German Shepherd Health Problems Please Help

Question
Hi  I have a 10 year old senior German Shepherd female Dakota.  Very good health up to a week ago.  I took her to the vet when I noticed her straining to go to the bathroom outside.  I thought it was constipation, so changed to soft food.  Vet noticed loose stools on examination.  Medication was given to stop this.  Stable for two days, with some stomach heaving and straining.  The evening of the seconday day laboured breathing, and more and continued stomach heaving.  Blood work showed no diabetes, or cancer of major organs.  She is drinking well but not eating at this point. I was given pain medication to last four days.  Today is day one.  More alert today after meds, and starting to eat small amounts, and continues to drink.  Concern is stomach heaving.  Vet thinks this could be a tumor.  Somehow this doesn't sound right.  Such obvious symptoms should be clear.  On the fourth day, if there is no relief of symptoms, vet wants to put Dakota down, if she hasen't already passed away.  This is a much loved and well cared for dog.  If you have any ideas, they would be welcome.  Many thanks  cheryl

Answer
Older dogs can develop fast growing tumors.  I paid $1200 to have one removed form a 12 year old Lab.  We enjoyed another 3 years before giving up when the next one came.  

Has the vet done X_rays?  I am surprised on how much you can see of soft tissues on an X-Ray.  It almost seems he is giving up too easily on a 10 year old.  As a large breed, she doesn't have many more years.  I hate to see you give up, but also hate to send you elsewhere and spend a bunch of money to be told the same thing.