African Soft Fur Rats (ASF), scientifically known as Praomys natalensis, are gaining popularity among pet lovers and reptile keepers alike due to their exceptional qualities. These medium-sized rodents, originating from Africa, are known for their distinctively soft fur, inquisitive nature, and high reproductive rates. Understanding their specific needs and unique characteristics is essential to ensure they thrive, whether as feeder animals or beloved pets. Multimammates are also referred to as African Soft Furred mouse.
Often favored by reptile enthusiasts, these rats serve as an excellent source of live prey for medium-sized snakes. ASF rats are known for their distinctively soft fur, inquisitive nature, and high reproductive rates. They can produce large litters, sometimes exceeding 20 young, which makes them incredibly efficient breeders.
In more recent years, they've been more commonly seen throughout the pet trade. As a nocturnal species of mouse, they’d commonly go foraging for food at night. Multimammates also eat an omnivorous diet consisting of both animal and plant materials - even extending to cannibalism under extreme pressure for food.
Distribution map of Praomys natalensis
General Information
They're typically used as reptile feeders as they're prolific breeders; they’re referred to as Multimammate mice/rats due to their multiple mammary glands; they generally have 8-12 pairs of mammary glands, but there have been documented numbers as high as 18 pairs! That is a drastic difference compared to female house mice which only have 5 pairs. They have a reputation for having large litters.
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They are thought to be the evolutionary link between the true mice and the true rat having characteristics of both. They are found in most parts of Africa other than the mountains and the desert and are one of the many animals preyed on by wild ball pythons. ASF's come in a variety of patterns and colors, some of them being: Self Agouti (common wild type), Pied Medium Agouti, Pied Dark Agouti, Pied Pink Eyed Dilute Agouti (usually referred to as "albino").
Physical Characteristics
Generally larger than traditional mice, ASF rats have a head and body length of about 15 cm with tails reaching around 11 cm. They typically weigh a maximum of between 60 to 130 grams, with males being the larger of the two sexes. Also as their name suggests they have soft fur. They are a little bigger than a mouse and have very very large eyes. Their soft fur is not just a delightful trait but also serves as insulation in various climates.
Lifespan
The average lifespan of African Soft Fur Natal Rats is around 2 to 3 years, similar to other rodents like mice and rats.
Housing and Enrichment
Providing an appropriate environment for ASF rats is crucial for their well-being. ASF rats have to be housed in chew proof enclosures as they are very destructive. They also have to have 1/4" bar spacing. Tubs in a rack or glass tanks are appropriate housing. Care must be given that any mesh lid is made from chew proof material (metal) and no bigger than 1/4" spacing. Lid clamps should be used on glass tanks to avoid escape.
A spacious cage or aquarium is recommended, ideally one that is chew-proof. I feel ideally a properly made bin cage is the best cage for ASF. I prefer the 106/110qt bins or the huge Christmas Tree plastic storage bins! You can buy the 110 sterilite bin at target, and the 106 sterilite bin at walmart. They need windows cut out and hardware cloth added (attached from the inside). At the very least 20 gallons but more is better. Still, tanks are not the ideal cage.
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ASF rats thrive in temperatures ranging from 68°F to 75°F (20°C to 24°C). While they can adapt to room temperatures, it's essential to keep them away from drafts and extreme weather conditions. Lighting requirements are straightforward; a regular light cycle mimicking natural daylight hours is adequate.
They need windows cut out and hardware cloth added (attached from the inside). There are a lot of really adorable toys and accessories for sale as you can use fun hamster things as well. I think because of their less domesticated nature they can be more high energy. They definitely need lots of fun mental stimulation in their cages with lots to chew and I do suggest providing a wheel 8-12 inches with a solid floor-no mesh style or bar type wheels. But note some may chew the wheels.
Hides and wheels are not necessary but often will keep the ASF's content and busy enough that they do not try to chew the enclosure. This is particularily important when housing them in plastic tubs in a rack situation. 2x4's cut into 4 inch pieces, empty toilet or paper towel tubes, etc. make excellent and cost effective chew "toys".
Due to this strong social structure it is often impossible to add in new adults to a stable breeding colony.
How I set up my ASF weaners (multis)
Bedding
Emphasizing cleanliness and safety, the enclosure should be equipped with solid bedding and nesting materials. Aspen, pine pellets, etc. make good ASF bedding. Avoid cedar due to it's toxicity for rodents. Bedding should be deep as these rodents like to burrow in it and create nesting areas. Shredded paper for nest building should be added when using pine pellets for bedding.
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Suitable Bedding:
- Wood Shavings: Pine, aspen, and poplar are good options. You may have to shop around with different brands to see which ones are least dusty. I personally use poplar bedding, but it's pretty hard to come by.
- Paper Bedding: Carefresh, Kaytee, Frisco, and Oxbow are good options. Be sure to avoid dyed and scented options, as well as ones that include baking soda. They cannot consume baking soda, so it can be a risk when they chew on the bedding.
- Paper Pellets: Equine pine pellets, Vitakraft Fresh World Pellets (non-scented version), Yesterday's News (non-scented version), and Sunseed Bedding (non-scented/baking soda free)
Not Suitable Bedding:
- Cedar Wood Shavings
- Scented or dyed paper/bedding
- Includes baking soda (harmful for them to ingest)
- Clay based bedding
- Dust baths
Nesting Materials:
- Newspaper (not the glossy/waxy kind)
- Crinkle paper (typically used as gift filling)
- Packing paper
- Scrap fabric
- Cardboard
- PomPoms (not the shiny /tinsel ones)
- Timothy/Oat Hay
- **Avoid stringy material like stuffing or fluff.
Enrichment Items
ASFs are super active and love to explore! They benefit from multiple enriching items. I will list some of the ones I use and recommend as well as ones that may cause harm. This is not a complete list, so if you find items not listed here, feel free to send me a link or picture to ask if it is safe or not.
Suitable Enrichment Items:
- Exercise Wheels/Saucers: I prefer to use wheels and recommend the Kaytee Comfort Wheel 8.5" (solid plastic), Kaytee Silent Spinner 6.5", and the Ware Saucer (Medium).
- Wooden Chews: Most wooden chews for small animals and birds are suitable. If you're not sure about one, send me a picture!
- Hammocks: These can be as simple as cutting fleece into small squares/rectangles, making/sewing your own, or I do also have an Etsy shop where I offer all kinds of hammocks and beds!
- Houses/Hides: I like to have a few "indestructible" hides (usually plastic or ceramic) as well as some ones they can destroy (cardboard boxes, drink carriers, popsicle stick houses - fun to make!).
Not Suitable Enrichment Items:
- Exercise Balls: these are harmful for all animals. Their limbs can easily get caught in the slits as they walk/run in them, they provide little air flow/ventilation, and most rodents have poor eyesight, relying more on touch an smell. Being in a ball severely limits these senses, causing them to panic and continuously run to try to find a way out. This causes unnecessary stress and a likely chance of physical harm.
- Wire Wheels: there is a misconception that these cause bumblefoot, which isn't the case. However, I have personally experienced mice getting their toes/limbs caught in the grids, causing harm. I have also experienced mice breaking their spines when multiple are trying to run and get caught between the bars holding the wheel in place. So, I highly discourage using metal/mesh wheels.
- Items with small holes: Some houses/hides, wheels, etc. have small holes big enough for a mouse/ASF to fit their head it, which they will attempt. However, it isn't big enough for their whole body to fit. This can cause them to get stuck and harm themselves. Just be mindful of the items you are purchasing.
- Chew toys/treats held together by honey or molasses.
Diet and Nutrition
A balanced diet for ASF rats includes a mixture of commercial rat pellets and small animal seed mixes. A Multimammates diet isn’t the same as a domesticated house mouse, but it is similar. As they’re not commonly kept as pets, commercial pet foods are mostly unsuitable. People recommend making your own homemade Shunamite-style mix or feeding a good rodent-mix, fruits, vegetables, and the occasional live insects.
Feeding ASF rats should occur daily to ensure they receive adequate nutrition. Observing their eating habits will help you adjust portion sizes and diet frequency. Obviously, they need a water bottle at all times with fresh clean water.
Mazuri 6F or other quality rat lab block is recommended as their primary food (a wire mesh food hopper often works best for this). They will also eat a variety of fresh vegetables, in moderation, as well as wild bird seed mix and cat kibble. It is very common to observe nursing females eating feces.
Studies have shown stomach contents of Multimammates across Tanzania and Swaziland contained mostly seeds, grains, plant materials, invertebrates, fruits, vegetables, and unidentified matter. Contents were the same across both landscapes.
ASFs do best with a balanced block for their main diet. Below I will list some of the suitable options for them. This is not a complete list, but some of the more commonly found blocks. If you find other foods that you aren't sure about or feel would work, please send me a link so I can check over the nutritional values! I offer 1-2 8oz. water bottles per cage depending on the size of the enclosure.
Suitable:
- Mazuri Rat and Mouse Food (found in most pet store and online)
- Kalmbach 18%
- Sunseed Vita Prima
- Science Selective
Not Suitable:
- Mixes that include seeds and fillers (Kaytee, Vitakraft, Tropical Carnival, etc. These are not nutritionally balanced)
Treats
Giving occasional treats can help encourage trust as well as foraging if they are scattered around. I will list some good options for this!
- Old Fashioned Oats: I like to toss them around the cages in the bedding so they can dig and forage for them.
- Gerber Puffs: these are great low sugar options, and they can be bought fairly cheap for a container that'll last forever with these little guys!
- Yogis: These are higher in sugar, so I recommend giving them sparingly.
- Unsalted seeds and nuts: These should be given sparingly as well due to them being higher in fat
- Some fresh items to give are dandelion flowers and leaves (if picking them ensure they've not been treated by any chemicals), kale, apples, carrots, peas, eggs, and mealworms (dried or live).
Socialization and Handling
Multimammates need socialisation with their own kind, even when cohabiting with fancy mice. Roughly 3 multimammates per colony is the 'magic number'.
While ASF rats are naturally shy, daily handling can help build trust and confidence. Begin by gently introducing your hand to them, allowing them to sniff and explore. It’s crucial to approach them calmly to reduce stress, as sudden movements may frighten them. ASF rats are highly social creatures and ideally should be kept in groups to promote their wellbeing. They thrive in social environments, and establishing a hierarchy within the group allows for peaceful coexistence. ASF like most rodents are highly social and must be kept in good sized groups of three or more.
ASFs are social critters, but they do bond closely. They can be introduced to a male mouse or other ASFs while they're young, but once they reach maturity, they become aggressive toward any new cage mates. This makes it very difficult to add anyone new, so ensure you are getting the amount you'd like to have the first time around. Male ASFs can be housed in a pair or trio if they are raised together but cannot be introduced to each other later in life. Female ASFs do best in groups of three or more. They can also be introduced to a male fancy mouse to provide companionship without the risk of breeding.
Female multimammates cannot breed with fancy mice but can still provide socialisation. It is important to consider castrating your male mice before considering cohabbing with another species of mouse. Multis cannot provide the same level of interaction as that of their own kind.
They have an impressive jumping ability both in height and length and can move very quickly.
ASFs do tend to be a bit less handleable, but I do get quite a few that do pretty well! I don't have as much time to offer one on one handling/taming, so in a home with more time, I feel they could do well being picked up! ASFs haven't been worked with as long as mice and rats, so they are not as domesticated as those species. I work toward breeding those with natural sweeter/more tame temperaments in hopes of continuing that trend though.
When handling these guys, I recommend scooping them up over a secured area. That way, if they do end up jumping or hopping off, they're not able to escape or get far. It may help to use a bonding pouch to handle them as well so they feel more secure and are less likely to jump. These little guys are so curious and love to explore! I always enjoy watching them run around their enclosures, checking everything out, especially after a fresh cage cleaning.
Lift them by the base of tail either using your fingers or padded feeding tongs. Be careful not to damage their fragile tails. Note of caution: Even young ASF's can flip around, climb their own tails and inflict a strong nip. You can sometimes get a good hold on them by grasping the loose skin in between their shoulders but the tail grab tends to be the easiest. Do not transport them freely in your hands as they can very suddenly jump and will fall to the floor. A small kritter keeper is handy to transport ASF's in.
Will bite in defense of their young or a perceived threat to the colony.
Breeding
Breeding ASF rats is relatively straightforward due to their high fertility rates. Female ASF rats can become sexually mature as early as 2 to 3 months of age, with gestation periods averaging around 21 days. Responsible breeding practices should always be followed to ensure the health and welfare of both the parents and the young.
They are extremely easy to raise, have little to no natural odor and are very rarely refused as a prey item for snakes, especially "picky" eaters.
Establish your breeding group at the weanling stage so the rats can become accustomed to each other as they mature. This will tend to lessen any fighting. Breeding groups can be as small as 1.1 or as large as 1.6 or more, depending on the enclosure size. Most breeders tend to use a 1.3 or a 1.4 ratio. Gestation is approximately 21 to 26 days with an average litter size of 10 or more. The male will re-breed the female very shortly after she delivers a litter. This does not seem to affect the health of the breeding female and in fact, most females grow substantially after birthing their first few litters.
All females in the colony will nurse all of the young regardless of litter age. It is quite common to see young of various mothers and developmental stages all nesting together and being fed communally. Older offspring and the male of the colony are often seen assisting in the care of the youngest colony members. Breeding groups stay together their entire productive breeding life. ASF young should be weaned by one month of age. They can be weaned younger however, as long as their eyes are fully open and they are eating and drinking independently. When first weaned they tend to eat more of the small bird seed than the larger and harder lab block.
It is rare for a stable breeding colony to accept a new adult member without serious fighting which can lead to the death of the newcomer. Removing a breeding male, even for just a day, then reintroducing him to the colony can cause this level of fighting.
| Feature | Details |
|---|---|
| Scientific Name | Praomys natalensis |
| Origin | Africa |
| Size | Head and body length: ~15 cm, Tail: ~11 cm |
| Weight | 60-130 grams |
| Lifespan | 2-3 years |
| Litter Size | 10+ |
| Gestation | 21-26 days |
Hygiene
Although ASF's have very little natural odor you still need to clean their enclosures regularly. Usually every couple of weeks is fine but depends on the number of rats and the size of the enclosure.
Additional Considerations
If left without food or water for any length of time they can turn on each other. They do not require any additives to their water. If they have direct access to their water bottle it should either be glass or have a metal chew guard on it.
As with any live prey animal, monitor the feeding until the snake has full control and constriction of it's ASF. Alternately they can be fed pre-killed or frozen/thawed. Co2 is commonly accepted as the most humane and safe manner of euthanizing rats for later use as food for snakes.
ASF's have been found by many snakekeepers to be very useful in getting picky eaters or fasting snakes to start eating again. Some snakes will feed on ASF's as well as other rodents, some will take only ASF's.
Are you unable to let your rats out to play?
I do not feel this is a good pet for young children.
