LIFE CYCLE:The gestation period is about 19–21 days, and they give birth to a litter of 3–14 young (average six to eight). One female can have 5 to 10 litters per year, so the mouse population can increase very quickly. Breeding occurs throughout the year.
New born males and females can be distinguished on close examination, the anogenital distance in males is about double that of the female. From the age of about 10 days, females have five pairs of mammary glands and males have no nipples.
The pups are born blind, defenseless and without fur or ears, they do not have the ability to see. The ears are fully developed by the fourth day, fur begins to appear at about six days and the eyes open around 13 days after birth; the pups are weaned at around 21 days. Females reach sexual maturity at about six weeks of age and males at about eight weeks, but both can copulate as early as five weeks. If the infants live in high temperature areas from the birth, they will become lesshaired. They are having a pointed snout, a pointed nose, long tail, small rounded ears, and a long naked or almost hairless tail. When the nursing is over, regardless of their sexes, both the males and females begin to chew on your food and possessions. The tail is also used for balance when the mouse is climbing, walking, fighting, running or as a base when the animal stands on its hind legs and to convey information about the dominant status of an individual in encounters with other mice.
Adult house mice have a body length of 7.5–10 cm and a tail length of 5–10 cm . The weight is typically 40–45 gms. In the wild, they vary in colour from light to dark light to dark brown. But domesticated mice are produced in many colors ranging from white to champagne to black. They have short hair and have a light belly. The ears and tail have little hair. The hind feet are short, just15–19 mm long; though they can jump vertically. They are found in and around homes and commercial structures, as well as in the open fields and agricultural lands.
House mice usually live less than one year in the wild, due to a high level of predation and exposure to harsh environments. However, they often live two to three years. Domesticated Mice can live less than Four years.