Here's the most recently updated More Dooks chart. Please note that the chart hasn't been updated since late 2013. The Marshalls food has had an ingredient change (removal of molasses) that may cause a slightly higher rating (esp for the Select formula) 

http://moredooks.herobo.com/search.php?chart=ferret 

Wysong has also undergone a formula change, though it's proposed to go back to the original formula.

Also note that high pea content has increasingly been correlated with bladder stones in ferrets. Zupreem Grain free and Taste of the Wild cat seem to be common culprits.



 

Ferrets: Wesley, Percy, Owen    -rip Bandit-
Bettas- Kitty, Pip, and Logan
Sun Conure- Kita
Gerbils- Piper and Tailer