Translate the following English sentence to French:
"Now, however, we need a system that involves stating where the animals come from, where they were born, where they were reared and where they were slaughtered."
Mais nous sommes au contraire obligés d'appliquer un système qui suppose que l'on mentionne d'où vient l'animal, où il est né, où il a été élevé et abattu.