What? Children aren't a different animal,though. They're humans. They will eventually grow to adulthood.
An animal will always be an animal. Are you going to go tell lions not eat the gazelles because it's mean? Will you pull the remora off the sharks and stick them watermellons and teach them to be vegan too?
Absolute toss, "We have a responsibility to the animals". No we don't.
We SHOULD treat them with respect. But we can also used them as beasts of burden, as companions, and if necessary as raw supplies for food and materials.
You don't get to cry and while about horse racing for the same reasons rabbits don't get to cry about the hawks. If you didn't want to be food, you should have evolved faster.