It's true that the "ele" ending usually denotes plural, in feminine and neuter nouns. But there's a (small?) group of masculine nouns, (I think all those) ending in "e", like "câine", which form the articulated singular by adding "le". "The dogs", on the other hand would be "câinii".
Other masculine nouns like this include:
castravete, fluture, frate, iepure, pește, șarpe, șoarece, strugure