by C.A. Sharp
August 2013
Birds do it, bees do it,
Even educated fleas to it…
– Cole Porter
There is nothing more basic to biology than reproduction. Without it, no species will continue to exist. The Biblical admonition to “be fruitful and multiply” is a biological imperative. One-celled organisms do it by dividing, a process which multicellular organisms have incorporated to grow or replace lost tissue. The more primitive multicellular life forms “bud”, growing small versions of themselves which ultimately separate from the parent and go their own way. Some plants have their own versions of budding but can also produce offspring through pollination, others only reproduce via pollination though in some species both parents may be the same individual. (Plants are kinky.) With rare exceptions, animals require a male and a female to reproduce.
Dogs are animals and, as a species, are enthusiastic about reproduction. Even though they have long been domesticated they can and will form self-sustaining populations with little or no assistance from us, as attested by populations of feral, pariah, and street dogs around the world. But sometimes things go wrong and breeders of purebred dogs may not always pay sufficient heed to the lessons of biology.
The miracle of technology
Veterinary medicine has made great strides over the past couple decades. Things that were once a death sentence can now be treated and supportive care can extend lifetimes. Reproductive veterinary medicine offers services that would have seemed like science fiction when my first litter was whelped in the mid-1970s. No one would question the need to treat disease and save lives, but when it comes to enabling a dog that cannot or will not breed naturally to reproduce, should we? Exhibit A is the Bulldog.
Remember that the ancestor of every dog, no matter what shape or size, was the 100% Natural Dog: the wolf. A wolf’s body plan is the one that worked in nature and most wild members of the dog family are pretty much that same shape, though size, color, and coat vary. Our domestic dogs have a sizem shape, coat, and color range far beyond that of all of the other members of the genus Canis put together. The Bulldog is one of the most extreme, with a huge head on a short, very broad body with proportionally small hips. This body morph prevents the great majority of Bulldogs from being able to breed or whelp naturally; without modern veterinary medicine to assist the breed would likely be extinct simply because it can’t reproduce.
While few other breeds face the Bulldog’s reproductive challenges there are still instances, likely in every breed, where for some reason the dog is unable to reproduce. If the dog is ill, it should be treated but “fixing” things via veterinary intervention to enable a dog that otherwise couldn’t reproduce to make puppies risks perpetuating something that strikes at the very core of breeding: The ability to, well, breed.
C-sections are a fact of life for Bulldogs and their breeders, but they have become a fairly common veterinary practice. Certainly if the lives of the bitch and the litter are at risk, a C-section should be performed but it should never be performed for convenience sake and if it is a necessity the breeder needs to ask the question “why?” and carefully consider what the answer means to her breeding program.
The Do-It-Yourself Method
For all but a portion of the past century dogs reproduced with at most minimal human involvement. People may have made the decision on which male and female to cross and taken steps to make sure some no other males got the chance to make their own contribution. Dogs who couldn’t or wouldn’t generally didn’t. A non-breeder might continue to have value for whatever work was its lot but most people weren’t likely to go to great lengths to get it bred assuming there was even a way in which that it might be accomplished.
Mating seems easy enough: Insert Tab A into Slot B. Both parties are normally more than willing to comply. The dog can then go his merry way hoping another willing partner will turn up. But it doesn’t end there for the bitch. Females must carry the litter for nine weeks, deliver a litter of vigorous puppies, nurse them and raise them to weaning. This involves not only the reproductive health but the innate behavior of both parents. Anywhere along the way from first introduction to a weaned litter things can go wrong because of something lacking in one of the parents.
Artificial insemination is a great boon to breeders and in some ways a benefit to dogs. It is easier, safer, and cheaper to ship frozen semen than to ship a dog. The stress of travel and being in a strange place, possibly away from anyone the dog knows, is eliminated. There may also be a lowered risk of transmitting doggy STDs depending on the method used and the specific disease. A win-win right? Not necessarily if it’s an end-around problematic breeding behavior.
Breeding practices can be possible cause of assorted breeding failures if mating choices result in ever-increasing levels of inbreeding. Inbreeding depression is evidenced by reproductive failures, including sterility, shortened longevity, impotence, low libido, poor mothering behaviors. reduced litter size and high infant/juvenile mortality.
When the flesh is strong but the soul isn’t willing
Breeding and mothering behavior is every bit as important to accomplishing the task as reproductive physiology. Every animal species has behaviors to signal willingness to mate. Mothering behaviors vary widely from intense to non-existent, but among mammals, Mom always has an important role to play and a suite of behaviors that enable her to do it properly. Because puppies are born requiring a lot of maternal attention, their dam’s maternal behavior is crucial to their well-being and even their survival. Whenever an individual lacks appropriate mating behaviors a litter may not happen and poor mothering puts the litter at risk. This behavior should be innate and if any individual consistently exhibits abnormal reproductive behavior continuing to breed it risks passing it on to offspring.
There’s an old joke that goes: A woman has to be in the mood, a man has to be in the room. For bitches “in the mood” means standing heat. Male dogs, like men, just want to be in the room when the time arrives. Disinterest by a male or strong reluctance by a female for breeding can occur for a number of reasons. An experienced stud will know when a bitch is ready and may be disinterested if he knows she is not. If a dog is unwell it may not want to breed. If the male is well down in his home pack pecking order, he may be reluctant to breed when he can hear/see/smell his superiors. If a bitch is particularly dominant she may not accept a subordinate male. Occasionally, a bitch will refuse a male that is close kin. And there are probably other reasons as well. But if a dog (male or female) is healthy it should be willing to breed. A male should not lack interest in a female who is obviously ready and willing. A female who is ready should not make more than token objection to the male. There should never be violently aggressive behavior toward the prospective mate. Seriously violent behavior at mating is unacceptable. If any of these other behaviors happen more than once and with different prospective mates and no health or other behavioral reason can be found, it is a serious fault in a breeding animal. If there is any question, have the dog checked by a reproductive specialist but the goal should be finding out what went wrong if you can, not getting the dog bred at any price.
Poor mothering behavior can take many forms, including disinterest in the litter, failure to clean the puppies or open the birth sac, damaging puppies through clumsiness or inattention, or even attacking or killing her unweaned pups. A maiden bitch may make mistakes due to inexperience. An underlying illness, reproductive or otherwise, may interfere with proper behavior. A bitch may sense that something isn’t right with a particular puppy and push it aside. Too much noise or activity around the whelping box or if other dogs are active nearby these distractions might interfere with a brood bitch’s behavior toward her litter. But if bitch and litter are healthy and she has a quiet and private place she should be able to whelp and rear her litter with no more than food and cleaning services from the resident humans.
A glitch in the system
Physiological breeding dysfunction and defects are perhaps better recognized. Some infections and diseases can interfere with reproductive function in both sexes. If infections invade the genital tract they may be transmissible to mates. If they cannot be treated the dog must be removed from further breeding. Diseases that interfere with reproduction might or might not have a genetic basis. If they do, as is sometimes the case with thyroid disease in females, the affected individual should not be bred and while its disease should receive treatment, it’s short-sighted to use the treatment to enable you to breed the dog.
In males, perhaps the most recognized reproductive defect is cryptorchidism or retained testicles. A single missing testicle is called “monorchidism” by dog breeders. Dogs in which neither testicle descend are sterile but those with one descended are capable of breeding. It should be kept in mind that every major dog showing body considered cryptorchidism a disqualifying fault. Other male reproductive issues include testicular atrophy, low sperm count, and lack of motility.
Testicular atrophy in old dogs is normal, but if it occurs in a young male or one in his prime the cause needs to be investigated. Diseases, medications, hormonal imbalance, and excess heat are among potential causes. In rare cases it may be due to an autoimmune reaction which probably means there was a genetic risk. Any cause that has a genetic basis should be reason not to continue breeding the dog.
Problems with sperm production, ranging from none to too few to sperm than can’t adequately get from point A to point B, may be due to infection or other disease, injury, age, medication, and physical defects in the male reproductive system. Old age, injury, and medication are not a genetic concern. Physical defects very likely could be and should be considered a reason to withdraw the dog from breeding.
Females have their own set of physiological issues. They may have irregular or no heats, or be unable to conceive. Thyroid disease or other hormonal imbalance may prevent breeding. If a female is unable to conceive or carry a litter due to a physical or hormonal defect she is not a good breeding candidate even if veterinary medicine can correct or get around the problem.
C-sections are not relatively common. In some breeds wth extreme body shapes they can’t be escaped. But with normal canine body morphology, without gross exaggeration of the skeletal structure or size of the body, a bitch should be able to whelp without human assistance. However, if medically required a C-section should be performed for the sake of the bitch and her puppies. Whenever this happens the breeder should closely examine the reasons the C-section was necessary and discuss those with her vet. If the need for surgery arose from a reproductive defect in the bitch, she should not be bred again. A bitch who cannot naturally carry and deliver a litter should not be bred further. C-sections should never be used as a matter of convenience to the breeder.
Litter size is largely determined by the bitch. She will release a certain number of eggs. If there is sperm there at the proper time, they will be fertilized. There are many reasons why you might get a very small litter ranging from reproductive issues in sire or dam, underlying health issues in the dam, or timing of the breeding. Litters may be aborted or fetuses reabsorbed due to genetic defects, hormonal imbalance, acquired diseases, or toxic exposures, including medications, during pregnancy. Diseases and toxicity and be avoided or treated. Hereditary diseases with known inheritance or with screening or DNA tests – as with Pelger-Huet Anomaly and the bob-tail gene,both of which can cause fetal reabsorbtion – can be avoided through mating choice and/or screening. Any hormonal imbalance with a genetic basis, like thyroid disease, should eliminate a bitch from breeding.
The female “system failures” don’t end at whelping time. A bitch may have difficult delivering her puppies, have an Inadequate milk supply or develop mastitis. These can occur for a wide variety of reasons. If a bitch has difficulty whelping or inadequate milk with more than one litter, she may not be a candidate for further breeding. Some bitches are prone to mastitis, a painful infection of the mammary glands during lactation which requires that the puppies be removed from the dam which causes considerable extra time and veterinary bills.
Back to basics
A lot of breeding dysfunction might be avoided if we relied less on technology to fix things and more on making sure nature can take its course. Young dogs of either sex should be mated to experienced older mates to make sure they actually can mate naturally. If there are any difficulties that might be due to circumstances or inexperience, give it another try. But if a dog can’t or won’t figure it out on his or her own by that point, it isn’t a good breeding candidate no matter what its other virtues.
Bitches must be good moms. Breeders should make sure the bitch has a clean, dry quiet place to whelp with a proper whelping box and be around in case of emergencies. But interference with the process because the bitch can’t deliver and care for her puppies on her own raises serious questions about whether or not she ought to be bred again. As would a failure on the bitch’s part to nurture her growing litter.
As I said at the top of this piece, there is nothing more basic to biology than reproduction. Any dog that cannot or will not successfully mate naturally and, in the case of a bitch, whelp and rear her litter without more than routine husbandry or medical intervention should not be bred.