Sika deer are small to medium-sized deer, with a body length of generally 125 to 145 cm, a tail length of 12 to 13 cm, a shoulder height of 70 to 95 cm, and a weight of 70 to 100 kg.

The coat color of sika deer is chestnut red with many white spots resembling plum blossoms in summer, while in winter, their coat color changes to brown, and the white spots are not very obvious.

Sika deer are mainly distributed in Japan and live in grasslands and woods. They are docile, timid, and easily frightened by the slightest sound. Their slender legs make them faster when running, and they are very good at jumping.

Most deer have white spots when they are born, but they disappear with age. However, the white spots on sika deer remain because they help the deer hide in the grass to avoid predators.

Sika deer do not live in groups. They are active in the morning and evening and their living areas change with the seasons.

In spring, sika deer mostly move on semi-shady slopes, move to forest edge areas on shady slopes in summer and autumn, and prefer to live on warm, sunny slopes in winter. Sika deer mainly feed on grass, fruit, herbaceous plants, tree buds, trees, and crops.

Male sika deer have large, long horns with four forks, which are their fighting and defensive weapons. Therefore, stags will often rub their antlers vigorously on tree trunks to remove the outer layer of skin and sharpen their horns.

Male deers molt each spring, and the long old horns fall off. The newly grown antlers gradually harden and grow longer. In autumn, the outer skin of the antlers dries up, and the inner structure is fully grown.

Generally, according to the formula for calculating the lifespan of mammals, a 20-year-old sika deer is equivalent to a 250-year-old human, and a 30-year-old sika deer is equivalent to a 370-year-old human.

The average lifespan of sika deer is about 20 years, which is considered a very long lifespan among mammals.

Adult sika deer breed once a year. From September to October every year, male sika deer will mate with multiple female deer. The gestation period of female deer is about 30 weeks, and they breed from May to June of the following year. Each litter has one calf, and it is rare to give birth to two offspring.

Fawns weigh about 4.5 to 7 kg at birth, grow rapidly, are weaned in late summer, become independent at 10 to 12 months, and reach sexual maturity at 16 to 18 months.

Free-range sika deer can find medicinal materials to eat and self-regulate, so sika deer have extremely high nutritional and medicinal value. Sika deer are also the only mammal that can completely regenerate organs.

The body of sika deer contains a large number of active factors in the form of active factor clusters. These clusters help sika deer effectively maintain cell vitality and promote the regeneration of their own organs.