Hi Susan, Is Natures Variety a premium dog food? If so, which is better the Instinct or Prairie?

I have feed my 7 yr. old Golden both kinds, and the Instinct seems to make her really gassy! The prairie has grains, she does not become gassy with this one, but she does have a yeast problem, she has also gained weight on this brand of food. What do you think of the Evo reduced fat in comparison to the Nature's Variety? Thnaks, Carol

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