The lastest non-human variation data release is available at EBI/EVA.  The release will consist of a collection of files organised by species that list all the RS IDs for variants stored in the European Variation Archive. The files include current RS accessioned variants in use, deprecated IDs, as well as unmapped variants. They can all be found here: 
ftp://ftp.ebi.ac.uk/pub/databases/eva/rs_releases/release_0_preview/

More information regarding the format of the general release can be found in the ""README_general_info.txt"", while species specific information can be found in ""README_species_issues.txt"".
 

Older dbSNP archived data are available 'as-is' and no longer maintained by dbSNP is available here ftp://ftp.ncbi.nih.gov/snp/organisms/archive/.