A change of direction for the 5th day of Christmas.

William S. Baring-Gould suggests that the presents sent on the first seven days were all birds—the "five gold rings" were not actually gold rings, but refer to the five golden rings of the ringed pheasant. 

Others suggest the gold rings refer to "five goldspinks"—a goldspink being an old name for a goldfinch; or even canaries. 

However, the 1780 publication includes an illustration that clearly depicts the "five gold rings" as being jewellery.

(Source: Wikipedia)