using multiple ssh private key files

There is situation where I have to convert development enviroment from one machine to the other. It includes transfer ssh private key file to new machine. Then, I have to seek solution for having multiple ssh private keys. It is very simple. What I need to do is edit ~/.ssh/config file to have multiple lines for IdentifyFile as below,

IdentityFile ~/.ssh/id_dsa
IdentityFile ~/.ssh/id_dsa.1
IdentityFile ~/.ssh/id_dsa.2

In fact, I just follow this link to get job done.