Rats - Does or Bucks?

Rats - Does or Bucks?

If you are thinking about keeping rats as pets you will need to decide if you will have males ‘bucks’, or females ‘does’. Both sexes make for great pets, but there are some differences between the two.

In this article I will cover most of the differences between the two sexes, but keep in mind that these are typical examples. Every rat has its own personality; it’s not unheard of for some bucks to act more like a doe, and vice versa.

Characteristics of Bucks

Male rats are nearly always larger than females, often growing to as much as twice the size of a small female. Their fur will feel a little coarser and sometimes look a bit unkempt, they can also have a musky odour sometimes.

One of the downsides to male rats is that they mark their territory fairly often by leaving urine or droppings. This can tend to smell a bit if built up over time, but with a large cage, not too many males, and good housekeeping it should not be a problem. The amount and frequency of territory marking is dependent on the individual rat, some are much more active than others.

This usually comes as a surprise to new rat owners, but while bucks really like social interaction, they tend to be very clingy and lazy. If you place a male in your lap or by your side, it will likely sit there for an hour or so just relaxing.

If a buck becomes hostile and aggressive to his other cage mates it is likely due to high hormonal levels, you may need to have the rat castrated to put a stop to this behaviour.

Characteristics of Does

Does are smaller than bucks and have much smoother well kept fur. They do feel softer to stroke and are often chosen as pets for younger children mainly for this reason.

Females are a lot more active than bucks. They are also more agile and will often make quicker movements or climb in ways that male’s cannot.

While bucks really enjoy the social interaction with humans, does are not so interested. They are much more independent and active, if you take one out of their cage to sit with you it’s unlikely they will sit still for long.

Unfortunately female rats are more likely to develop mammary tumours, the percentage chance of a female developing a mammary tumour is reported to be as high as 50%. The most common places to spot a tumour starting are in the armpit, on the belly, or the chest. You will need to seek veterinary advice if you think your rat has a tumour, this will often result in a costly removal procedure.

Does are on heat every 5 days for around 12 hours, this is why you should only cage one sex together. Unless of course you want to breed your rats, but breeding rats should only be done if you are well prepared.

How to tell the sex of a rat

This is really easy to do with rats, female rats have nipples and males do not. Just carefully pick up a rat and take a look on their underside, it will be obvious if there are nipples and leaves almost no chance of making a mistake. If you are still not sure, or want further proof, males have large testicles that are hard to miss too. It does not take long for male rats to develop, at 6 weeks old you will certainly be able to tell if a rat is male or female.

Aggression and biting

It is often assumed that male rats will be aggressive towards humans. This is not the case at all, you may get the occasional nip at your fingers but they are not aggressive. There can be instances of aggression between male rats however, this is often due to territory conflicts or elevated hormonal levels.

There will usually be warning signs of a male rat becoming aggressive. They puff out their fur to make themselves look bigger, make hissing noises and act more erratic. If you can see this happening then exercise some caution and do not handle the rat.

Female rats are a bit more unpredictable, although it is very unlikely you will get bitten with no warning. Again, if a rat is showing signs of being in an erratic state there is an increased chance of being bitten. Female rats are more likely to bite when they are pregnant or have recently given birth, this is because they are being protective of their young.

So, what is best for you, Bucks or Does?

Male rats usually suit the kind of person who likes spending time with their pets and form closer bonds. It’s common for owners of male rats to sit stroking their pet watching TV together in the evenings. So if you have a lot of time to dedicate to your rat you can gain a lot more from males.

Female rats are more suited to people who want to watch their pets and enjoy seeing them being active. You can add more accessories into the cage like a running wheel, obstacles and hanging platforms. Does will happily jump around and are always curious to check out new toys.

After reading all of the above information, if you are not bothered whether you want males or females that’s fine. If you are buying off a breeder or a private owner you can ask them what kind of habits and temperament the rat has before buying it.

Both males and females should be given the same amount of cage space, and require roughly the same amount of food and water. Rats are not a low maintenance pet, ideally they require some type of stimulation daily. Although males do need a little more attention, females need some out of cage time daily too.

This is probably one of the most important factors to consider before choosing rats, you need to be able to spare between 30-60 minutes a day to let them out of their cage or interact with them.



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