You probably mean sapience and not sentience, because dogs and monkeys definitely can feel things.
I'm going to give an opinion that some may not agree with. The most ethical form of eating meat is from an animal that can consent. Since we can't ask a dog, monkey, cow, pig, etc. if they want to be consumed, the most ethical meat is humans who consent to it. If you disagree please explain how.
The same goes for sending things into space to die for us.
What if I just don't care. I'm against needless cruelty, but for the near future we will need some amount of meant (until correct substitutes are found). The things bred for centuries to be meat will continue to do so for the near future, until we have the time and effort to spare in order to change it.
As someone above pointed out to me, the testing nor space deployment of animals was not truly necessary for any data, its all needless cruelty that gives no results. That practice should be ended.
if humans can only progress into space by first kidnapping animals, then they don't deserve to see the stars.
Indeed; I'd have happily volunteered instead of a monkey or a cat for such an endeavour for the benefit of our species; and I'm sure I'm not the only one. There's something far more moral about testing such things with people fully aware of what they're doing and the risks compared to sentient beings not comprehending what's happening to them and likely being in a panic all along the way. There should be a word for it, really.
Damn morally superior people always mentioning their moral superiority while making a morally superior argument. Let me eat my eggs in peace (I still eat eggs but I promise only from farms that have lots of space for their chickens, I'm almost there comrade)