Rabbits are animals that can use scent to communicate. However, they are not smelly pets to own. Rabits are animals who spend a considerable amount of time keeping their fur clean.
In general, their bodies and fur do not stink. Yet, they can sometimes produce smells that are offensive to human noses. One smell in particular that rabbits make that can be off-putting to people is when they smell like a fresh cut onion.
There are a few reasons that a rabbit might produce this smell, but it is not typically an alarm that something is wrong with your furry friend.
Is it normal for rabbits to be smelly?

Smells that rabbits produce
A common question that people ask about keeping an indoor rabbit is, “do they smell?” As long as their living area is cleaned frequently, the answer is no.
Generally, rabbits are not pets whose bodies smell bad enough that they would need any sort of bathing or cleaning. However, on-demand, they can produce a specific smell that can actually help them in a variety of ways.
The smell they produce is a musk from their scent glands. Some describe it as smelling like a fresh-cut onion.
To humans, this can be a strong and offensive stink. To rabbits, this smell can send strong messages to other rabbits.
The strength of the smell can also differ from rabbit to rabbit as their health can help determine the strength of the smell.
Another factor in the strength of the smell is whether or not they have been spayed or neutered. Rabbits who have been altered do not scent as often or as potently as rabbits who have not been altered.
Frequently, it is the unaltered male rabbits who are more likely to use their scent-making ability.
How do rabbits produce an onion smell?
Located at the rear of a rabbit are a pair of glands that, once the animal has reached sexual maturity, will produce a dark, thick, somewhat sticky, tarry substance that some people would describe as smelling like an onion.
Others say it smells more like skunk, or human body odor. Another name for this substance is musk.
Rabbits as young as five months of age have the ability to produce this scented material. It is also worth noting that once a rabbit begins to produce this smell, it is a good indication that the rabbit is old enough to be spayed or neutered.
Why would my rabbit smell like onions?

Enticing a mate
One major reason that a rabbit would emit a strong onion-like odor is to attract a mate.
To humans, the smell can be unpleasant. To other rabbits, the musky odor sends important information.
The smell can let a potential partner that they are sexually mature and are available to mate. They radiate this perfume as a way to let other rabbits know about their health, feelings, and desire to mate.
Territory marking
Along with the glands on the rabbit’s bottom, there are also some scent glands under the rabbit’s chin.
A rabbit will go around their area and rub the underside of their face on things they consider their property.
Effectively, the rabbit has left their scent on the item to let other animals know that this is their property.
They will pay special attention to mark their scent on things when they are in a new environment. It is a way for a rabbit to let others know that this is their area.
Introducing rabbits to one another
When a rabbit meets another animal, it cautiously takes in the scents of the other animal as a way to collect information.
It is assessing the situation to see if the other animal poses a threat. It is also checking the other animal’s emotional state and health status.
The rabbit may give off an onion smell to invite or rebuff the other animal.
Rabbit’s health
A rabbit’s odor can be affected by the foods they eat. Some strong-smelling herbs such as cilantro and basil may play a part in making a rabbit produce urine that smells like onion.
It is best to speak with a veterinarian to determine what supplemental foods to eliminate from their diet.
Do I need to clean my rabbit’s scent glands?
How to locate a rabbit’s scent glands
In order to decide whether or not your rabbit needs help cleaning its scent glands, you need to visually inspect them. Depending on how wiggly your rabbit can get, you may need help from another person.
First, collect your rabbit and make sure you are holding it in a way that it feels secure. Either you or the other person needs to get the rabbit into a seated position while keeping a hand under the rabbit’s arms.
While the rabbit is in this position, look in the area that is between its legs, but just in front of the tail.
This is the rabbit’s anus. Once you have found that, carefully use two fingers to gently spread the area around the anus.
Once you have done that, you will see something that looks like a slit on either side of the anus. These are the rabbit’s scent glands.
How often do I need to clean my rabbit’s scent glands?

When there is a constant musky odor
If you are constantly noticing that your rabbit is emitting a strong onion-like smell, it is worth checking to see if your rabbit needs help cleaning its scent glands.
Most of the time this is something the rabbit can do on its own.
However, if the rabbit is overweight, older, or has a disability that prevents it from reaching its own behind to clean effectively, it may need some intervention.
Visibly clogged ducts
When you locate your rabbit’s scent glands and see that the gland is filled with the sticky substance, it may be a good time to help the rabbit clean the glands.
Usually, a rabbit will not let their glands get to the point where the musk forms a large ball, but if it does, it is a good idea to take the time to clear them out.
How to clean my rabbit if it stinks like an onion?
Gather your supplies
You will need cotton swabs, cotton rounds, a tissue or paper towel, and warm water in a disposable cup. You may need gloves if you are not comfortable handling your rabbit’s musk on your own.
Gather help if you need
If you need it, make sure you have an assistant. You might need someone to either hold the rabbit or to do the actual cleaning.
It is better to have someone help at least the first time so that you can get a feel for the procedure so that your rabbit can stay comfortable throughout the entire process.
Position the rabbit
Get the rabbit into a seated position so you can see their rear. Locate the scent glands using the method given above in “how to locate your rabbit’s scent glands.”
Use a cotton swab
Once you have exposed the glands, dip a cotton swab into the warm water and gently dig at the underside of the ball of musk.
The warm water will help soften it so that it is easier to remove. Once you have the musk on the cotton swab, either place it on the tissue/ paper towel to dispose of when you are done with everything.
Once you have finished cleaning the first gland, move to the other side and repeat the steps to remove the musk.
Wipe down
When the glands have been cleaned, use the warm water in the disposable cup to wet a cotton round.
Once you have done that, gently wipe the area around the rabbit’s anus to make sure that none of the musk has been left behind.
Gently release the rabbit back into its home area and discard the supplies used in the cleaning.
Cleaning a rabbit’s body
If the rabbit’s body or fur smells like onion in one spot, take a clean cotton round and dampen it in warm water.
It is up to you if you want to wear gloves to protect yourself from transferring the smell onto your own skin.
Take the cotton round and gently rub it on the area that smells like onion. Be careful to not be overly aggressive as not to irritate the sensitive skin.
If the rabbit has a persistent all-over smell of onion, it may be necessary to take the rabbit for a visit to the vet.
There are many different reasons that your rabbit may have a strong smell, and there are different things that can be done to remedy the situation.
In all, having a rabbit that smells like an onion is not a permanent or bad thing. It is their way of silently communicating, which is an advantage for small, prey animals.
Releasing odors can let them safely communicate in uncertain situations, or can send signals of romantic interest.