Breeding for Good Whelpers: The Trait We Forget to Select For

Quick answer: A good whelper is a dam who goes into labor on her own, delivers her puppies without help, and looks after them properly once they’re on the ground. Almost nobody breeds for this on purpose.

Part of the reason is practical, because you can’t find out how she’ll do until you’ve already bred her.

The other part is that modern veterinary care covers for the dams who can’t do it, so the trait quietly disappears from our decisions without anyone choosing to ignore it.

We select for a lot of things. Hips, elbows, eyes, hearts. Genetic panels. Coat, size, structure. Working ability, drive, biddability, nose. Temperament, which everyone agrees is the most important thing right up until the moment a beautiful dog comes along.

People get criticized, fairly often and sometimes fairly, for breeding purely for looks. But here’s a question that almost never comes up in those conversations: how many of us are deliberately selecting for a dam who can give birth and raise her own puppies?

Not many. And it’s worth talking about why.

What does it actually mean to be a good whelper?

It’s not one trait. It’s a bundle of them, and they can fail independently.

Labor that starts and keeps going

The uterus has to contract effectively, on its own, and keep contracting until the last puppy is out. When it doesn’t, that’s called uterine inertia, and it’s the single most common reason whelpings go wrong.

Depending on the study, it accounts for somewhere between 55 and 70 percent of difficult births. One review of 530 cases of difficult labor found that about 42 percent were down to maternal causes, mostly inertia, while litter size was the main problem in only 16 percent.

Calcium plays a real role here, and if you haven’t read it yet, my guide to calcium during and after whelping covers how to use it and how not to.

Structure that lets puppies out

Whether her pelvis is roomy enough for the puppies she’s carrying. This is the part most people think of first, and it’s what comes up whenever flat-faced breeds get discussed. It isn’t only their problem.

Milk that comes in, on time and in enough quantity

A dam who delivers beautifully and then has nothing for 36 hours is not a good whelper, whatever else she did right. Some of this is on you rather than her, since a nursing dam’s calorie needs climb dramatically, and underfeeding her can look exactly like a milk problem.

The behavior that follows

After each puppy is born, she needs to break the sac, clean the puppy’s face, and lick it hard enough to get it breathing. A delay here kills puppies.

Then she needs to keep them warm, stimulate them to eliminate, let them nurse, and not lie on them.

She also shouldn’t be so intense about it that she can’t leave the box to eat.

A dam can be excellent at three of these and useless at the fourth. That’s part of why “she’s a good mother” is such a slippery thing to record.

Why don’t breeders select for this?

Three reasons, and none of them are anybody’s fault.

1. You can’t test for it. There’s no certification, no panel, no rating. There’s no OFA number for whelping. You find out how a dam whelps by breeding her, so you learn it too late to use it.
   

2. It only shows up once or twice. Most dams in responsible programs have two to four litters in their lives. That’s a tiny sample. A dam who had one hard whelping and two easy ones hasn’t given you a clear answer, and you’d need her daughters and her sisters to make sense of it.
   

3. We fix it, and then we forget it happened. This is the big one.
   

Has veterinary care removed the pressure to whelp well?

Yes. And I don’t think that’s controversial, even though it sounds like it should be.

In a wild population, an animal who can’t deliver her own young doesn’t leave descendants. Neither does one who won’t clean her newborns. That’s brutal, and it’s also the only reason those traits stayed intact in the first place. The ability to give birth and raise young got selected for automatically, constantly, and for free.

We removed it. Not on purpose, and not because anyone made a bad decision. Emergency C-sections save dams and litters that would otherwise be lost. Oxytocin and calcium restart stalled labors. Tube feeding and incubators keep puppies alive when a dam won’t mother them.

Every one of those is good veterinary medicine and I’d use all of them without hesitating.

But look at what happens next. The dam who needed the section recovers, raises a nice litter with our help, and we keep a lovely puppy out of her. That puppy carries whatever her mother carried. Nobody wrote “required intervention” in the column that gets weighed against her, because there isn’t one.

This isn’t a fringe worry, and breeders aren’t the only ones raising it. Vets are arguing about it among themselves. One review asked a blunt question: when a practice offers scheduled C-sections, is it helping breeders keep producing dogs that can’t give birth on their own?

The Royal Kennel Club in the UK has gone further. It won’t register a litter from a dam who has already had two litters by C-section, unless you get permission in advance and have a documented health reason.

We also have numbers on how big the gap is. A survey of UK breed club members looked at 151 breeds, more than 13,000 dams and 22,000 litters. In three breeds, more than 80 percent of litters were born by C-section. In seven breeds, not one litter was. That’s the spread.

The part I find most interesting isn’t the flat-faced breeds, which everyone already argues about. It’s that one breed with a perfectly normal muzzle came in at 60 percent. The researchers pointed out something worth sitting with. That breed was already known to have a pelvis shape that makes delivery hard, but the pattern in their data suggested the uterus wasn’t contracting properly either. So this isn’t only about heads and hips. Labor itself can fail, in dogs who look completely ordinary.

Is whelping ability actually heritable?

Some things a dog gets almost entirely from her parents. Other things are mostly down to luck and circumstance, and hardly get passed on at all. Most traits sit somewhere in between.

We can measure where a trait sits on that range, livestock breeders use this all the time. The number they use is called heritability, and it answers one question: if I breed the best animals I’ve got, how much better will their offspring be?

A high number means a lot better, and quickly. Pick good parents, get good offspring, and a herd can change noticeably in two or three generations. A low number means a little better, slowly.

You still gain ground each generation, but you gain it in small amounts, and you need a lot of animals and good records before you can see that anything has changed at all.

Nobody has measured that number for whelping itself. But plenty of numbers exist in dogs, and some of them sit right next door to what we are talking about here.

Almost all of them come from guide dog breeding colonies. Those programs keep records on hundreds of litters across many generations, which is exactly what this kind of measurement needs. Here's some of what they've found:

• Litter size scores around 0.24 in Labradors and 0.19 in German Shepherds

• Puppies still alive at 14 days scores around 0.28 and 0.25 in the same two breeds

• Hips score much higher, between 0.41 and 0.76 depending on breed. Guide dog programs have been selecting on hip scores since the 1980s and have measurably better hips to show for it
  

That last one is the important one. It's proof the whole approach works in dogs. Not in cattle, not in pigs. In dogs.

There's one more worth knowing about. Researchers can separate how big a puppy is because of its own genes from how big it is because of its mother's genes, and the mother's own contribution has been measured at around 0.22 in one Labrador colony and higher in others.

Puppy size is one of the main reasons births go wrong. So there's already a measured genetic contribution from the dam to something that directly causes hard whelpings.

What nobody has published that I can find is a number for whelping ease itself, or for how good a mother she is. The closest thing we have is puppies alive at 14 days, and that's a rough stand-in at best, since a puppy can die for reasons that have nothing to do with her.

And notice where all these numbers came from. Big organizations that keep detailed records over decades. That's not a coincidence, and it isn't a knock on anyone. It's the whole problem in one sentence. The measurement is possible. What's missing is the records, and we can fix that.

Here's the rest of what we have to go on.

Breed differences are large and consistent

The C-section and dystocia (difficult whelping) rates above vary enormously between breeds that are kept and cared for in much the same way. That points to genetics. What it doesn’t tell you is how much difference is left between dams inside any one breed, and that’s the thing you’d actually be choosing between. In a breed where nearly every dam needs help, there may not be much left to pick from.

Vets already treat this as partly inherited

When veterinary references list what causes a uterus to stop contracting, one item on the list is that the dam inherited the tendency. The rest of the list is hormones, calcium, a litter too big for the uterus to handle, and her general health. So this isn’t a fringe idea coming from breeders. It’s in the standard texts.

One veterinary lecture on C-sections says it about as directly as you could ask for: if a dam needed a section, watch her daughters for the same trouble, and be willing to change what you select for.

Other animals have been measured, and choosing better parents worked

Cattle breeders have scored bulls for decades on how easily their daughters give birth. The score is low, so progress is slow. They made progress anyway.

Pigs are the closer comparison, because a sow has a whole litter at once. How good a sow is with her piglets scores very low, roughly 0.1 out of 1. That means on any given day, most of what you’re watching is circumstance rather than genes. It still worked. One group of pigs was bred for piglet survival and another group wasn’t, and years later the difference showed up in how they behaved: first-time mothers from the group nobody had selected were far more likely to crush their piglets when they shifted position.

So a low number doesn’t mean you’re stuck. It means progress is slow and you have to write things down and sometimes make hard decisions.

Breeding hard for one thing can change mothering without you meaning to

Sheep breeders selecting for leaner meat ended up with ewes and lambs that behaved differently at birth. Nobody chose that. It came along with the thing they were choosing. If you’re breeding hard for one feature, whether that’s a head, a coat, a color, or a working trait, it’s worth asking what else might be coming with it.

What does the research say about mothering behavior specifically?

More than you’d expect, and most of it is recent.

Researchers watching guide dog mothers found that they differ from each other in how they handle a litter, that each mother stays fairly consistent from week to week, and that this isn’t just a matter of her breed, her litter size, or how many litters she’s had. It’s her. In a follow-up study, how a mother handled her puppies predicted whether those puppies later made it as guide dogs.

Separate work with German Shepherds in Sweden found something similar. How much care a puppy got in its first weeks showed up in its temperament when it was tested at about 18 months old.

Put those together and you get three things. Mothers differ from each other. Each mother is fairly consistent. And it matters to the puppies for years afterward.

The clearest statement anyone has made on this comes from a 2020 veterinary review. It said genetics probably plays an important part in how a dam mothers, that this is worth paying attention to when you choose breeding stock, and that taking poor mothers out of a program looks like a sensible thing to do.

It added one caution I want to repeat, because it’s easy to get wrong. Dams generally give less care to a puppy that’s sick or fading. That’s normal, not a failure. Judge her on the healthy ones.

There’s also a survey of Australian breeders worth mentioning. Maternal care was one of four things those breeders said they considered when picking a dam. But plenty of them didn’t seem to realize how much it mattered. That matches what I see.

How do you track this in your own program?

You almost certainly keep whelping notes already. The change is small. Write down the things that will still make sense to you three years from now, and then actually look at them before you decide which puppy to keep.

I've put together a free record sheet you can print and keep in the whelping box, along with a summary page for tracking a dam across all her litters and her daughters after that. You can download it here. It covers everything below and a few things that are easier to fill in than to remember.

For each whelping, write down:

• Did labor start on its own, and how long did it take from the temperature drop

• Total whelping duration, and the longest gap between puppies. This is much easier to judge if you know how many puppies to expect, which is one of the better arguments for an x-ray before whelping (click for a discussion about safety as well).

• Did you intervene, and how. Repositioning a puppy is different from calcium, which is different from oxytocin, which is different from surgery

• If she got a C-section, was it planned or an emergency, and what was the reason

• How long until milk let down

• How many puppies she cleared and stimulated herself without you stepping in

• Puppies alive at 24 hours and at 72 hours

• Any lying on puppies, ignoring puppies, or refusing to settle in the box

• Whether she’d leave the box to eat and eliminate

For the dam overall, keep a running note across litters. One event is noise. Three litters is a pattern.

For the program, this is the part that matters most: track it in her daughters. A single dam’s record can’t tell you whether you’re looking at genetics or circumstance. Her daughters and her sisters can.

When is a hard whelping not a genetic problem?

Often. Which is exactly why you can’t treat one bad night as a verdict.

A single oversized puppy in a small litter is bad luck. A puppy coming out sideways is bad luck. A very large litter that wears the uterus out is a physical problem, not a character flaw. First litters are often rougher than the ones that follow.

Where she whelps matters more than people think. A dam giving birth somewhere noisy, unfamiliar, or stressful has a harder time of it. There’s also evidence that dams who had a hard labor spend more time lying with their puppies afterward, which sounds like devotion but is probably exhaustion and soreness.

In every animal anyone has studied, pain makes a mother worse at mothering. It's worth knowing that she has her own pain relief built in, which is a good part of why dams eat placentas. If she’s sore and worn out, what you’re watching isn’t who she is.

There's one situation where this goes badly wrong, and it's worth knowing about before you judge any dam harshly. A dam coming out of anesthesia after a C-section missed the entire birth. She never smelled or tasted the fluids that tell her brain these are hers. In one study, dams whose puppies had been washed and whose placentas were taken away rejected those puppies for 36 hours. When the researchers rubbed the puppies with the saved placentas and fluids, the dams accepted them straight away.

Read that again, because it's the whole point of this section. Those dams looked like terrible mothers. They weren't. They were missing a smell. If you ever have a dam who won't take her litter after surgery, that's the first thing to fix, and it's another reason to ask your vet to save the placentas.

Her own upbringing counts too. In one study at a large breeding facility, dams who had been born and raised there had easier births and nursed more in the first day than dams who were brought in from somewhere else. Being in a place she knows makes a real difference.

So before you write anything in her permanent record, ask what else could explain it.

What do you actually do with the information?

Not what you might be bracing for. I’m not suggesting you take a good dam out of your program over one hard whelping.

I’m suggesting you give whelping ability the same weight you’d give anything else you select for. It counts, but it isn’t the only thing that counts.

In practice that means a few things. When two puppies from a litter are close on everything else, let the whelping record break the tie. When you’re looking at an outside stud, ask how his mother and his sisters whelped, because his daughters will whelp too.

When a dam needs help twice for the same reason, take it seriously instead of calling it bad luck twice. And when a dam gives birth easily and mothers well, understand that she has just handed you something you can’t find out any other way.

Nobody has to solve this alone or all at once. But if enough of us start writing it down and weighing it, the trait comes back into view. Right now it’s invisible, and invisible traits slip away from us.

Frequently asked questions

Should I stop breeding a dam who needed a C-section? 

Not automatically. It depends on why. A malpositioned puppy or a single oversized puppy tells you very little about her. Primary uterine inertia, or a pelvis that couldn’t pass normally sized puppies, tells you more. Talk it through with your reproductive vet and look at the reason, not the procedure. Note that some registries restrict how many litters a dam may have by C-section, so check your registry’s rules before you plan another breeding.

Is uterine inertia inherited? 

Several different things cause it. Standard veterinary references list an inherited predisposition as one of them, alongside hormonal factors, calcium, litter size, overstretching of the uterus, and the dam’s general health. Calcium is the one you have the most control over, and I’ve written about how to use it during and after whelping. There’s no genetic test for inertia. If it happens more than once in a dam, or shows up in her close relatives, treat that as meaningful.

Can you select for mothering ability if it barely passes down? 

Yes, though slowly. Cattle and pig breeders do it with traits that pass down just as weakly. It means you need good records and several generations before you see movement. It doesn’t mean the trait is stuck where it is.

How many litters do I need before a dam’s whelping record means anything? 

Two or three tells you something about her. Her daughters tell you something about your line. One litter is a data point, not a pattern.

Doesn’t intervening make me a bad breeder? 

No. Intervene every single time it’s needed. A dam in trouble at two in the morning needs help, not a philosophical position. The argument in this post is about what you record and what you weigh afterward, not about withholding care.

Where to go from here

Start with the free Whelping and Mothering Record. Print a set before your next litter is due. Nothing in this post costs you anything until you have records worth reading.

If you want to get better at reading what’s actually happening during a whelping, and at knowing when to step in versus when to wait, that’s what these cover in depth:

• Breeder Basics: Whelping if you want to start with the fundamentals

• Breeding & Whelping Your Litter Bundle for the full picture, from timing the breeding through delivery

• Canine Nursing & Weaning picks up where this post leaves off, covering milk, let-down, and the weeks that follow

And if what you really want is a second set of eyes at three in the morning, the Whelping AI Companion Suite is built from these same materials to help you think through what’s happening and what to do next.

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