AY Honors/Small Mammal Pets/Answer Key
Fancy mice ("fancy", in this context, means "hobby") are domesticated versions of the common or house mouse (Mus musculus).
Physical description
Fancy mice is a term to describe mice that have been selectively bred for pet or show. They can vary greatly in size, from small pet mice that are approximately 16-18 cm (6 inches or so) long from nose to the tip of the tail, to show mice that measure 30cm (12 inches) nose to tail. Pet mice weigh about 25-40 g but large show mice can weigh up to 100g. As fancy mice have a different process of natural selection than their wild cousins, they come in a variety of colours and patterns. These include black, chocolate, blue, white, cream, lilac, red, fawn, champagne, cinnamon, golden agouti, silver agouti, silver and dove. Female mice are called does and males are called bucks. If well cared for, a mouse lives for around 2 years on average, with some reaching 3 years old.
Mice as pets
Mice are kept as pets in many countries for a number of reasons. Fancy mice are small, inexpensive, clean, and generally have a good temperament. Female mice are popular with many owners since they tend to cohabitate with other mice better than males. Additionally, the urine of female fancy mice does not contain as strong of an odor as that of the male mice. Bucks can fight with each other, unless they are introduced at a very young age, and they produce urine with a strong, musky smell. Some people, however, prefer the personality and curiosity of male mice. It is a good idea to keep fancy mice in groups of at least two if possible, as mice are sociable animals. However, if a buck and a doe of breeding age are put in the same cage they will produce a new litter every three weeks until separated.
Caging
Mice should be kept in well-ventilated areas. Fish tanks or cages with bars and plastic flooring make good housing. Give attention that the distance between the bars is under 9mm. It is a problem for young mice to force themselves through a cage with wider bars, and it's dangerous when they get stuck there.
The best products for in-cage bedding are aspen wood shavings or a commercial paper-based material. Despite popular belief, mice can be given newspaper for nesting, as the ink is soy based and nontoxic. They should not be given cedar shavings, as the oils in the wood are unhealthy. Small hide-aways and toys (such as a cardboard tube) are good to have in the cage. Commercial toys are also available.
Cat owners must also take special precautions to ensure that the mouse's housing is secure, as even the friendliest of domestic cats have been known to torment, kill and eat fancy mice if given the chance.
Feeding
Food for fancy mice is relatively inexpensive. Veterinarians generally recommend a product called lab block, a scientifically-formulated blend originally designed for mice in laboratories. Dry dog food is another good option when lab block is unavailable, as it offers balanced nutrition for a mouse and helps keep their teeth conditioned. Special mouse food found in pet stores also makes a good diet. In order to keep variety in their diets, mice can also eat oats, oily seeds, clean egg shell, breakfast cereal, and stale bread. Fruit and vegetables can be offered occasionally. They should also have clean water at all times and some sort of chewing wood in order to keep their teeth from growing too long. You probably shouldn't use any wood from the ground.
Breeding mice
It is important to consider breeding carefully and thoughtfully due to the rapid reproduction rate of mice. Adequate housing for the young should be available.
Female mice should not be bred before 12 weeks or after 8 months; doing so can be very dangerous, and some mice can die while giving birth. Bucks and does should be housed in separate enclosures until breeding is desired, at which point they can be placed together. The doe should be placed in the buck's enclosure, otherwise the doe will fight with the buck to defend her territory. Does come into heat around every five days, so the pair can be kept together for up to ten days.
A pregnant mouse will grow very round near the time of birth. The gestation period is approximately 18 to 21 days. Typical litter size is 8 to 12 young, though it can be more. It is best to remove the buck otherwise he will mate with the female as soon as the first litter is born, putting a huge strain on the mother, the unborn litter, and the new babies.
Baby mice, also called pups, are born blind, naked, and deaf. Their eyes are closed and their ears are stuck to the sides of their heads. After giving birth the mother should be left alone for a while, otherwise she might panic and eat the pups. She might also eat any dead or sickly offspring.
Pups begin to grow hair at two to four days. Ears open at three to five days, and the pups will start vocalizing. Eyes open at 14 days, and the babies will start exploring the world around them. At three weeks old they look like miniature versions of adult mice. At four to five weeks the pups should be separated from each other, otherwise they will breed with their siblings.
Mice clubs
Many fancy mice clubs have been set up around the globe. Shows are also held so owners can display their mice, where they are judged on color and behavior.
