Empathy is the ability to mentally & emotionally connect to another being.
The inability to experience empathy is a trait of a psychopath. I think that avoiding cruelty towards other living things is a primary moral rule. However, I'm also a realist. I know we live in an insane world, where unimaginable suffering exists all over the globe, at all times.
I think that keeping sentient wildlife encaged & tortured in experimentation is immoral, regardless of the scientific value. The whole issue of factory farming is another animal issue I'm not going to get into now, but generally we should be finding ways to reduce suffering, not increasing it.
Anyway, this story about lab chimps being outside for the first time is proof that these animals are consciously experiencing life basically the same as we are. They are feeling, seeing, hearing, and reacting to their situation. To inflict prolonged pain on such creatures is not justifiable & can't be good for the soul.