This is a very important point that I think needs to be discussed. As someone who is an animal advocate, you might think that I would be against all animal experimentation. However, I am not. It would be great if we were all Christ-like and actually wanted to sacrifice for the greater good regardless of our own suffering. But the reality is that we do not. So hear me out.
As always, my ethics depend on the golden rule and Utilitarianism/Least Harm Principle. Right off the bat, some tests do not violate the golden rule at all. If we have a mouse running through a maze to get some cheese, this really does not violate the golden rule. If there is a detectable amount of physical or mental pain inserted into the experiment, it violates the golden rule. So I have three internal metrics I follow to determine whether the experiment is justified:
1) Have all alternatives been demonstratingly ruled out. The Johns Hopkins Center for Alternatives to Animal Testing is a great resource though there are many more. Examples of this include how we used to kill a rabbit every time we wanted to see if a woman was pregnant. Now we have pregnancy tests. Another example is how we used to send pigs through car crashes. Now we have crash test dummies that are far more advanced than the old method without the suffering.
2) If there are no alternatives available, we must study the animals and quantify the amount of pain involved. We must ask what they would want. Since we are following the golden rule, we must imagine what it would be like to be them going through this experiment after asking what they want and do not want. Equal consideration is given. However, since empathy is difficult for people to even give to other people, we should encourage others to question whether they would perform the experiment on a newborn child. Newborn children can be far less mentally advanced than many animals. Since human children are less mentally aware yet are so valuable at the same time, it provides a good way to determine if the golden rule should be broken. Most people feel obligated to take into account the moral consideration of the child. If we are being unbiased, we would take equal consideration of the animals.
3) If you would still break the golden rule, we must demonstrate that the greater good will win. That the probable outcome of the experiment will yield better results than if we did not, but taking into account equal consideration of interests.
Some people will say that animals saved their lives. That if we did not experiment on them, you would not be here today. But if the animals truly saved your life, don't you owe it to the animals so that no other animals ever have to suffer again?