Why should'nt an animal be use for scientific research

please give answer to why not.and an example

Because it's torture for them. They are living creatures and feel pain. And we distribute it for reasons that aren't even worth it. Humans and other animals are legitimately, biologically different compared to humans and react differently to experimental treatments. It can be argued that it still helps but we use them SO EXCESSIVELY. It isn't humane. There is no way you can say that it is. We should be to the point where we are so technologically advanced that we shouldn't have to subject animals to TORTURE.

Torture: the act of inflicting excruciating pain, as punishment or revenge, as a means of getting a confession or INFORMATION, OR FOR SHEER CRUELTY. (dictionary.com)