If an animal refuses to eat cheese, sausage, cottage cheese, does this mean that they are of poor quality (or unnatural)?

Alas, but it is a common misconception that "if my Barsik has sausage, it is of high quality."
Animals are just as addicted to flavorings, like humans. And they eat not what is natural, but what tastes better.

Maybe I have a special devoured cat, but he does not eat expensive fish at all (more precisely, none other than the dining room), he practically does not drink milk. He loves any cream, both country and store.

I ate vegetable cream with pleasure, but without enthusiasm.

I agree with the answer that animals may also have some preferences all -so.

Yes, that's right. If you do not take into account the special taste preferences of a pet, then you can even check the quality of the product on it. My cat (obligate predator) did not eat any store-bought sausages or dairy products. But he ate homemade milk and sour cream cheese with might and main. He also used to refuse raw meat, although it was his favorite food.

I am not an expert, but I think that partly it is. If we assume that the quality, for example, of a meat product depends on the amount of real content of pure meat in it. I have not yet seen a domestic cat or dog who refused pure meat or a piece of cheese (my dog ​​will sell his soul for them).

If this or that product is of poor quality, the lack of an expensive ingredient is replaced by cheap spices or soy supplements. Since our smaller brothers' sense of smell is hundreds of times greater than ours, I think they feel what "nasty" they are being offered.

I don’t eat fish and seafood (I just don’t like this smell and in general). Does this mean that fish and seafood are of poor quality?

Probably not. I just don't like them. The same goes for animals: what we like is not necessarily what others like