L. Duffy, Yuying Hsub, James A. Serpella

http://cebp.aacrjournals.org/content/11/11/1434.full
Endogenous Gonadal Hormone Exposure and Bone Sarcoma Risk
Dawn M. Cooley, Benjamin C. Beranek, Deborah L. Schlittler, Nita W. Glickman, Lawrence T. Glickman, and David J. Waters

http://www.stbernardhealth.co.uk/pyometrainthebitch.htm
Pyometra in the Bitch
Jenny King

http://www.akcchf.org/news-events/multimedia/podcasts/early-spay-and-neuter.html
Early Spay and Neuter 
Podcast with Dr. Benjamin Hart

http://www.akcchf.org/canine-health/your-dogs-health/bone-cancer-in-dogs.html
Bone Cancer in Dogs
Dr. Jaime Modiano

http://news.ucdavis.edu/search/news_detail.lasso?id=10498
Golden Retriever Study Suggests Neutering Affects Dog Health
UC Davis, News and Information.  Media Contacts:  Benjamin Hart, School of Veterinary Medicine,  (530) 752-1555, blhart@ucdavis.edu;  Pat Bailey, UC Davis News Service,  (530) 752-9843, pjbailey@ucdavis.edu

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0055937
Neutering Dogs: Effects on Joint Disorders and Cancers in Golden Retrievers
Gretel Torres de la Riva, Benjamin L. Hart ,XThomas B. Farver, Anita M. Oberbauer, Locksley L. McV. Messam, Neil Willits, Lynette A. Hart

I would spay between the ages of 6-8yrs, whether a bitch has been bred from or not.  I'd also only do a laparoscopic spay now, after having seen how much quicker and and pain-free the op is compared to a conventional spay.

My Kezzie was spayed aged 8 + by laparoscopic surgery. We decided to spay because her heat seasons were coming every 3 months or so and with boys around this was very difficult to manage. I also feared pyometra would eventually occur. She was up and around within 24 hours and escaped to join in doggie tennis the following day. No change in temperament but longstanding 'issues ' with another girl in our family disappeared within a couple of months. She has intermittent/rare episodes of incontinence of urine  at night but was otherwise fine until a few weeks ago when aged 12 + she suffered a vestibular/cerebral incident  - collapse with vomitting and head tilt. She's even recovering well from that -just the occasional back leg wobble.

Laparoscopic spays around here are £350, compared to £250 for everything out.  For thsoe where money is tight (most of us) that's a big difference.

I would always worry about the risk of Pyo with the uterus left in.  I know that should be rare due to teh hormone producign untis largely removed, but as Stump Pyometra occurs I worry a bit about it being more likely with the uterus left in place.

I know from friends living in France that Laparoscopic/removal of ovaries only spays there are the norm.

Not sure what I am gonna do- am thinking prob spay her once the Boston's pass on- so prob not till she is
about 3 yrs old- have not totally decided as of yet- have some time to research and a lot of thinking for sure.
If we do I def want to do it in the winter & not the summer since hubby will be home with her during that time.