A very funny aspect of our domestic cats is related to the time of feeding. Many cats, in fact, often meow nonstop in front of the bowl, even though it is still half-full.
The cat has always been considered a very smart animal, due to some typical attitudes. Among these, we find above all its ability to ask continuously for food, even if the bowl is not empty yet. It would seem that, according to feline logic, there is no middle ground between a full bowl and an empty one. The view of the bottom of the bowl automatically indicates that the food is finished, and our task is to fill it. Immediately.
Partially, this reasoning is true, but some aspects should be clarified.
The cat is an animal that is very used to its routines and habits, so if it begins to understand that by meowing it will get food, it will do so very often. By doing this, the bowl will be constantly regenerated with new and fresh crunchies each time. We know very well, in fact, that he is able to evaluate the freshness of the food we offer him, so crunchies left in the bowl for several hours may no longer be interesting for him. If your cat belongs to this category of superfine palates, it will also tend to meow in front of a bowl full of food.
On the contrary, if the cat is desperate only at the sight of the bottom of the bowl, it will probably be enough for you to move it a bit, redistributing the treats inside. Et voila, the bowl is full again just by moving them around a bit. In these cases, the explanation could be more complex.
In nature, felines tend to prevent all aspects that can lead to deprivation. This means that if the bowl is half-empty, they receive some kind of alarm signal, which warns them of the impending fasting period. In this case, therefore, they meow to warn us that the food is about to end, so it would be preferable to fill it immediately, rather than risk finding it empty at the next peckish.
That is not all. In fact, some cats are "social eaters", which does not mean that they tend to tear their friends to pieces, but they refuse to eat if they don’t have company. The typical situation is the cat who wants to be stroked while eating or just requires our presence. This will calm him down, allowing him to eat quietly.
So don't worry if your cats gets desperate in front of the half-full bowl. He sees the food, but he is just a little demanding.
picture explanation: piena = full vuota= empty
Source : http://fluffsofluv.com/when-your-cat-is-hungrybut-has-plenty-of-food-left/