When I looked up my (mini) Italian dictionary under the entry for "lend" it had a sub-entry: "lend a hand" (fig) dare un mano
Given that "lend me your ears" is also a figurative phrase I thought to follow the example of "lend a hand" rather than using the main verb given for lend (prestare). But of course the beauty of idioms is that they don't necessarily follow from logical reasoning so chances are it's something else entirely...
la mucca = the cow
Female singular nouns ending in -ca (mucca=cow) form plural by changing the ending in -che (mucche= cows)
btw I also suggest these two dictionaries:
"A vacca is, in general, any adult female bovine, while a mucca is a vacca which is giving milk. Mucca was originally a local, Tuscan term. However, vacca is also used as a derogatory term for a female human, so it's sometimes avoided, even though it is more correct when not talking about milk production."