Dogs, as are most carnivores, are physically designed to have litters of two or more puppies. They are physically designed to handle larger litters. A female dog can have as many as ten nipples and her uterus is larger, making room to carry a number of puppies.

This tendency goes back to the days when dogs were wild. As carnivores, they led hard lives and many pups did not live to become adults so it made sense to have larger litters. As with all things, there are exceptions to the norm and dogs can have only one puppy.

Can dogs just have one puppy?

Yes, dogs can have only one puppy, but this doesn’t happen often. The average litter size can be anywhere between two and ten, with some litters being even larger. The bigger the breed of dog, the larger the number of puppies they have.

This makes sense considering they have a larger uterus and can carry more. There have been cases of even larger litters being whelped. When a dog has only one puppy, the puppy is called a singleton. The cause can be due to a number of reasons.

When only one puppy is born, this can create problems both during birth and afterward. The problems can be avoided with the right knowledge in advance.

Knowing how many puppies your dam is carrying will help you prepare for the event and create an environment where both mother and puppy are happy and healthy.

What are the chances of a dog having just one puppy?

The chances of having only one puppy are approximately 6.4 percent. The chances are higher for litters born through artificial insemination, inbreeding, or those born in the fall.

This may seem like a small chance but it isn’t any smaller than a dog having an extra-large litter of more than 15. 

The chances of having only one puppy are dependent upon many factors. These include the ages of the parents, the health and diet of the mother and whether this is the first litter or not.

Solo births are more common in first or second litters. It is also more common for a female to have a solo birth if she had previous ones. Scottish Terriers are a breed that is often prone to singleton births.

Are Singleton puppies bad?

Singleton puppies aren’t bad, but they can come with many problems, both physically and socially. A solo puppy will often be larger than those from a litter and this may create a problem for the mother, especially if she is a small breed.

Whelping is started when the puppies have run out of enough nutrition inside the womb. They send out a chemical signal that starts the dilation process.

When there is only one puppy, there may not be enough of this chemical to initiate the dilation, or the dilation may start and then stop. While singleton puppies can be born naturally, often it is necessary to have a c-section performed.

The mother’s milk is another thing that is chemical-based. For some mothers, there isn’t enough of a message for her to produce milk and the puppy will have to be nourished another way.

The opposite can also happen. If the mother produces more milk than the puppy needs, she may develop mastitis. This is extremely painful for her.

There is also a chance that the puppy may drink too much milk since it doesn’t have to compete with others. This can create a situation where it becomes too heavy to actually be able to learn to walk.

Lack of heat is also a danger for the puppy. In larger litters, the puppies cuddle together for body warmth. The singleton puppy can curl next to its mother but she will need to go outside and eat, which leaves the puppy alone and without heat unless other measures are taken.

A puppy also strengthens its muscles by climbing over its siblings and playing. Without those siblings, the human in charge needs to make sure the puppy gets enough exercise in order to grow strong.

During a puppy’s first eight weeks, it basically learns how to be a dog. This is done by interacting with its littermates. A singleton puppy will not learn the necessary things such as bite inhibition, how to deal with frustration, or knowing it can’t always get what it wants because they don’t have that competition.

He won’t know how to interact with other dogs or learn proper body behavior. This can be remedied by having another mother with a litter foster the puppy but this may create stress in the birth mother.

Alternatives include getting the puppy in a training class very early and learning ways to mimic the things littermates teach. In all cases, the human in charge will need to spend more time with a singleton than with puppies born with siblings.

Why would a dog only have one puppy?

There are several different reasons a dog might have only one puppy. Let’s take a look at the most common reasons

Death of Siblings

It is possible that the dam was going to have a larger litter but the rest of the puppies died before birth. In this case, the rest may be stillborn.

The Age Factor

If the female is over five, she is more likely to have smaller litters because her body has become tired. A male sire who is over seven may not have as many sperm as he once had. This means there are fewer to fertilize the eggs.

Timing

A female dog doesn’t release all her eggs at once. If she is bred at the very beginning of her cycle or at the very end, it is possible that there weren’t as many eggs to be fertilized. If she only has one breeding session, this can also make it less likely that more than one egg is fertilized. Dogs giving birth in the spring often have larger litters than those giving birth at other times of the year.

Breed

Some breeds naturally have smaller litters. The Scottish Terrier is notorious for producing singletons. Smaller breeds are also more likely to have singletons because their litters are naturally smaller anyway.

Genetics

This isn’t a huge factor but there has been evidence that females who are born as singletons are likely to have at least one solo birth. If a female has had a solo birth, her chances of having a second is also increased. The more inbreeding there is, the greater the chances of a singleton birth there is. 

Health and Nutrition

The relative health of both parents, but especially the mother, is a factor in how many eggs she produces and how many puppies she can carry to birth. If she doesn’t have proper nutrition, it will also make it more difficult to carry several puppies to birth. 

Author

I created and currently manage Pet Dog Owner, the website you can go to when you have questions about your dog's behavior. It is my hope that you find Pet Dog Owner to be a helpful resource. It is also my hope that it will help you to improve your relationship with your dog. You can read more about me and my website here.