Almost everyone who has had some sort of exposure to cats has seen a litter of kittens! Besides being adorable balls of fluff, one of the things that are most noticeable about many litters is that at least some of the kittens may look nothing like their mother or father (unless the cats have been carefully bred).
Cats that get out unexpectedly in particular are more likely to have litters where the kittens all look different and can even have a little split over a few days! So, what gives? Can cats be pregnant with two different litters? Or is something else going on?
Short answer: Cats can have two (or more!) litters, and they can have multiple litters a year and furthermore, each litter can have more than one father! When this happens, each kitten can have different genetics from others in their litter, leading to a different appearance and even temperament. It is perfectly normal.
Cats and Their Reproductive Cycle
There’s a good reason why there’s a massive push to get cats spayed as much as possible, as soon as possible. Cats are quite proliferating breeders, capable of having two to three litters of kittens a year and able to breed from about four to eight months of age all the way up to about age 8. This can give each cat upwards of 150 kittens over their reproductive span!
But cats are also able to have kittens with different males. This is what’s called “superfecundity” and it’s the idea that females can be impregnated by multiple males. All mammals have the capacity to have superfecundity, including humans, though it’s less common in most.
In cats, being pregnant does not stop them from going into heat, with 10% of cats going back into heat between weeks three and six of their pregnancy. Furthermore, a female cat will produce multiple eggs because egg production is induced by mating.
When she produces several eggs and if she mates multiple times, the eggs can be fertilized by multiple fathers. Fertilization in cats is fast, unlike humans or other mammals, so getting fertilized by multiple males is quite common.
Why did cats evolve this way? Simple. If a couple of kittens from the father end up being unviable, it won’t mess up the rest of the kittens, and the problematic DNA doesn’t get passed on or impact the rest.
It makes sense when you consider that most feral cats really only have a life expectancy of a few years, so they are going to want to breed as often as they can, with as many males as they can, to produce as many viable kittens as possible.
In the case of cats, if you’re picturing a cat with three mates having three times as many kittens as a cat with one, you can rest easy.
Once a cat’s eggs are fertilized, they go to the womb and begin to develop, regardless of when they were fertilized. This means that a cat can have two litters developing at the same time, each with different genetics.
They will follow a roughly similar timeline of development and be birthed at roughly the same time. (Although it’s not terribly uncommon for a cat to give birth to a few kittens one day and ‘finish’ a few days later! This is because some eggs may have been fertilized a few days later than the rest).
Each kitten will still only have (genetically), one father and one mother. All the littermates will share the same mother, but they may have different fathers. This is where the superfecundation comes in.
However, just because your kittens look different doesn’t mean that a superfecundation has happened. Kittens can look different from one another even if they all had the same father, due to the way that genetics impacts coat color, eye color, and overall build.
The only way to know for certain is if your kittens are wildly different (like some have long hair, and some have short or some of taken on wildly different features compared to the mother) or by doing DNA testing.
Really, DNA testing is the only way to know for absolute certainty because genetics can cause a litter of kittens to all look a little different, even if they do have the same father.
How Common Is This?
Superfecundation is very common in cats with estimates ranging from 70-83% of litters having more than one father! But the environment the cat lives in will have a huge impact on these numbers. City cats are far more likely to birth a litter with multiple fathers, whereas a country cat is a lot less likely to have that happen, simply because there are fewer tomcats.
You also have to take into consideration the lifestyle of a cat. A strictly indoor cat is less likely to have a litter of kittens sired by multiple fathers because the breeding is more likely to be supervised. A feral or stray cat on the other hand has access to more tomcats and thus, it’s far more likely that the litter will have multiple fathers.
But there really is nothing to worry about anyway (unless you are a breeder) because it doesn’t hurt the litter and has no impact on the birth (though you may get a couple of slightly premature kittens which is pretty harmless).
Superfecundation is a normal part of a cat’s reproductive cycle and serves the evolutionary purpose of making sure that the litter overall is as strong as possible.
Cats can absolutely have more than one litter of kittens (genetically) speaking. And superfecundation isn’t just found in cats; it’s been seen in dolphins, fish, hares, and badgers.
It’s even been seen in humans, though it’s extremely rare and usually tied to IVF treatment. With cats, it’s extremely common and an evolutionary advantage. It also means that it’s quite common to get littler of kittens that all look different!
Though they are still all adorable balls of fluff.
Have you ever seen a littler of kittens that all looked wildly different from each other and from their mother?
Pam is a self-confessed cat lover and has experience of working with cats and owning cats for as long as she can remember. This website is where she gets to share her knowledge and interact with other cat lovers.