Two trail-weary puppies flop in the snow after their first run in harness behind a veteran leader. Gone are the days of carefree romping alongside an adult dog team - an exercise allowed by trail-wise drivers to strengthen puppy legs and toughen the pads of their paws.

Since this is the pair's first day on the trail, a part of their apparent exhaustion may be from getting tangled in their harnesses. Harnesses are made of webbing, and puppies have to be trained not to get tangled in them or chew them to pieces. These pups - around seven or eight months old - will need new and larger harnesses as they continue to grow.

- Fred Machetanz