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Fancy Rat Breeders

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Fancy Rat
(Rattus norvegicus)

Article by Black Wolf Rattery

Introduction

Rats are amazing animals and make excellent pets. They are friendly and extremely intelligent. Like dogs, rats can be taught tricks, with proper training. Unfortunately, there are many misconceptions about rats. They are often described as dirty, vicious beasts who spread disease. Quite the opposite, rats are very clean. Many rats will actually choose one corner in their cage to use as a toilet. Many rats can also be litter trained. In fact, I have one cage of girl rats who have a litter box, and they use only this litter box as their toilet. Rats are highly unlikely to spread diseases to humans. In fact, the Bubonic Plague was blamed on rats for a long time, but has been proven to have been spread by fleas on the rat, not the rats themselves. Many people think rats carry rabies too. Like cats and dogs, however, the rat must first be exposed to a rabid animal to have rabies. Rabies is usually spread through saliva, so the rat must be bit or licked on an open wound by the rabid animal. If the rat is bit, they are unlikely to survive. Considering most pet rats are kept indoors, it is extremely unlikely one will ever come into contact with rabies. There is a much greater chance for a pet dog or cat to carry and spread rabies than for a rat. Rats are easy to care for too, similar to a cat or dog. A well bred, well cared for rat is also quite hardy.

Fancy rats, more commonly known as pet rats, are not wild rats. Pet rats are descended from wild rats, but there are quite a few differences. First of all, pet rats are often larger and longer lived than wild rats. They also come in a huge variety of colors, and even body types. Wild rats are not friendly to people and have a stronger "flight or fight" instinct. Domestic rats are very friendly to people, and even the unfriendly domestic rats can be tamed. Domestic rats are also less likely to bite people, and do in fact rarely bite, and only with reason. In ten 10+ years I have kept rats, I have been bitten three times, once by a protective mother, and twice by sleeping rats I mistakenly disturbed. There are also several species of wild rats, while almost all domestic rats are descended from one species: Rattus norvegicus.

Supplies & Housing

Wire cages are by far superior to aquariums when housing rats. Wire cages not only provide better ventilation, but are often larger for less money, and it is easier to make an enjoyable rat home. In wire cages, it is possible to hang branches, toys, hammocks, and more from the top and sides, which then provide the rats more stimuli and exercise. Aquariums can be used, however. It must be a minimum of 20 gallons for two rats only, but 30 or more is much better. It also needs to have a wire top so that there is at least some ventilation. Aquariums should also be cleaned out much more often than wire cages to prevent ammonia smell from urine from building up to unbearable levels. The wire top must be fastened down some how, or else the rats inside will quickly learn they can simply lift it up and jump out for a bit of an adventure. Bedding is a very important issue when keeping rats. They cannot be kept in a bare cage, however bedding selection should be done carefully. Two of the most common bedding available in most stores is cedar and pine shavings. Both of these, however, are extremely toxic to small animals. The natural oils in these woods cause respiratory problems. In addition, they have been shown to cause liver disease. Aspen, however, is safe to use. Paper-based bedding is also safe, and often better. Both aspen and paper-based bedding absorbs moisture and odor, and is comfortable. Dust content is different, and some people will say one absorbs better than the other. This narrows it down to preference. CareFresh is a popular brand of paper-based bedding, as is Yesterday News. Most rats enjoy making nests too, so some extra bedding material should be available for this. Some old towels or cloths can be provided for this use, as long as they have been washed first. These can also be removed to be washed. Be warned, rats will chew them up, so nothing fancy or irreplaceable should be given to rats. Very few rats like the fuzzy bedding made for hamsters. Some rats enjoy sleeping off the ground. For this reason, hammocks can be provided in wire cages. Ferret hammocks work just as well as home made hammocks. Old pants legs or shirt sleeves are excellent. Old cloths or blankets can also be used. The material should not be too stretchy, or the rats may not feel safe, and will therefore abandon it. Empty tissue or soda boxes can be used as homes. Plastic igloos for small animals are also available. Large reptile caves also make excellent homes. Rats are extremely playful, so toys are a must. A large variety of toys are available for small animals. Many ferret toys are suitable for rats, as well as some cat toys. Bird toys can also be used. When choosing toys that are not designed specifically for rats, check them over very closely. There should not be any holes where a rat foot or head can easily be caught, nor should there be loose ends that can fall out and be chewed on or swallowed by rats that may be potentially harmful. Rats do chew, so the toys should be durable and safe. Rolling balls (made for ferrets and cats) are often enjoyed by young rats. Empty toilet paper and paper towel rolls also make great toys. Exercise wheels can be used, but some rats do not enjoy these, while others absolutely love them. In wire cages, wooden bird perches and ladders can make excellent additions. Along with regular toys, rats also need chew toys. The most popular are wooden blocks available in most pet stores. Something of this type is necessary, since a rat's teeth grow continuously throughout its life. If the rat does not have something to gnaw on, there is a risk that it may not be able to wear down its teeth from normal use, and the teeth may become over grown. Some rats will never need chew toys, but it is always better to be safe than sorry.

As with any pet, a rat does need food and water bowls. The food bowls should be sturdy and well made. They should be heavy enough for the rat to sit on the edge without tipping it over, and should be made of a durable material that cannot easily be chewed. Heavy plastic and ceramic bowls are available. Other feeders are made of metal and can be hung in the cage. Any of these can be used. Water is best if kept in a bottle. Bowls are too easily soiled, if not spilled. All animals need clean water, with shavings, a bowl is just not suitable enough. Water bottles for rats should be a minimum of 8 ounces, but the larger the better, especially in areas where hot weather is common. Some rats do enjoy swimming on warm days, so a shallow bowl with some water (no more than one inch) can be provided in addition to a bottle. The bottle should be hung so the nozzle is one to three inches off the ground, depending on the age and size of the rat.

A carrier is another important supply to have on hand. Like other animals, rats should have regular veterinary check ups. When traveling, a rat should never be loose. A carrier can be anything from a simple box, to an expensive plastic carrier. My personal favorite are airline carriers.

Food

Rats are omnivores, so should have a bit of both plant and animal in its diet. To remain healthy, a rat must have a varied, well balanced diet, much like people. In fact, a rats diet is very similar to a person's. Rats can eat just about anything, keeping in mind the healthy guidelines for people match those of rats; that is, no foods high in sugar, fats, or salt. Candy and junk food should avoided by rats, just as it should be avoided by people.

The main staple of a rat's diet can be commercial food. Some commercial foods are not the best, however. The most common kinds are grain mixes. Another popular commercial food is a formulated pellet, often called lab blocks. Any food mix, however, should have little to no alfalfa pellets, rats general do not eat these. Small amounts of a high quality dog food can be fed too. This should not be the main part of a rat's diet, however, as it can be too high in protein for some rats. These commercial diets must be supplemented with other foods, if for no other reason that to add some variety.

Fruits and vegetables are excellent foods for rats. These should be clean and seeded. Some fruits and vegetables will also need to be peeled. In particular, citrus fruits should be avoided. The fruit should also be cut into pieces so the rat has an easier time handling it, and so there is at least one piece for every rat in the cage, preferably with some extra. Most vegetables can also be given safely. Some should be avoided, however, such as lettuce and cabbage, onions, or peppers. Large vegetables should also be cut up. After the rat is done eating, uneaten portions of fresh foods should be removed to prevent bacterial and fungal growth.

Almost all rats love bread. White breads should be avoided. Whole grain bread makes a great addition to any diet though. As an occasional treat, raisin bread can also be given. Hardened bread also provides something for the rats to gnaw on. The bread must not be moldy, though. Some rats also like pasta. This can be fed dry or cooked. No seasonings, sauce, or salt can be added though.

If the rat's diet is otherwise balanced, it may never need meat. However, occasional treats are ok. The meat should be cooked. No sauce, seasonings, spices, or salts can be added. Uneaten portions must be removed quickly to prevent bacterial or fungal growth. Meat bones are also great for gnawing, and the rats often enjoy chewing off the last remaining pieces of meat and eating the marrow inside. In addition to meat, many rats enjoy insects, such as meal worms or crickets. These can be fed live, or they can be killed. They can be frozen or boiled in water to kill them, and are available in most pet stores. Dairy is not needed by most rats, and should never be fed in large amounts. Contrary to popular belief, many rats do not like cheese. In addition, cheese can cause gas and diarrhea in rats. A little bit of dairy can be given. Pregnant rats need a bit of added protein and calcium. Some of this can be provided with bread soaked in milk. Yogurt drops are also a great treat that most rats enjoy.

Supplements are almost never needed, if the rat is on a balanced diet. Only multi-vitamin diets formulated for rats should be used. This is usually bought in a liquid form and added to the water.

Health

Rats are prone to some disease. Like most animals, they are not perfect. In particular, rats are likely to get tumors, especially mammary tumors, and respiratory illness, usually a flare up of mycoplasma which can progress to pneumonia. Rats can also become ill from certain strains of strep. These diseases can be fatal for rats, so it is very important to have a qualified, preferably experienced, veterinarian to treat your rats should they become ill. It is even more important to find this vet before the rats become sick. Most animals are known to hide their illness when they become ill. For this reason, it is extremely important to know your rat's personality characteristics. If the rat is not acting like itself, then it may be ill. In addition, symptoms can include, but are not limited to: sneezing, coughing, wheezing, noisy breathing/clicking, lack of appetite, dehydration, weight loss, lack of condition, dry and brittle fur or skin, unusual lethargy, puffed fur, hunched position, diarrhea, squinty or closed eyes, and excessive red discharge (called porphyrin) from eyes and nose. If your rat exhibits any of these signs, please seek help immediately. A healthy rat can live for 3 to 4, or even more, years. Illness can dramatically decrease a rat's life span. Tumors are quite common in rats, especially females. Rats can develop tumors at almost any age, but are most likely to develop them after the age of 2 years. Some tumors can be removed. This does put a lot of stress on the rat, however, and the tumor often grows back. Many rats can live with tumors, as long as the tumor is not painful, and remains relatively small. Benign tumors are the most common. These are harmless and can be identified as a soft, squishy, movable bump that is not painful and is not attached to any organs. Rats can develop malignant tumors too. These are harmful, and usually end up fatal. They are hard to the touch, cannot be moved, and are attached to organs. Several diseases can affect a rat's immune system. The most common is mycoplasma, which is said to be present in the nasal passages of all rats except some laboratory rats, but does not affect the rat unless its immune system falls below normal. This can happen as a result of stress, or as a result of another disease. To ensure the health of the rat's immune system, it must be kept on proper bedding. Pine and Cedar shavings should not be used with small animals. The oils in these woods can be extremely harmful, and have shown to not only cause respiratory stress, but has also caused liver disease. Proper ventilation is necessary. Rats can be kept in aquariums, but these aquariums must be kept clean because they do not offer the same ventilation cages do, and therefore allow ammonia from urine to build up. Rats should be kept away from temperature extremes, as well as sudden temperature changes. Vents and open windows can allow chilly drafts to come in, which can stress a rat. Most rats prefer an average temperature of between 60 and 70 degrees Fahrenheit. The maximum should be no higher than 80 to 85 degrees. To prevent illness, a rat's home must also be kept clean, bedding should be cleaned out at least once a week. Younger, older, and previously ill rats are particularly susceptible to disease.

Megacolon is another disease rats can have. A rat who has megacolon was born with the condition. There is strong evidence this disease is genetic, and can be inherited from two rats who do not have megacolon. For this reason, it is very important to know where the rats come from and their family history before even thinking about breeding them. Megacolon is a very serious disease, and is often fatal. Some rats with megacolon will die shortly after birth. Some will show no signs until they start to eat solid food. These rats will appear normal their first 4 to 6 weeks of life. As they start to eat solid foods, their bellies will become larger and larger. This happens because the rat lacks certain nerves in its intestines, and so food and wastes cannot be passed. If a rat is not euthanized, there is risk of the belly become so large that the intestines will rupture. Sometimes there will be so much waste products built up, that the rat will be able to release it as one big mass of watery diarrhea. There is no cure for megacolon, but there is possible treatment. The treatment is not always effective, however, and the rat can still die a painful death.

Rats can become injured like most animals. Most non-serious injuries do not need treatment, only need to be kept clean. Small cuts and scrapes should be immediately cleaned out with warm water, and kept clean. Bleeding from these can be stopped with some clotting agents, one very good product is called Kwik Stop. Serious cuts and scrapes should be seen by a veterinarian. Broken bones usually can heal by themselves, as long as the rat is kept quiet so it can allow the bone to mend itself. Rats are so small, a vet is usually unable to do anything about a broken bone, but just in case, it is a good idea to take the rat in anyways, or at least call the vet. Rats can also get abscesses. These should be seen by a veterinarian so appropriate treatment can be administered. These sometimes need to be drained and cleaned out daily, but a vet will be able to demonstrate the proper way to do this.

Rats do not handle hot temperature extremes very well, and are prone to heat exhaustion. The best way to cure this is to prevent it. Keep rats out of direct sunlight and away from windows. Also make sure they have plenty of water. Try to keep the rats quiet on hot days. Rats suffering from heat exhaustion are usually inactive, stretched out, does not respond, and panting or breathing quickly. A rat showing these symptoms should be moved to a cool area immediately. The rat should also be taken to a veterinarian. If a vet is not immediately available, keep the rat in a cool area, and put a cold, wet cloth near it to help lower its body temperature. If air conditioning is unavailable, a fan is a must. A shallow dish with about an inch of water can be provided as well, since some rats do like to go swimming. Plastic soda bottles can be filled with water and frozen overnight to provide a cool place for the rat to rest near.

A rat's teeth do grow continuously. Gnawing material must be available at all times to prevent the teeth from growing too long. Most rats do not have a problem with this, but some do. Overgrown teeth can be painful and make it hard for the rat to eat. In addition, overgrown teeth can grow into the jaws of the rat. A rat with overgrown teeth must be taken to a veterinarian to have the teeth clipped. Only a vet should do this.

Due to the fact disease can be so dangerous for rats, it is important to quarantine before introducing a new rat to resident rats. Preferably, the quarantined animal(s) should be in a completely different building. However, such a set up is not possible for everyone. So, making the best of what is available, the quarantined animal must at least be in a different room on the other side of the building. Be sure to wash your hands after handling the quarantined rat, and if possible, change your clothes. This helps to prevent any disease from passing to the resident rats. In addition, the new rat must be quarantined for at least three weeks, though the longer the better.

Behavior

Rats, like any other animal, do behave a certain way. They are extremely social, and have a very specific social ranking system. When two rats meet for the first time, they usually go through some minor fighting before determining who will be the boss. Rats should be kept in single sex groups of two or more. Even male rats are social and enjoy company. A rat who is by itself may become neurotic, developing disturbing behaviors such as barbering, in which the rat over grooms itself until it develops bald patches, or even self mutilation. The rats can be introduced to each other later in life, but it is always best to buy two at the same time. Female rats are easier to introduce and rarely get in a serious fight. Older male rats will usually accept a younger male quicker than another older male, because the younger male is less likely to fight or even challenge the bigger, older male. All introductions need to be monitored. Usually fights are not serious unless there is blood shed, in which case the rats will need to be separated immediately. A squirt of water can break up fights long enough to get one rat out. Before reintroduction, it is best to clean the cage thoroughly to remove some of the scent of the previous resident. Letting the rats meet in a neutral area, "no man's land," is also best.

Young rats love to play. They will wrestle, chase each other, and can sometimes be observed mounting each other. Wrestling and chase are not serious games to be concerned about, they are just for fun. The only time one needs to worry is when these games lead to bloodshed. Sometimes rats will get carried away and one may squeak, but squeaking in itself is not serious unless the rat is screaming non-stop at the top of its lungs. Mounting is usually done by males as a sign of dominance. Females will also mount each other to show who is the boss. Some females have also been known to mount when they are in heat. Social grooming is important to rats, and is a way to reinforce relationships. Rats are very clean animals, and can also be seen grooming themselves. Rats sometimes like to groom their human companion too. This is usually done in the form of licking, pawing, and even gentle nibbling. Some rats will groom the human, then sit and way for the human to groom them. This will go back and forth for awhile until one or the other decides they are done. The action really makes the rat feel better, and more secure.

Rats can be frightened fairly easily at times. Some rats are frightened by the scent of a strange animal, such as a cat or dog. Other rats do not like loud or strange noises, such as thunder, clanging pans, or rustling papers. A rat who is frightened will usually freeze in place, positioned ready to run. Their ears will be up and alert. They don't move a single muscle, but when the time is right will dash for a place to hide. If one rat takes this position, other rats in the group are likely to stop what they are doing and pay attention. Sometimes a rat will also start to tremble while holding this position. Rats who are frightened of being held or are frightened of people in general may loose control of bodily function and expel their wastes upon being picked up. As the rats are handled, they overcome this, but they need a lot of quiet, gentle handling and reassurance before they can do so.

Rats are also extremely intelligent creatures. They need a lot of stimulation in the form of toys and other rats. Most people don't expect young dogs to stay in a house without toys and not destroy anything, but rats are really the same way. Almost anything can be made a toy, as long as it is safe for the rat. Rats are also very easy to train. Like most animals, it is best to go in baby steps and reward the correct behavior. Most rats will pick up very quickly, and will learn to perform sometimes difficult and intricate tricks. When training rats, the sky is the limit, just be creative, but make sure it is a safe trick.

Rats sometimes grind their teeth, called bruxing. This behavior is not harmful, because the rat's teeth are constantly growing. This behavior can be described for several emotions the rat may be feeling. If the rat is nervous, it may brux. Aggressive or angry rats sometimes brux as well. Both of these two emotions coupled with bruxing have been observed in rats who have litters who are a little less than willing to allow the babies to be handled. A rat who's warning is not heeded will bite if it feels the need. This does not always mean the rat is aggressive or mean, but can still be serious and may even need a doctor's attention. Bruxing is also done by rats who are extremely happy and comfortable. Some rats will chatter away just as if they were talking. Rats who are boiling over with happiness may even pop their eyes out while bruxing. These behaviors are disturbing at first, but not harmful to the rat.

Handling

Rats need careful handling just like any other animal. A rat should never be picked up by its tail. This can damage not only the spine, but the tail itself. The skin on the rat's tail can be removed if it is held by its tail. The skin cannot be replaced, so the tail must then be amputated. The tail is very important to rats. It helps aid them in balance, it also helps them regulate their temperature. A rat should instead be picked up by its body, similar to the way a cat would be picked up. One hand should be used to go under the rat and pick it up. Both hands can be used to cup the rat to pick it up. Once off the ground, the rat can either stand on the hand, or be placed on a shoulder or in a lap.

Rats should not be allowed to travel in a car loose. Instead, they should be placed in a carry box during trips. It can be a simple cardboard box, or it can be a special carry box. Air travel cat carrier are often very useful for rats, and not usually too big. Any carry case designed for other animals should be inspected closely to ensure that it will not allow the rat to escape. While traveling in a hot car, air conditioning is a must. Rats can overheat easily, which can result in death.

Selecting a Rat

One of the more important decisions when buying a rat is choosing where to buy the rat. Pet stores are among the more common places to buy rats, however this is also one of the worst choices to make. There are some very nice pet stores that take care of all their animals, make sure the people buying know how to care for the animals, and make their profit off pet supplies not the animals themselves. These pet stores, unfortunately, are the minority. Most pet stores sell "feeder rats." Rats set aside as pets are often the same rats as the feeders. They are usually not tame, even if they act tame in the store they may come home and act frightened and nervous or extremely aggressive. There is absolutely no guarantee on health. Pet store rats are often bred without discrimination. As a result they have very weak immune systems, and often carry all sorts of diseases. They are also very prone to tumors. If a pet store is the only place to buy rats, one must look at all the animals in the store. The animals should be in clean cages, appear to be healthy, have food and water, and should have the proper food and bedding. The employees should also be interviewed and should be knowledgeable about the animals, and willing to answer any and all questions. A breeder a is one of the best sources for rats. However, this does not mean all breeders are responsible or care for the animals properly. Just like pet store employees, breeders should be interviewed. They should be extremely knowledgeable and should be trying to accomplish something in breeding rats. Breeders usually only breed the healthiest and friendliest rats. They should be more than happy to invite clients into their home to see their breeding operations. The rats from breeders are often friendlier and healthier. Rescues are another place to find rats. These rats sometimes come with behavioral or health problems due to neglect or abuse in their previous homes. With special care and attention, they can become the friendliest, most loving of pet rats. Also buy bringing home a rat from a rescue, one will be saving a life, especially if that rat came from an animal shelter that puts down animals that have been there a week or more.

Most pet owner would not dream of not having a veterinarian. The same applies to rats. Rat owners should have a veterinarian, at least for emergencies. The veterinarian should be chosen before an emergency comes up, however. Recommendations from other rat owners is a great way to find a veterinarian. If no recommendations are available, a phone book can also be used. All veterinary offices should be called up to make sure they have a veterinarian for rats, however, as some veterinary clinics do not take rats. When a veterinarian has been found, the pet rats should be taken in for a visit and general exam. This is a great time to ask the veterinarian questions, such as how long they have been treating rats, their experience, how they first became interested in rats, and more.

A very important decision when choosing rats is to choose a male or female. Both make equally nice pets. One of each should not be purchased and expected to live together. This will end up in many unwanted, unplanned for pregnancies, and could result in unintended neglect or death of any of the two parent rats or the babies. Males and females kept in the same household should be housed separately. Females tend to be more prone to tumor than male rats. Male rats, once they have aged and matured, tend to be a bit calmer. Females are extremely active and inquisitive. They love to explore and are constantly on the move. Some have been known to be a bit high strung, but good breeders work to breed this out of their lines. Both males and females are friendly, can be taught tricks, and are equally easy to care for.

Another decision to make is age. Younger rats have a longer time to live, and are often more playful. Younger rats can also be so interested in play, they ignore their owner unless their owner is playing with them. Older rats will have a shorter time with their new owner, but can also be calmer and more willing to sit still to be pet. Both older and younger rats can be taught tricks, and are equally likely to be friendly.

Rats come in a vast variety of colors and markings, as well as coat and ear variations. The most commonly seen rat is the normal fancy rat, also known as standard rats. They have straight fur, and normal ears. Rats can also have rexed coats and dumbo ears. There are also manx and hairless rats. Theoretically there is no difference in temperament between these variations. Some people do insist, however, that rexed and dumbo rats are friendlier and calmer than standard rats. As a general rule, however, all rats, regardless of coat type, ear type, and whether or not they have a tail make great pets. Colors and markings do not make any difference in temperament of the rat, but are simply a personal preference of the owner. Two of the more common colors are black and agouti (wild form brown). Some of the more common markings are berkshire (white belly and feet) and hooded (colored head with colored stripe down the back). Hooded rats are often mismarked, meaning the stripe down their back is broken, jagged, or otherwise imperfect.

Choosing a rat is very important. All rats in the colony should be examined. If one rat is sick, it is likely the others are sick, or at least carriers, even if they do not show symptoms. The rat should be alert and responsive. Its eyes should be clear and clean, it should breath easily without wheezing, and it should not be sneezing. The rat should not run away or be frightened when handled. The parents of the rat should be equally healthy and friendly.

Breeding

Anyone thinking of breeding any pet should first own the animal as a pet first, for at least several years. This will allow the person to find out what it is like to care for that animal, what the animal itself is like in behavior, what kind of care that animal needs, and get an idea of what it may be like to breed the animal. Breeding is a very expensive hobby and will not make any money. Good breeders are lucky if they break even with the animal they sell, let alone make a profit. Breeders who make a lot of profit off the animals are usually making sacrifices in the animal's care and health. All animals should have appropriate housing and supplies, and should have a proper diet. All breeders should have a goal too. The two animals being bred should be special. They should not just be friendly, but should be the friendliest of the friendly. They should also be extremely healthy. Good conformation, markings, and colors are also things to look at when choosing breeding stock. Anyone thinking of breeding must have a veterinarian. Most animals can deliver without complications, but it does not always work that way. Sometimes emergency cesarian must be performed. Without this, the mother and babies will die. There must also be a market for rats. If there is no one to buy rats, then the breeder will be stuck with all the babies. The breeder should also be familiar with diseases and complications common to rats. The breeder must familiar with all aspects of breeding. Breeding is not simply putting two animals together to get more animals. A lot of work is involved before, during, and after breeding the animals, and even more work throughout the mother's pregnancy, birth, and weaning. Lastly, the breeder must be willing to take responsibility for all rats bred. A rat can easily have 20 or more babies in one litter, the breeder must either have serious homes for all these babies, or be prepared to care for all the babies. When deciding to breeding one must know the difference between males and females. This is easy enough when the animals are older, but the breeder must be able to tell the different while the rats are young too. There are all too many stories of people who want a male or female rat, go to a pet store and have the employee help them, and are given the opposite. Neither they nor the employee knows the difference until it is too late. The person ends up with either a pregnant female, or ends up impregnating their current female when bringing her a friend they thought was another female. Experienced breeders can tell males from females the day the rats are born. Typically, the anus and genitals is further apart on males than on females. As they get older, the male's testicles become visible as well. Around 3 weeks of age, the owner should be able to tell males from females. At about 5 weeks of age, the boys in the litter should be separated from their mother and sisters to prevent unplanned litters. Male rats should not be bred until they are at least 6 months old. this gives them time to mature, but also lets their true nature shine through. Male rats may act sweet and friendly until they are 6 to 8 months old, then the testosterone in their system can cause them to become unruly and aggressive. A rat who is aggressive should not be bred. The offspring may end up perfect, but the offspring may not end up perfect. It is always best to wait and see. A female rat should not be bred for the first time until she is at minimum 3 months old. It is best to wait until she is 4 to 8 months old. It is always best not to breed a female for the first time after she is 10 to 12 months old. A female rat will go into heat every 4 to 5 days. During this time she is sometimes nervous and high strung, even if she is normally calm and friendly. She may also be friendlier than normal, and can sometimes be observed displaying herself. If touched on her lower back, she will freeze. If scratched around the base of her tail, she may also flatten out her back, raising her hind end, and move her tail to the side in preparation for the male. Her ears may also start to flap. Pregnancy for rats is about 21 to 23 days. A rat may start to show pregnancy a week before the due date, or she may not show until a few days before the due date. Baby rats should be left with their mother for at least 4 weeks, 5 weeks being better. After being weaned, all babies should be placed with an older rat. This allows them to learn how to be rats, including rat socialization and body language. The older rat also can help to teach the babies their manners. If the babies were not handled while they were young, the older rat can teach the babies to be friendly. Older rats make wonderful teachers and role models for babies. Before breeding, please be sure to think it through thoroughly. Keep in mind these are living creatures who need love and care.