If you have a pregnant pooch, you have probably started wondering how many puppies will be popping out in a few months.
After all, you have to start getting ready for all those adorable pups and buying supplies, so it is important to know whether to expect.
Toward the end of the pregnancy, your vet will likely be able to palpate the mom’s tummy or take an x-ray to determine an “exact” number of puppies in her belly (although it can be easy to miss one of the puppies, so you’ll never know for sure until the little wigglers start coming out). But we’ll try to explain the basics of litter size, so you can start planning.
A pretty exhaustive study of the topic was published in 2011. The researchers analyzed over 10,000 litters representing 224 breeds and found that the mean (average) litter size in this group was 5.4.
However, there’s a fair amount of variation at play. Miniature breeds typically produced litters of 3.5 puppies, while large breeds typically produced 7.1 puppies per litter.
In 2004, a Neapolitan mastiff named Tia became the mother of the largest litter ever documented, when she delivered 24 puppies via Caesarian section.
This is obviously quite the anomaly, as most dogs produce much smaller litters than this. In fact, Neapolitan mastiff litters typically number between 6 and 10 puppies.
A few other notable cases involving huge litters include:
There are a number of different things that can influence the size of a dog’s litter, and we’ve detailed some of the most important ones below. It is difficult to empirically determine how much these various factors influence litter size, and it is likely that the various factors influence each other to some degree.
A dog’s breed is one of the most important factors influencing litter size. Simply put, larger breeds produce larger litters. That’s why Shih Tzus, Pomeranians and Chihuahuas have litters typically ranging from one to four puppies, while Cane Corsos, Great Danes, and other giant breeds often give birth to eight puppies or more.
Within a given breed, larger individuals typically give birth to larger litters. For example, a 45-pound Labrador retriever may produce a litter of only five or six puppies, while an 85-pound Lab may produce a litter of 10 or more.
While dogs typically remain fertile for their entire lives, they are most fecund during early adulthood – usually between 2 and 5 years of age. However, a dog’s first litter is generally smaller than subsequent litters.
Dogs in good health are more likely to produce larger litters, and they’re also more likely to produce healthy puppies. In fact, it is imperative that any female slated for breeding trials be in perfect health to ensure she and the puppies will survive the birthing and whelping process.
Diet likely has a strong influence on litter size. Some breeders contend that dogs who are fed a high-quality commercial food that is supplemented with high-protein foods (such as meat and cheese) produce larger litters than dogs fed substandard foods or those fed only high-quality commercial foods (with no supplemental proteins).
The smaller a dog’s gene pool is, the smaller her litters will tend to be; conversely, dogs who come from more diverse backgrounds tend to have larger litters. This means that dogs from lines that have been inbred extensively will slowly develop smaller and smaller litters.
Dogs are all individuals, who vary in countless ways; sometimes, this can include litter size. This is very difficult to predict, but dogs who produce large first litters and likely to produce large second and third litters, assuming all other factors remain constant.
Note that most of these traits relate to the dam (female) rather than the sire (male). However, the sire does have some influence on the litter size. His breed, size, health, age and individual genetic makeup will partially determine the size of the litter he sires.
Some females can produce multiple litters within a 12-month period. It just depends on the dog’s natural cycle, body condition and the desires of the breeder. A handful of canines will cycle quickly enough to produce three or four litters in a year, but most dogs only have two cycles per year, spaced about six months apart.
But, breeding a female twice in the same year is frowned upon by many breeders. Doing so is very hard on the mom’s body, and many believe that it will result in a decline in the total number of puppies produced by a dog over her lifetime. Accordingly, many will allow their dog to produce a litter, and then give her a breather during her next heat cycle. This essentially means that they’ll produce one litter per year.
However, other breeders see no reason to avoid breeding dogs in heat, as long as they are healthy and in good physical condition.
In fact, breeders of this mindset often argue that because fertility decreases with age and most dogs will be six months older with every heat cycle, you can produce more puppies over the course of a female’s life by breeding in back-to-back heat cycles during the prime reproductive years of a dog’s life.
Theoretically, a single female dog could produce quite a few litters in her lifetime. Assuming that a female produced two litters per year starting at 1 year of age and continued doing so until she was 8 years of age, she’d produce 14 litters over her lifetime.
As previously mentioned, litter size varies based on a number of factors, but for argument’s sake, we’ll assume that she has about five puppies in each litter. That means that – again, theoretically — a single dog may be physically capable of producing upwards of 70 puppies(!) over the course of her life.
However, this would be madness. Breeding a dog this many times would almost certainly compromise her health, and this type of pedal-to-the-metal breeding is more characteristic of puppy mills and unscrupulous breeders than conscientious breeders who value the well-being of their pups.
Additionally, some of the registration organizations will not allow you to register an unlimited number of litters. For example, the Kennel Club of the UK will only allow you to register up to six litters from a single mother.
As mentioned earlier, a dog’s size – and therefore her breed – is probably the most important single factor that influences litter size. Larger dogs produce larger litters, so it stands to reason that breeds with larger average size will produce more puppies than breeds with smaller average body size will.
Simply put, Great Danes will usually produce larger litters than Chihuahuas will. We can’t find a reliable study that has sought to determine the most fertile breed, but it is surely one of the largest ones, such as one of the mastiffs, Irish wolfhounds, or Great Danes.
However, it is a bit more difficult to determine which breed will usually produce the most puppies over the female’s entire lifetime. This is partially due to the fact that small dogs routinely live much longer than large breeds do. A Pomeranian may, for example, live to be 15 years of age, while Irish wolfhounds usually only live for about half as long.
So, while the Pomeranian’s litters are likely to be much smaller than those of a wolfhound, the Pomeranian will have the chance to produce many more litters over the course of her life.
Additionally, small breeds tend to experience their first heat at a younger age than larger breeds do (sometimes an entire year earlier). They also tend to cycle more quickly, which also makes them more likely to produce more litters than larger breeds.
Pregnancy usually lasts about 58 to 68 days in dogs. This can vary based on a number of factors, including the female’s age and health, as well as her breed. It can also be difficult to determine the exact time of conception, which can introduce a bit more wiggle room into this figure.
But for most purposes, you can figure that your dog will be pregnant for about two months, or perhaps a bit longer.
Unfortunately, there aren’t many early signs that will indicate that your dog is pregnant. In most cases, you’ll have to wait about three to four weeks before the signs of pregnancy become apparent.
Some of the most common signs that indicate pregnancy include:
Of course, if you suspect (or hope) that your dog is pregnant, the best way to know for sure is to make a trip to the vet. Most breeders recommend visiting the vet about two to three weeks following mating anyway.
By the 21st day of your dog’s pregnancy, your vet should be able to verify that she’s pregnant via a blood test. It is also possible to start visualizing the puppies via ultrasound around this time (perhaps a few days later).
There is also a small window of time – between the 28th and 35th day of pregnancy – when your vet can safely palpate your dog’s abdomen. This will allow him or her to verify that there are puppies in her uterus. Note that this is a very delicate procedure, which should not be carried out by those who haven’t been trained to do so. Rough handling of the developing babies may injure them or trigger a miscarriage.
By day 45, your vet can X-ray the mother to see the developing babies. This will not only allow the vet to count the number of puppies present, but to inspect their bone structure and note any abnormalities.
While most dogs are excellent mothers for their second, third and subsequent litters, first-time moms often have a bit of trouble figuring things out. Accordingly, you’ll want to keep a very close eye on first-time moms to make sure everything goes smoothly and that she does all of the things a good mom should.
For example, you’ll want to be sure that all of the puppies are finding nipples and getting enough food to keep their bellies full and bodies warm. You’ll also want to make sure that the mom remains healthy and happy throughout the process – if she starts having health-related or emotional problems during the whelping process, the puppies are likely to suffer.
Fortunately, as mentioned earlier, a dog’s first litter is generally pretty small. For example, dogs from breeds who typically produce litters of five puppies may only produce one or two for their first litter. This makes it much easier to keep an eye on everybody and nip problems in the bud.
Large litters may seem like a beneficial adaptation for any species, but in practice, things are rarely so simple.
In fact, litter size (or clutch size, as it’s called in egg-laying species) is a very important factor in the evolution of animals. Most of the time, evolutionary pressures result in the most appropriate litter size for a species’ life history and survival strategy.
For example, some animals – humans, elephants, and hippopotami are a few of the best examples – typically give birth to very small litters, consisting of one or two individuals. These animals live long lives, have high survival rates and typically invest a lot of resources and effort into each offspring.
At the other end of the spectrum, other mammals produce huge litters of tiny babies. For example, the tailless tenrec – a bizarre insect-eating mammal from Madagascar – usually gives birth to about 15 babies, but litters numbering more than 30 have been documented. These animals have high mortality rates, live relatively short lives, and invest relatively few resources in each individual offspring.
Dogs fall somewhere between these two ends of the spectrum, as the average litter size across all breeds is about five. They invest a moderate amount of resources in each offspring and live moderately long lives.
The various processes shaping litter size also influence the number of nipples that a species has. As a general trend, the maximum litter size usually matches the total number of nipples present.
Humans are a great example: Most mothers give birth to a single baby, although twins aren’t all that uncommon. This helps to ensure there are enough nipples to go around, and it even provides some protection in the case that some of the mother’s nipples fail to function properly.
The one-half rule is pretty reliable for dogs too. Most dogs have eight to 10 nipples, and the average litter size is about five.
But understand that this is a statistical correlation, not a way by which you can predict the number of puppies your individual dog will have. So, stop counting your dog’s nipples and just scratch her behind the ears like she wants. She’s a good puppy-wuppy, yes she is.
I once had a relatively small chocolate lab who produced a litter of 9 and a litter of 10, which proved to be quite the handful. I can’t imagine having to care for 15 or 20 newborn puppies wiggling around in a whelping box. In those kinds of situations, puppy milk replacement formulas and feeding devices are pretty essential for keeping the full litter alive (and not driving poor mom out of her mind).
Tell us about your puppy litter experiences. Have you ever had a dog that produced a huge litter? How did the whelping process go? Let us know all about it in the comments below!
Ben is a proud dog owner and lifelong environmental educator who writes about animals, outdoor recreation, science, and environmental issues. He lives with his beautiful wife and spoiled-rotten Rottweiler JB in Atlanta, Georgia. Read more by Ben at FootstepsInTheForest.com.