If you buy Antibodies supplied by Bioassay works they should be stored frozen at - 24°C for long term storage and for short term at + 5°C.
About
Rats are used to make rat monoclonal anti mouse antibodies. There are less rat- than mouse clones however. Rats genes from rodents of the genus Rattus norvegicus are often studied in vivo as a model of human genes in Sprague-Dawley or Wistar rats.