Does LCD panel have serial number on? How can i tell is my lcd panel original?

The only serial number Apple refers to in exchange/repair programs are your computer's serial numbers.

If concerned about a specific LCD's serial number, look at the serial number of the computer:

http://support.apple.com/kb/HT1349

You can use this tip to find out the age by time of year of your model:

https://discussions.apple.com/docs/DOC-6413