But a Breeding Bitch Is NOT Just a Uterus
And here is the first glitch with what was up until now a clear win for back to back breeding. Dams can’t be reduced to their uterus. Of course, her reproductive health matters, but it is only part of a much bigger Health.
Going through pregnancy for dogs is not similar to their ancestor’s experience. Indeed, wolves had much shorter lifespans and fewer heats, therefore they had to breed as often as possible to keep the species alive and strong.
Pregnancy and nursing are sometimes exaggeratedly called a biological war between the mother and the progenies. This is to emphasize how draining and harsh a pregnancy is for the female’s body and support system. This is why, even with the help of modern science, canine pregnancy still kills thousands of dogs every year worldwide.
Back to back breeding is extremely demanding on the mother’s biological resources and energy levels. Therefore, it is also a good idea to skip a heat in order to let her whole body recover perfectly and regenerate before becoming a mother again.
Back-to-back breeding
Let’s start with back-to-back breeding, or breeding without skipping a heat cycle. Traditionally, we thought that bitches needed a “break” between litters for their optimum health. That’s no longer considered best practice, for several reasons.
First, when you look at the reproductive and nursing cycle of a dog and their healing needs, it’s fairly comparable to a human having a baby every 2 years or so. While I emphasize frequently that dogs are not people, I think that as an analogy this can be helpful to some who find initial mental resistance with breeding a bitch as frequently as twice a year.
Next is the effect of progesterone on the uterus. One of the most vocal proponents of breeding back-to-back is well-known reproductive specialist Dr. Robert Hutchinson.
In his seminars, Dr. Hutchinson explains that the progesterone level in the bitch remains elevated for two months after ovulation whether or not she has a pregnancy. This is a critical fact, since progesterone can be inflammatory to the lining of the uterus.
When a bitch cycles and there’s no pregnancy, the uterine lining thickens from the inflammatory effects of progesterone and that can increase the risk of infection (pyometra) and endometriosis. In fact, while most of us think of pyometra as a bacterial disease, Dr. Hutchinson says it’s actually an inflammatory disease, with the bacterial infection being a secondary factor.[1] In Dr. Hutchinson’s own words, the progesterone “hammers the uterine lining for 60-plus days.”[2]
An additional excerpt from the same seminar:
(Dr. Hutchinson also says that bitches should be spayed as soon as they no longer will be bred to help avoid future pyometra and other problems. Research shows that spaying also helps prevent mammary cancer, particularly when done by 4 years of age.)
At the risk of repeating myself once again, dogs are not humans, and while human females shed the lining of their uteruses every cycle, dogs only shed their uterine lining when whelping. As linings stack up, they lose flexibility and elasticity, which can also contribute to fertility problems as that can affect the ability of eggs to attach.
So his advice it to breed your bitches young and breed back-to-back and not to skip cycles unless you have a medical reason to do so.
To add to this, skipping a pregnancy puts your bitch at risk for a phantom, or pseudo pregnancy—a false pregnancy.[3] False pregnancies look just like regular pregnancies, except there are no puppies. Your bitch, however, will gain weight, nest, have enlarged teats, and lactate.[4] But she won’t shed her uterine lining. False pregnancies increase risk of mammary cancers in dogs.[12]
False pregnancies are common in dogs because they provided an evolutionary advantage to wild canid packs—wolves, coyotes, and wild dogs. If a bitch in a pack has a false pregnancy, that means she will lactate and can help nurse the pups of other females.[5]
When should you stop breeding your female dog?
There is no one set age recommendation for when to stop breeding that I have ever been aware of. It’s different for each bitch, and you should consult your repro vet at each breeding to determine with her whether it’s advisable to keep breeding your bitch or if it may be time for retirement.
In general, it’s been my experience that reproductive advice about when to stop breeding has been fairly consistent over the last 20 years: Stop breeding when litter size decreases or problems start to arise. Personally, I prefer to stop breeding BEFORE problems arise. I would rather miss out on having one last litter than risking dystocia or other problems. Adding to this the information from Dr. Hutchinson about trying to start early, breed back-to-back, then retire early, I try to retire my bitches by 4. I’ve had occasion to go a little past that, but that’s the exception not the norm and it was done under the close guidance of my reproductive veterinarian.
Hopefully, there’s enough information in here for you to go talk to your repro vet and decide where your own limits lie.
Should you skip Breeding your females after pregnancy or breed back to back?
If youre new to owning an unspayed female dog, you will definitely want to learn how often a dog comes into heat. You can expect most dogs to go into heat twice a year although you may see differences among breeds and individual dogs.
The onset of heat cycles usually begins when most bitches reach the age of six months, although with larger breed dogs the first cycle may not occur until they are one to two years old. The actual cycle runs approximately two to four weeks with three being the average. The average interval between cycles is six months but can vary from four to 18 months depending on the dog. One of the most recognizable signs of the heat cycle is bleeding from the vulva, which commonly lasts about four to 15 days but can last up to eight more days. Related Articles
Although the heat cycle, or estrus, is referred to as a dog going “into season” there is no specific month or time of the year when dogs will go into heat. A dog can go into heat virtually any month of the year, although there are a few breeds that tend to go into heat only in the spring.