My lab just turned one on the 23rd and she didnt go through her first hear until 11 months between 9-12 is about normal from what i know for the first time. Letting them hunt and train want hurt them a bit they might get a little moody (like our wives :help: ) but just be patient during this time. I just keep mine in her kennel when she is in the house most of the time when she is in heat. They will bleed some small drops when they get up and start moving around a good bit, so only let her free rome in the home for short periods. As far as the time is it usally last a couple weeks but you should keep them away from male dog to be on the safe side a good month from when they start b/c even though they stop bleeding and everything goes to looking normal again they still can get pregnant.