Have I mentioned the cows?
There were thousands of them on this ship alone.
Part of your brain must be churning away on this idea right now, pondering why unlike any good science fiction story humanity loaded up thousands of cows onto a half dozen space freighters and shipped them off into the waiting universe as we fled a dying Earth. Why live cows? Why not thousands of cow embryos or some kind of magic genetic synthesis thingamajig that would solve all our problems of food supply at the other end of the galaxy? Why live cows?
When push came to shove and every resource of the failing planet was thrown unflinchingly at escape, it turned out to be the easiest solution. Big cargo transport ships, refuge class heavy cruisers, with loads of fuel and loads of space and the lowest tech, get the hell out of dodge approach that humanity could muster.
Live cows were ready and — well, they went.