I have 2 dogs Labradors(60kgs & 30 kgs each) I want to take them from Hyderabad to Gwahati. Trains? Airline?

You should but you have to take permission from the airline or railway authority. It will cost you a little bit more. But I think that doesn't matter when you are thinking about two of your best friends. It will take a very lengthy time by train. It will irritate those sweet little friends. I think don't torture them please go by Plane. Talk to Airline Authority. Do the needful and take them away with you.