When the late Hysson started upchucking his food during my 2010 trip to the Wind Rivers, I finally figured out that he was first gulping lots of water really fast and then eating his food too fast, and it was mechanical (too much air swallowed with first water and then food). My-daughter-the-veterinarian suggested that in future I feed him small amounts 3-4 times per day while on trips, and let him drink only a small amount of water at a time, especially in the morning before breakfast. Altitude didn't appear to be a factor, but the dry air (giving him an immense thirst overnight) certainly did!
Assuming that you are taking reasonable steps to acclimatize yourselves, that should work fine with the dog.
Edited by OregonMouse (04/15/16 03:18 PM)
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey