模式动物,实验大鼠 z-bo 2020-07-27 739

　　Rats, rodents, Muridae, and Rats are variants of wild brown rats (Rattusorvegicus). It is native to the temperate regions of Central Asia and the former Soviet Union. It was imprisoned in the late 18th century and was first used in psychology research in the mid-19th century. In 1906, some of these rats were sent to the Vista Institute in Philadelphia (Philadelphia) to raise Vista rats. Since the 20th century, rats have been used in various fields of life science research, especially in the fields of oncology, pharmacology, endocrinology and nutrition.

　　Section 1 Biological Characteristics

　　1, general characteristics

　　1. Rats have a soft temper and are easy to be caught. Normally, they do not chew actively, but if they are not handled properly or lack nutrients, they may have seizures or bite. Female lactating mice tend to attack humans. After mating, adult male mice bite each other and even die in the same cage.

　　2. Rats are omnivorous and have the habit of drinking at any time. Even the same kind of meat likes to eat cooked animal meat (such as rabbit meat). Sensitive to malnutrition, especially the typical symptoms of vitamin and amino acid deficiency. Riboflavin deficiency, dermatitis, hair loss, physical weakness and growth retardation can also cause corneal neovascularization, cataracts, anemia and medullary degeneration. Vitamin E deficiency causes a decrease in fertility in female rats, while a severe deficiency in male rats causes a decrease in lifelong fertility.

　　3. The activities of rats are mainly concentrated from dusk to early morning. During the day, the eyes are usually kept in cages during the day, and mating usually takes place at night.

　　4. Rats are very sensitive to dust, ammonia, hydrogen sulfide, etc. in the air, and are susceptible to respiratory diseases. Respiratory diseases are usually the main cause of death in pre-b rats.

　　5. Rats are very sensitive to various stimuli. Rats may also respond to small changes in environmental conditions. The strong noise may cause the rat to panic and even bite each other. Offspring female rats may feed on infants.