When you’re very hungry, you might say that you could eat a horse, at least in English. If you translated this or other idioms literally into other languages, people might not know what you were talking about.
Spanish speakers also talk about horses when they’re really hungry – Estoy tan hambriento que podría tragarme un caballo (I’m so hungry I could eat a bull), although in Argentina they say – Tengo tanto hambre que me comería una vaca entera (I’m so hungry I could eat a whole cow).
In French it’s a bull rather than a horse that people claim to be able to eat when they’re famished – Je mangerais un boeuf. Or you might have the hunger of a wolf – J’ai un faim de loup. In Canadian French they do talk about horses when hungry though: J’ai tellement faim que je pourrais manger un cheval avec ses fers (I’m so hungry I could eat a horse with its horseshoes on), or even elephants: J’ai tellement faim que je pourrais manger un éléphant.
In Italian the equivalent expression is: ho una fame che mi mangerei un bue (I’m so hungry I would eat an ox).
Portuguese speakers talk about eating horses or oxen: Tenho tanta fome que comeria um cavalo (I’m so hungry I could eat a horse), or Tenho tanta fome que comeria um boi com guampa e tudo (I’m so hungry that I”d eat an ox with horn and everything). They also say, Estou com uma fome de leão (I’m hungry as a lion).
In German hunger, bears and wolves go together: Ich bin so hungrig wie ein Wolf (I am as hungry as a wolf) or Ich habe einen Bärenhunger (I have the hunger of a bear.
Czech speakers get so hungry that they could eat nails: Mám hlad, že bych hřebíky polykal(a)! (I’m as hungry that I should swallow/gobble even nails!).