It is frequently claimed that breeding dogs on every heat or “back to back breeding” is bad for a bitch’s long term health and well being. However the research in canine reproduction shows that not breeding a dog when it comes into heat can in fact be bad for its health.
Scientist have shown that pseudopregnancy ['phantom pregnancy'] increases the risk of mammary cancers which are the second most common cancer in dogs after skin tumours and are 3-5 times more common than breast cancers in women1:
Pseudopregnancy often occurs when a bitch is not bred. She will show signs such as nesting, weight gain, mammary enlargement and lactation – usually about 6 to 12 weeks after oestrus. Pseudopregnancy represents the extreme of the changes which normally occur during the oestrus cycle and it is suggested that it is a hang over from dogs evolution from wolves. Subordinate non breeding pseudopregnant female wolves in a pack can help to raise pups by nursing the litters of other females” 2
In 1994 Donnay and his associates showed that there is a relationship between the number of pseudopregnancies a bitch goes through and the development of mammary cancer – see Table 1 below3. Verstegen and Onclin (2006)1 have also studied canine mammary cancer and found that a large number of bitches presented for mammary tumours also show pseudopregnancy, that a large percentage of these females had had frequent pseudopregnancies and that the bitches with recurring pseudopregnancy at each cycle tended to develop mammary tumours significantly earlier than other animals.
Both of these authors say that there is need for more research but clearly bitches which don’t breed are likely to become pseudopregnant and pseudopregnancy increases the risk of cancer.
Skipping cycles in breeding has been linked to mammary cancer
Pregnancy protects against life threatening uterine diseases. The most common uterine disease in the bitch is cystic endometrial hyperplasia. It is linked to several serious uterine diseases including the potentially life threatening disease “pyometra” (literally – a uterus full of pus) which affects nearly one quarter of dogs under 10 years old which are not desexed4 . According to canine reproduction specialist Dr S. Romagnoli “bitches whelping regularly throughout their reproductive life almost never develop pyometra, while those who whelp rarely or never in their lives have a greater chance of developing this condition”. Furthermore a standard textbook of veterinary internal medicine notes that uterine diseases are less common in kennels where bitches are bred and conceive regularly indicating that pregnancy has a protective effect on the lining of the uterus or “endometrium”5,6
Given that artificially restricting bitches, which haven’t been desexed, from breeding is bad for their health, it is not surprising that many breeding dogs bred have reproductive problems. If they are show dogs they often don’t start breeding until they are three years old, and have finished their show career, and then kennel club rules and even government regulations require that the bitch is only bred on every second season. Frequently older bitches need veterinary intervention to reproduce, and good bitches may end up being bred well beyond 6 years of age when their fertility is beginning to decline.
No responsible breeder who cares about their dogs would breed their bitches until they are exhausted, and rules certainly need to be in place to ensure that irresponsible breeders don’t exploit their dogs, however the current regulations in place in some states do not take into account the biology of the bitch. Breeding should be regulated by limiting the number of litters a bitch can breed or the age at which they should be desexed and retired.
Breeding dogs regularly while they are young, followed by desexing and rehoming them early is in the best interest of the bitch and a good pet breeder can use this knowledge to work with the natural biology of their animals.
Breeders must be aware of and comply with any government regulations regarding dog breeding in their state and unfortunately in Victoria, NSW and QLD current regulations do not permit this approach to dog breeding.
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|
Pseudopregnancy |
Dogs with history of pseudopregnancy |
Odds Ratio |
|||||
|
Frequency |
|
|
|
|
|
(IC 95%) |
|
|
|
|
With tumours |
without tumours |
|
|
||
|
|
|
|
|
|
|
|
|
|
< 3, |
|
108 |
|
158 |
|
1.5 (0.99 – 2.3) |
|
|
non systematic |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
> 3 , systematic |
73 |
|
109 |
|
1.9 (1.15 – 3) |
||
|
|
|
|
|
|
|
|
|
|
Total |
|
181 |
|
267 |
|
1.6 (1.14-2.3) |
|
|
|
|
|
|
|
|
|
|
Table No 1: Odds ratio for the risk of mammary tumours development related to the frequency of pseudopregnancies. (from Donnay et al. 1994). In this study, bitches with > 3 episodes of pseudopregnancy in their lifetime had a higher risk of developing mammary tumours.
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1. J.P. Verstegen III and K. Onclin. Prolactin and Anti-Prolactinic Agents in the Pathophysiology and Treatment of Mammary Tumors in the Dog. NAVC Proceedings 2006, North American Veterinary Conference (Eds).
2. Canine Pseudopregnancy: A Review (Last Updated: 23-Aug-2001)
C. Gobello1, P. W. Concannon2 and J. Verstegen III3, Recent Advances in Small Animal Reproduction, Concannon P.W., England G., Verstegen III J. and Linde-Forsberg C. (Eds.)
3. Donnay I, Rauis J & Verstegen J – Influence des antécédents hormonaux sur l’apparition clinique des tumeurs mammaires chez la chienne. Etude épidémiologique. Ann. Med. Vet. 1994, 138, 109-117
4. Simón Martí Angulo Clinical aspects of uterine disease in the bitch and queen. Proceeding of the Southern European Veterinary Conference
Oct. 2-4, 2009.
S. Romagnoli, How I Treat… Pyometra. Proceeding of the SEVC
Southern European Veterinary Conference Oct. 17-19, 2008 – Barcelona, Spain
5 Davidson AP, Feldman EC. Ovarian and estrous cycle abnormalities. In:
Ettinger SW, Feldman EC (eds) Textbook of Veterinary Internal Medicine.
WB Saunders, 2004
6 Johnson CA. Cystic endometrial hyperplasia, pyometra, and infertility. In:
Ettinger SW, Feldman EC (eds). Textbook of Veterinary Internal Medicine
WB Saunders, 1992, pp. 954.
About Dr Kate Schoeffel
Good article Kate and very relevant with bitches that are kept undesexed and not bred with. Another interesting factor with bitches not being bred with is ” sexual frustration” which can lead to aggression and behavioural problems. The same with entire dogs as well so if your not going to breed with your dog, have it desexed before maturity to avoid any personality changes due to hormonal flux.
Establishing the temperament of the breeding bitch before she is of breeding age is one of our most important criteria and a good mum will be an asset to her litter being well cared for and healthy and balanced. Bitches breeding large litters dont seem to suffer any undue health problems any more than a bitch who has small litters we have observed here.
Well said Liz, you raise some valid points.
We haven’t had any health problems with bitches who have had large litters either. We recently had a large litter of eleven puppies from a Miniature Australian Labradoodle female and it was her first litter. She was just over two years of age when she was bred.
In some ways, I think large litters and their mothers get the best of both worlds, because breeders usually help out by supplement feeding the puppies in a large litter and this takes the strain off the mum having to rear so many by herself. The little Miniature I mentioned who has recently had the litter of eleven, is looking fabulous and the puppies are only five weeks old. The mum is racing around the farm, as fit and trim as could be, and hasn’t lost an ounce in weight. It’s hard to realize that she had such a big litter so recently, to look at her.
I suspect that if someone is experiencing ill breeding females and weak puppies, then it may well be that they are breeding with bitches whose health is less than suitable for breeding in the first place.
Beverley
A bitch should be a bred a MAXIMUM of 3 times during her life, after two years of age. And after all appropriate health testing for the breed has been completed.
As the bitch grows older, they are more prone to developing respiratory ailments and pneumonia, as well as hereditary defects such as hip dysplasia, an abnormal formation of the hip socket that, in its more severe form, can eventually cause crippling lameness and painful arthritis of the joints.
A bitch that whelps too often will produce weaker puppies more likely to die, and the repeated pregnancies are pretty rough on her, too.
This is up to date information on the subject, not information from 17 years ago as was stated in the story. Knowing what we know now, there is NO reason for ANYONE to be ‘back to back breeding’ unless they are only using the animals as commodities and not the living beings they deserve to be.
Katie
I suspect that your experience may be in toy breed dogs as they do seem to be unusually prone to respiratory diseases such as pulmonary fibrosis, tracheal collapse and chronic bronchitis (1) in old age, but this article advocates breeding dogs being desexed in early middle age so these problems are not relevant to the discussion.
I don’t want to accuse you of line breeding but the regime you outline – of not mating your dog until it’s 4th or 5th oestrus cycle and then missing every second cycle after that – would predispose your dog to cystic endometrial hyperplasia(2) and it is possible that this might, in a dog suffering from immunosupression and inbreeding depression caused by excessive line breeding, produce puppies that are weak. This might explain your view that puppies become weaker in later litters.
Breeders of dogs prone to Hip Dysplasia know how hard it is to select against, and that even the best hip scored parents can frustratingly throw puppies with the condition. No responsible breeder would consider breeding from a dog actually showing clinical symptoms of HD and I’m sure you didn’t mean to imply that you would condone breeding from a dog with preclinical HD.
The reason I raised this topic is that I see many dogs in practice suffering from reproductive problems and I suspect that this may relate to the sort of practices you recommend. I think that you would find that your dogs are more fertile and less prone to fading puppy syndrome if you breed a little earlier and for a shorter period rather than starting late and stretching the breeding period over 3 years.
I would be most interested to read more about your claim that more than 3 litters is deleterious to a bitch. I’m sure that your information is up to date but since you haven’t quoted any references to support your statements it makes it difficult for me to assess your sources. I’m not aware of any such evidence.
It’s a shame that you felt the need to be gratuitously rude and make comments that were not relevant to the facts of the discussion.
1. Helio Autran de Morais, DVM, PhD, ACVIM, RESPIRATORY DISEASES IN OLD DOGS
Proceedings of the 34th World Small Animal Veterinary Congress
WSAVA 2009 São Paulo, Brazil – 2009
2. S. Romagnoli, Infertility in the Bitch, Proceeding of the SEVC, Oct. 17-19, 2008 – Barcelona, Spain Southern European Veterinary Conference
I admit to being puzzled by the experiences related by Katie and I think that it is inadvisable for people to suppose that problems encountered by an individual or in one specific breed or size of breed will necessarily apply to other and/or larger breeds. Statements like this can affect novice breeders and set them off onto the wrong track with their breeding programs.
In the fifty plus years I have been breeding dogs, and the breeds I have bred, which include Scotch Collies, Rotties, Shih Tzu, German Shepherd Dogs,Maltese,and my current breed, the Australian Labradoodle, I have not experienced weakened puppies, pneumonia or other respiratory problems, or reproductive problems other than an occasional caesarian.
It is my view, that it is the individual bitch herself who should determine when she is mated, based on her physical and emotional health, whether or not she lost condition when rearing her last litter, and the ease or otherwise of her labour.
Like women, bitches vary in their mothering abilities, some have easier pregnancies than others, and some enjoy their pregnancies and raising their puppies while others may not.
To sum up, I believe that there should be no ‘blanket’ rule that covers every situation in breeding, and that each bitch should be treated like the individual she is.
Sincerely,
Beverley
Good one Kate.
I also think there should be no blanket rule and that decisions based on when a bitch is best ready to be mated should lay with her breeder and not with mandatory codes, laws or regulations.
Its sad that this is now a subject not many of us can openly discuss and purebred breeders with the ANKC can’t even experiment with and that animal rights propoganda and placing human ideas on fertility and reproduction in our breeding dogs are being moulded by things presented by people who have never bred a dog and/or who have little real idea of what is best for the species.
its a bit of a joke really that thise of us who put our lives into learning about and trying to determine what is best for breeding dogs are over looked by opinions formed from anything other than science.
Concerning Maltese: Can you tell me overall personality changes after they go into heat and do not bread vs after they are bread. Have had dogs all my life and never desexed any females until the last 15 years and have never noticed personality changes in either set of females. Have a friend who has maltese who has had 5 back to back litters and has had very yappy and unpleasant personality now
I’m sure that all the dog clubs have it wrong, I’m sure they don’t look into or research anything or have the best interest of any breed at heart.
The breed clubs may have done research on the adverse effects of natural rather than restricted breeding programs – but they haven’t published it.
I can find no published work which suggests that natural breeding of healthy well nourished bitches causes health problems – indeed if anyone has any data on this I’d love to see the references.
kate… what are you classing as natural breeding?… Natural as in what would happen in the wild without human interference?
In the wild, not every female will breed every season…it is often a convoluted set up influenced, by seasonal conditions, pack sex ratios, and the bitch’s place in the pack hierachy. Pack hierachy is an interesting thing, the dominant, ie alpha female is the one who is allowed to breed, and she does not always let all other bitches in the pack have litters… there-for not every bitch in the pack is breed on every season…
hi folks…
why is this discussion called revisiting back to back breeding…
so far nothing i read actually shows any support for breeding a bitch on every season. The quoted experts discuss either breeding a bitch regularly or the lack of breedng a bitch at all… neither of which meet breeding back to back. Breeding a bitch regularly is not breeding on every season.
I was wondering what everyones views are on how many times a bitch should be bred if needing a c section everytime? or has had more then one? There are certain breeds that scheduled c sections for every litter. Do these same breeding practices of breeding every heat, more then a few times, still for the c section bitch?
I don’t think that any dog that has had a C section delivery should be bred again.
Caesarians HURT and bitches can die under anaesthetic – this is not a normal or natural way for dogs to be born.
If the “Pedigree dogs exposed” documentary showed anything it was that the public has certain expectations of dog breeders. They don’t expect Ridgeback puppies to be euthanased because they don’t have a perfect ridge, or Cavalier KCSs to be bred even though they have life threatening heart and brain problems. I am sure that most reasonable people – if asked – would expect that every dog breed should be of a conformation that enables it to have puppies without a caesarian operation.
Breed clubs could very easily solve the fertility and conformation problems of many dog breeds by banning dogs delivered by C section from the show ring.