But then there would be no cows.
Pugs are my favorite example-- always in respiratory distress, abnormally short life spans, and unable to normally reproduce.
It isn't some kindness that we create pugs the way we do-- just a gap in traditional morals.
We may confront this more should we find we've created an intelligence with the capacity for emotions.
One could make the argument that evolutionarily speaking, being domesticated (usually then eaten) by humans is the most reliable survival strategy for any species.