If you’re squeamish, look away now. Chinchillas reproduce by mating, like all mammals do. But how do they do it, and how does the chinchilla reproductive cycle work?
How do chinchillas mate? The male mounts the female from the rear. He produces sperm while she produces an egg/s. After mating, the male produces a copulatory plug to close the female’s vaginal opening. The female goes through ‘estrous’, meaning a period of being in heat between November and May which lasts 30-50 days.
Because females are bigger than males, they fight off unwanted suitors. This can hurt or even kill the male, so if you plan on mating chinchillas, you must monitor them.
How Do Chinchillas Reproduce?
Chinchillas are mammals. This means that they reproduce in a similar way to other mammals. A male and female will mate, which will result in an embryo. The male provides the sperm while the female provides the eggs. This embryo will then develop inside the female’s womb into a baby chinchilla (kit).
Once the kit is born, the pair will mate again and try to have another litter. All of this applies to pet chinchillas as it does to wild chinchillas.
Note: The guide below endeavors to be as scientifically accurate as possible. As such, there might be some terms that you’re uncomfortable with, but nothing that you wouldn’t hear in a biology class. But if you’re intent on breeding chinchillas, these are all things you need to know and become comfortable with.
Do Chinchillas Have Sexual Organs?
Chinchillas have sexual organs like those of other mammals. The male has a penis while the female has a vagina. Unlike other mammals, the male chinchilla’s testes are internal, as are the female’s ovaries. This makes sexing (telling which sex a chinchilla is) slightly more difficult.
The difference between male and female chinchillas is known as ‘sexual dimorphism’. In other ways, male and female chinchillas are the same: both males and females have nipples, for example. They are the same shape and color, behave almost the same, and don’t have other obvious features which can show the difference between males and females of other species. That being said, females are generally heavier and larger than males.
How Do Chinchillas Mate (Step by Step)
Mating begins when the female is in heat. If the female is not in heat, it will normally reject the male. Mating is performed as it is in most animals, with the male mounting the female from the rear. He will move his hips backwards and forwards, often starting slowly and getting quicker, while twitching his nose. The female will sit still at this time. When she heads off, he will sit on his hind legs and groom around his genital area to clean it and prevent hair rings.
The female may initially be reluctant to mate. This is natural behavior, because the female wants to only mate with the best possible males. You may notice the female:
- Standing on her hind legs
- Spraying urine, either generally or at the male
- Whining or making other loud noises
These are all behaviors which indicates that the female feels threatened: so, by standing up, she makes herself big to try and scare off the male. If this continues after a few minutes, you should separate the pair. That’s because the female is usually larger than the male, and could hurt him if he doesn’t leave her alone.
Mating doesn’t last a long time. Afterwards, male chinchillas create something called a ‘copulatory plug’. This is something that lots of rodent species do. The plug, as it’s called in short, is made of coagulated (somewhat solidified) semen. It is produced during mating and plugs up the female’s vaginal canal. It serves two purposes: first, it stops other chinchillas from mating with the female. This stops the male’s sperm from having to compete with those of other males, if the female mated again. It also disintegrates over time, which allows the release of extra sperm as it does so, again increasing reproductive success.
When Do Chinchillas Mate?
Chinchillas mate between November and May in the northern hemisphere. Mating can take place during this time when the female is in heat.
The act of mating typically takes place in the early evening or night, because this is when chinchillas are the most active. But some chinchillas adjust their schedules to better match those of their owners, so that they get more stimulation. These chinchillas may mate during the day instead, as they’re less active at night.
The Chinchilla Reproduction Cycle
The reproductive cycle determines when mating begins, and when mating is successful, in female animals. If you have studied biology, you will be familiar with the menstrual cycle; this is one form of the reproductive cycle. Other animals regulate mating in different ways, e.g. by going into and out of ‘heat’.
Chinchillas are one such animal which goes into heat. This means that chinchillas can only mate successfully (i.e. conceive) during these times. The times when mating would not be successful are termed ‘anestrous’. There are three kinds of estrous cycle:
- Polyestrous. The cycle comes and goes throughout the whole calendar year (e.g. one month of being in heat, followed by one month of not being in heat, followed by a month of being in heat).
- Seasonally polyestrous. The cycle comes and goes but only during part of the year: one month estrous, one month anestrous (and so on) but only during Summer. No mating or conceiving occurs in any other season.
- Monoestrous. There is only one period of being in heat in a calendar year, e.g. the early Spring. All other times are anestrous.
Chinchillas are seasonally polyestrous. Their mating season is between November and May in the northern hemisphere. In the southern hemisphere, mating instead takes place between May and November (the opposite). The majority of chinchillas stick to this ‘schedule’, while some which are especially fertile can reproduce throughout the year. The breeding season is long because gestation takes a long time too (110-120 days average). This means that kits conceived in November in the northern hemisphere will be born at the end of February, just when Spring is arriving.
The chinchilla has an estrous cycle of 38 days on average. Each heat lasts three to four days, with a three to four gap before the net one. These heats can continue for a total of fifty days. There are normally two in a row, before the female becomes sexually dormant again. This whole system is controlled by hormones, which trigger the individual stages of estrous and anestrous.
Egg Production in Chinchillas
Mammals produce offspring through the combination of sperm and eggs, which is achieved through intercourse. It’s the female which provides the eggs.
When the female is in estrous, eggs will become available through a process called ‘ovulation’. This is where the egg travels from the ovaries, where it originally developed, down the Fallopian tube. When reproduction occurs, it is here that the sperm and egg combine. The egg then travels further along the Fallopian tube to the uterus, where it can develop into an embryo (baby). The movement of the egg is triggered by time, not by reproduction. This is referred to as ‘spontaneous ovulation’, while ovulation being triggered by mating is called ‘induced ovulation’.
Many animals produce only make one egg available at a time, but chinchillas make 5-6 available during each estrous period. This is part of the reason why chinchillas often have two or more offspring in a litter.
Do Chinchillas Have Periods?
Chinchillas don’t menstruate. Menstruation is where the lining of the uterus (womb), together with an unfertilized egg, are flushed out of the body when no longer needed. As such, it stands to reason that chinchillas have to do this if they don’t successfully mate.
But rather than menstruating, chinchillas reabsorb the uterine lining while the eggs remain in the Fallopian tube for the next period of heat. This is beneficial to wild animals because the loss of lots of blood and tissue must be accounted for, e.g. by eating more food. This is almost like recycling instead.
This doesn’t negatively affect fertility, and the process can begin again a few days later. As such, you should not see lots of blood around your female chinchilla’s rear end. This is not menstruation, and is likely something which requires medical attention.
How Long is the Chinchilla Gestation Period?
The estrous cycle is paused while the chinchilla is pregnant (gestating). The chinchilla gestation period lasts roughly 110 days for short tailed chinchillas, and 120-130 days for long tails.
This is a reproductive strategy which is different to other rodents, which have short gestation periods of as little as three weeks. It allows the chinchilla kits to develop further than other rodent litters: they are born with fur, with their eyes open, and their ears open. They can defend themselves with their teeth from their earliest moments. Young which can do this are known as ‘precocial’.
The chinchilla reproductive cycle can begin again a day before birth. The female wants to mate again as soon as possible to create another litter and pass on its genes.
How Many Kits Do Chinchillas Have?
Chinchillas have smaller litters than other rodents do. It’s common for a chinchilla litter to be only one kit. 1-2 kit litters are the most common, with 3-4 possible but rarer. Litters up to seven or eight are also possible, but very infrequently seen.
How Many Litters Can Chinchillas Have in a Year?
Small wild animals must produce lots of offspring because they can easily be predated on by bigger animals. That’s why most rodents have many offspring per litter, and many litters per year.
While chinchillas don’t have lots of kits in one litter, they can have more than one litter in a year. A paper in the journal Theriogenology looked at the topic of chinchilla reproduction (although they did look specifically at farmed chinchillas, so the precise numbers may be different for pets and wild specimens). They found that females averaged between 1.2 and 2.4 litters per year.
This is less than other rodents, but there is a good reason why. The chinchilla gestation period lasts roughly 110 days for short tailed chinchillas, and 120-130 days for long tails. This means it’s physically impossible for a short tailed chinchilla to have more than three litters in a year. And accounting for periods of rest and recuperation, and imperfect breeding schedules, chinchillas can only average two litters in a year.
What Age Do Chinchillas Mate?
Chinchillas begin mating and producing offspring from 10 weeks old. This is inconvenient for the owner, because this may be before all of a mother’s litter are weaned (8-12 weeks). This can result in inbreeding.
Ideally, you want to breed chinchillas long after this initial onset of fertility. Some chinchillas continue growing until they reach 18 months, and the smaller the chinchilla, the less likely it is to successfully mate and deliver a litter. As such, breeders wait until the chinchilla is a year old before breeding it.
There is no rush in breeding chinchillas. If they’re cared for properly, they can live to between twenty and thirty years old. This means that the average chinchilla can have two dozen litters throughout its life even without mating at every possible opportunity.
Do Chinchillas Mate for Life?
Most sources state that chinchillas mate for life. It’s true that chinchillas can bond, and that a mating pair of chinchillas could live in a cage together for their whole lives. However, there are important caveats to be made, and it depends exactly what ‘mate for life’ means.
Chinchillas are largely monogamous. They will mate with the same partner throughout a mating cycle (estrous). However, neither females or males are averse to mating with other chinchillas during this time period, as these animals’ primary objective is to spread their genes and reproduce as much as possible with the best mates possible.
Moreover, chinchillas do not love each other as the term ‘mate for life’ can imply. While they can bond, to think that chinchillas can ‘love’ in the same way that people can is to anthropomorphize them. Experienced owners avoid doing this because animals are different to people, so to think of them in the same terms as you do people is to misunderstand them. Chinchillas can also find new mates after their partner dies, so it’s wrong to think they ‘mate for life’ in this sense too.
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How to Mate Chinchillas
Breeding chinchillas is lots of fun, if you know how to do it right. For a fully detailed guide on how to breed chinchillas, follow this link. Here’s a brief run-down of what you have to do:
- Pick your chinchillas carefully. Certain breeding combinations are lethal, and you want to breed chinchillas which have nice thick fur or a large size.
- Prepare a cage for the kits the pair will produce. You may need more than one, depending on how many kits the female has.
- Introduce the pair. Keep the male and female in separate cages, two inches apart. This lets them smell each other and get used to each other, but fighting is impossible.
- Encourage frequent playtime. Once the pair seem happy in each other’s company, you can house them together.
- Check for mating and pregnancy. Discarded mating plugs and small clumps of hair are signs of mating; get a vet to X-ray your pet for confirmation of pregnancy.
- Wait. Gestation takes 110+ days in chinchillas!
In all other ways, care for your pets according to approved guidelines. Diet is especially important for the mother, as availability of key nutrients affects kit size. Consider switching the female to alfalfa hay as this is higher in protein and fat.