You mentioned skin allergies, and I will tell you that one of my pugs had terrible allergies on her paws (we thought from grass) and lots of ear infections. After doing a bit of reading and chatting with other pet owners I decided to try them on a grain free diet and now feed them only Wild or similar brands with NO grain, there are NO problems now, and they have been on this diet which they both love for about a year. It has also helped with weight control since pugs tend to be PIGS and we now feed only that food and some of the pellets if they are due a treat.
Pat