Hope your dog pulls through! Best of luck!
Try a new food that I think has come out. Canidae, which also makes Filidea. My 12 yr old cat started eating Filidea and its the only food he can keep down without puking it back up. So it seems pretty gentle to his digestive system. It also has put wieght on him. He had a Theyroid problem and his metebolism sped up 4 times the rate you or I would digest a meal. It is also supposed to be all natural, even though, I have seen a few bi-priducts on there. My two dogs, ones 9 and the other is a year love canidea to. Seems to have made there coat more soft.
Also another food, I've seen on the market is a brand called Nutro. There brand is supposed to be all natural to, but I think thats kinda a misconception, only because they have senior, low fat, puppy, ect. Least with the Canidea line they only have two products: Regular or Senior, which seems like their food seems to be geared to all stages of life, which is kinda convient moneywise.
ps I am in no way some crazed advitisor here if it came off that way. Just stating what has worked for me
Best of luck again.