As an owner of one Border Collie today, and having had two Siberian Huskies in the past, I may have some tips for you.

First, the dogs are far too young to use in pulling sledge or carrying backpack. Wait until they are two years at least for pulling, two-and-a-half for carrying. Until that, let them play and have fun.

My BC is big and has long fur. The only winter problem is that the hairs under the feet (between the toes) on -4c and newly fallen snow will turn into ice lumps. The best way to remedy this is a round with the haircutter. I cut the hairs before long trips as a general rule. The SH's never had this problem. Some use oily lotions, but I've not found them as useful.

My BC never minds -20c as long as it does not blow too much. But he is used to stay outside much. For short haired brands you must pay attention to keeping them warm. A good mat and a cover will suffice. Some have warm coats for their dogs, and it might be a good idea at night at least. Usually even short haired brands are so active that they do not freeze as long as they are running.

Some dogs get sore feet, especially on ice-crusty snow. To prevent this the only way is training and running so the feets are strong. To cure it if it happens, take some dog socks with you on the trip. I do that, but up till now I've never used this. You may see some pictures of my dog in winter conditions in this forum in the tread Far North witer trip report. Correcton, I just saw that you've read it.

/Otto