**7. Ethical considerations animal models**

If acute pain models or acute pain tests are used in which the pain does not end with the animal's response, the pain should be terminated as quickly as possible. This may mean that the animals must be humanely euthanised as soon as the test is completed (for example, convulsive test) or that analgesics must be administered. Hence, it would be preferable to use avoidance tests rather than tests in which the pain continues after the results have been obtained. Animal testing contributes to life-saving treatments for humans, and in some cases, animals must be used because it is possible that early experiments could cause catastrophic harm if conducted directly on humans. But as cruel and inhumane as animal experiments seem to be, everyone is aware that no animal leaves the laboratory alive, and during most studies, the animals are killed and ultimately dissected. This is why we, as researchers, must use animals in research and teaching, responsibly to protect animals from unnecessary pain and suffering. Researchers should also avoid exposing the animal to stress and fear, which can result from the method of conducting experiments. The number of animals involved should be as minimal as possible, and it is desirable that the duration of the experiment be as short as possible [81].
