Why cats don’t go in heat during winter?

As we already talked in the previous articles about cat heat cycles, most cats go in heat during the mating season from early spring till early autumn. In this article, we will explain why cats don’t go in heat during winter and how natural lighting can have its impact on the heat cycle of a female cat.

Cat in heat in winter
Cats usually don’t go in heat during winter. Photo © tuna – Fotolia.com

Unlike humans, who cycle monthly, or dogs who usually cycle twice a year, cats have a specific pattern of how heat cycle is organized. Most notable of this is seasonal breeding, that is, cats do not mate during winter.

Cats are not the only seasonal breeders. Horses, lemurs, groundhogs hamsters are few examples of animals, who, similarly like cats, become responsive to breeding when amount of daylight exceeds a specific threshold. Cats need 12 hours of daylight to initiate heat cycle.

Above mentioned animals are known as long day breeders, which simply states they breed only when there is a long day. Additionally, no surprise, there are short day breeders, as well. Few of those are sheep, goat, fox, deer and moose.

Why amount of daylight affects breeding of cats?

Okay, amount of daylight influences when cats, and other animals can breed. But why?

Main purpose, form natural point of view, for this is to ensure kittens are not born during winter. This is a period when the main food sources of cats, like mice and rabbits are hibernating, therefore, cats, who strive for their own survival, would not be able to care for their young properly.

Therefore, nature has provided a great workaround – cats do not go in heat during winter, ensuring, the first kittens will appear only at the middle of the spring. By then, it happens to be

This is controlled, believe it or not, by daylight. Studies show cats need at least 12 hours of continuous daylight to start cycling, which, in the most part of the world happens for a period of six to months during the warm season.

How daylight can affect heat cycle of cats?

So, the obvious next question is, how does this work? How can such a vague thing, as light be responsible for breeding of cats. The truth is, far more things than you can think of are influenced by the natural light coming from the sun. Most notable would be plants creating oxygen in a process known as photosynthesis. But so are heat cycles of cats dependent on natural light.

Have you heard a hormone names Melatonin? Carrying it’s name derived from Greek Melos – black, dark, it is also known as sleep hormone. It is released by most animals in the absence of light and helps to maintain sleep – wake cycle. This is why you feel sleepy during rainy days and why it’s hard to get back to sleep if you turned on light during the night.

But additionally main functions of melatonin, there are several more, including, melatonin suppresses Luteinizing Hormone (LH) and Follicle-stimulating hormone (FSH), both of which are very important in developing and maintaining heat cycle in most mammal females. If you don’t understand what we are talking about, read our article about hormonal activity of a cat during the heat, which is part of our series about cats going in heat.

Thing to note, however, is that not all cats stop cycling during winter. Short haired cats are known to cycle throughout the whole year, and also, artificial lighting can easily interfere with natural hormonal regulations of a female cat, as well.

But for most cats, in winter, when there is plenty of melatonin, cats would not breed, and would not create off-springs. Contrary, during spring and summer, when days become longer and melatonin levels decrease, cats resume to regular cycling frequency, and cat give a birth at times when their prey is abundant.