**IF** you think that we humans should not do stuff that harms or discomfits 'lower' forms of life... whether eating them or performing tests on them or hunting them - or whatever - I would ask: When did this rule or admonition arise?
After all, we are descended from omnivores who have been hunting and eating other species... and sometimes our own... for several million years. Chimps are known to attack and kill and eat members of other chimp clans. It is a serious issue to assert that we should NEVER do certain things, although we should have learned that, apart from the moral issue, it is simply not ultimately advantageous to hunt & kill wantonly and with no restraint. The Indians(Native Americans) of the plains saw so many bison that driving a herd over a cliff 'seemed' like a less dangerous way to hunt... but that plus white hunters almost wiped out the bison.

   Too many moralistic ideas seem more like simplistic slogans rather than reasonable, completely thought out concepts.

I, however, DO see a value in mitigating as much as possible any pain or fear in ANY other being that we feel the need to use for our purposes.