Hello everyone. I rescued a mastiff about 5 months ago. I stumbled across this forum looking for healthy ways to get him to gain weight. Jeager will be 2 years old in December. He had a severe skin infection when I picked him up and was very under weight. Skin infection is gone and coat came back. He weighed 137 pounds and the vet said he needed to gain around 15 pounds. He gained some and then lost it again. I free feed him and he won't seem to gain any weight. I am now feeding 4health large breed grain free from Tractor Supply. He is happy and has plenty of energy. You can see all his ribs and back bone. Does anyone have any suggestions.