I started a post on this last year cause I did not know much on High Altitude Disease (Brisket Disease). But I am a 4-H leader and had a girl that bought 2 red Angus steers in Kansas last year and brought them back to Wyoming, she lived at approximately 6,500ft altitude. Both of her steers got it and died. People posted that it is more common in steers than heifers and once they are past a year old, it is less common. But I would watch her close and see what your vet thinks after you have her tested as your vet probably deals with it being in that altitude. Anyway, you are much higher than she was and she had 2 die, something to think about. Her 2 steers lived for a week and she went out to feed in the morning and they were both dead, her vet came out and said it was brisket disease. I live at 5,300ft altitude and have not had anything happen to anything I have brought back but you are almost 3,000 ft higher than me.