Your silver piece was actually made by Gourdel, Vales & Co. The "Y" is actually a "V" out of Birmingham, England. The date sounds right, as they were operating in the first part of the 20th century. As for the boar, I have never seen that before. My educated guess is that it may be a symbol added at the request of the client it may have been made for. An identifier, like a coat-of-arms, that would be the symbol of a noble house, family symbol, that sort of thing.