eh, dairy cows are slaughtered at 4-6, and they're the oldest animals to be slaughtered. Most animals are MONTHS or WEEKS old. not years.
Also, male chicks are macerated (mashed up alive) at just one to two hours old, because they're "useless". THey won't ever lay eggs, and they won't grow big enough to be worth it for meat chickens, so they're mashed up alive at a few hours. This is what you support when you support animal ag.