In March, we asked our fellow furry friends on our Instagram: ‘What would you like to know about cats?’ We received a response which peaked our interest. The question asked 'how can cats be from the same litter but have different fathers and breeds?' It’s an interesting question and one we wanted to know the answer to. The simplest answer to this question? It’s superfecundation.
What Is Superfecundation?
According to Merriam-Webster, superfecundation is defined as ‘successive fertili[s]ation of two or more ova from the same ovulation especially by different sires.’ It’s a straightforward answer to a question that isn’t commonly asked. We knew that there had to be more to it, and we were eager to dive in and learn more.
How Does It Work?
It’s all about biology! The mating cycle of cats (aka being in ‘heat’) are determined by the seasons, typically ‘spring and summer’ when temperatures are higher and the days are longer.
Throughout a female cat’s reproductive life, they will go through periods where they constantly make noise and they won’t sit still. They’ll ‘roll around on the ground and rub up against objects.’ This is the first sign that a female cat has entered the mating cycle. While the chances of a female allowing a male to approach her at first is small, she’ll ‘allow a … [male] to approach her and mate’ further in the cycle. It’s very common for a female to mate with multiple males during a cycle because it increases the chances of fertilisation.
After the mating process, the female will release a number of eggs from her ovaries into the reproductive tract. If the female had mated with more than one male while she was in heat, the chances of different eggs being fertilised by sperm will increase.
The Results?
Multiple kittens that look different from each other! According to vet, Dr Donald Shellenberger, the most obvious way of seeing the results of superfecundation is if the kittens ‘look drastically different from each other.’ Similar to humans, cats have recessive genes so characteristics like coats and eye colours aren’t the best indicators of superfecundation. However, if the kittens look as if they are of different breeds then you’ll know what occurred.
While it’s unlikely for it to happen to a female house cat (especially if the cat is the only animal in the house or tends to stick to themselves), superfecundation is very common amongst strays. It’s one of the reasons for why desexing cats is so important. So there you have it. It is possible for a litter of cats to have different fathers.
Written by Matthew Leong for FFARQ