dogs winter coat

Question
howdy!  Our family just moved up to Alaska and we are trying our best to adapt to the climate.  Our family includes two small mixed border collies.  I am unsure what they are mixed with, and their winter coat is looking sort of meager.  My basic questions are: 1)  what environmental factors make a winter coat start growing and 2) what can i do to give them the best possible winter coat.  3) considering the answers to these questions, would keeping them inside the house at night hinder their coat growth? (i.e. warm temps stunt fur growth).  any help would be appreciated, thanx -steve

Answer
It actually has nothing to do with the weather-it's the length of day light hours that cause the fur to grow a bit thicker

Even short haired dogs that have always lived in Alaska will always have sort hair,so there isn't anything you can give them to make there fur thicker or longer-it's genetic

You don't want to keep dogs outside at night in the cold-in some places you could end up being in trouble with the local SPCA(unless they are sled dogs)

Something that might help though are coats made for dogs-they aren't just for small dogs anymore,dogs as large as great danes can wear them,and you can get them at any petstore-you may want to bring your dogs so you know what sizes to get