I recognize the value of these studies but I don't think they're worth the pain and distress inflicted on these animals. I can't put myself in the place of the

I recognize the value of these studies but I don't think they're worth the pain and distress inflicted on these animals. I can't put myself in the place of these researchers and see myself injecting things that cause harm to the rats without feeling really shitty about the situation. Are they just numb to what they're doing?