There was a logical reason for this in the early batches (I forget why). Pretty Bird is making their food even better (if thats' possible). They are working on new things, and one of the changes I was told that they were considering was lowering that ash content. Making a food that is so close to what an obligate carnivore eats is very difficult. That is what they are perfecting. I'm very excited about this food. If you go to their site, they have their own documents available to the public. Many documents are there for you to examine. You can see the sources of ingrediants, where they get their amino acids, what they have witnessed, etc.. This food should be a great option for GI compromised ferrets, for preventing insolinoma, and most of all to get the muscle mass that may be lacking in our american kibble fed animals. If you have tried Pretty Bird food and were unsatisifed due to the difference in odor of the food, the consistency of the feces of your animal, or because your animal wasn't crazy about the food itself ... but want so much for your animal to have a high grade food like this, don't worry. They are constantly working on other new foods with different ingredients and differnet ratio's of current ingredients to resolve so many of these issues. :D I currently have a test batch of one of their options that they are trying and it's been wonderful. I was happy with the option of another kind of ferret food on the market, but I"m excited as can be that they are always working to improve what they've already accomplished. Wolfy [Posted in FML issue 4429]