for what price? how many animals are worth one walking human?
I honestly can't comprehend the alternative. You'd walk up to some poor sap paralyzed from the neck down and say "Gee I'd really love for you to walk again but I'm a little bit more concerned about the pigs and monkeys?".
And I wish we had a better way, but we just don't yet. Bioinformatics is working on creating virtual bodies, but we're not there yet, it's decades away.