In the Critique of Pure Reason, Immanuel Kant associates consciousness with the concept of the unity of the self or with the transcendental apperception [1] of the self (sometimes incorrectly referred to as the transcendental subject).
This element is the one that provides the object of consciousness (what is observed) of a quality of unity. It is not something that is mixed with the rest of the world, but clearly bounded. The reference in your text has precisely such sense: "something that is like to be ME" implies that there is something that IS NOT ME, like another one's feelings, or the perception of a rock as non being part of the body.
So, the idea of a unity around the apperception of ME is, probably according to your text, the key factor of the notion of consciousness, which some beings are not capable of, like bacteriae.
When a sheep looks for food, it clearly targets an object (implying NOT targeting what IS NOT THE OBJECT), which does not necessarily correspond the one we would target. E.g. a sheep would normally not bite a rock or its leg when trying to eat, but will do it with grass, so, the sheep clearly discriminates the object food from what is not food.
[1] https://askaphilosopher.org/2012/11/14/explaining-kants-transcendental-unity-of-apperception/