Dear Gents,
for hydro test, if i use a brand new pressure gage, is the calibration required?

yes. unless it is a master gauge with certified report

I concur with TonyQ...

Information will state certifying company, date certified, date due and s/n. Your QA/QC manual should have a Calibration Log book to show all gauges, their location and date due. We also keep a record of calibration of our torque wrenches there.

Yes like any other pressure gauge used for hydro. Let me add my two cents of wisdom: use always two pressure gauges during hydro. If the only one you are using sticks you might damage people and property. When using two pressure gauges you may detect if one is out of calibration.
Mind that if you detect a pressure gauge out of calibration during the usual calibration all pressure tests since last positive calibration have to be re-considered.
mauro