I have a silky terrier that is 1.5 years old. My little guy is healthy and active. My vet says he is border line thin but healthy and physcally fit. She told me to keep an eye on his wieght so he doesn't lose any more. I do not want to comprise my dogs health in anyway, but everyone who holds/pets my dog comments on his protruding back bone and ribby sides. I feed him high quality food twice a day. He eats all he wants in both feedings. Personnaly, I think he is beautiful, but wonder if I need to adjust his diet in a way that puts a little bit of meat on his tiny structure so his backbone doesn't seem to evident.

Did he have a full check-up while he was at the vet? No sign of worms or gastric problems?

You can try introducing some richer foods into his diet. Chicken wings are good (raw, not cooked), they are very fatty, but start giving them slowly, just 1/3 of a wing on day one, then 2/3 the next day and so on or they could cause constipation.

Lamb flap is another good fatty meat. Again, only start in very small amounts and build up. Lamb flap is a different kind of fat, it is a healthy fat but you do have to be careful in not giving too much or it can lead to pancreatitis. Half a fist worth a day is fine added to the dry food.