In the Tibetan Buddhist tradition, one of the most basic prayers is that all sentient beings achieve enlightenment - sentient beings connoting anything that has a face or demonstrates an aliveness in any way, shape or form. (Let's hear it for the plant kingdom too.)
Although enlightenment is a spiritual goal that is mentioned frequently in sacred texts and in the vernacular, I have no idea what that means. We can talk about enlightened activity, and in that sense one could postulate that it means compassion, love, wisdom, good acts, and so on. But according to the great teachers of the ages, the last obstacle to enlightenment is the desire to become enlightened - possibly because that desire implies an emphasis on the 'self,' which is always a sticking point if one wants to claim that his or her motivation is selfless or unconditional.
Lest this discussion turn into an exercise in theological masterbation, I will cut to the chase. Apparently, mice, as well as chimps, pigs, elephants, humans, etc. demonstrate empathy towards others in distress, usually members of their own species - although You Tube provides us with numerous examples of interspecies loving-kindness. (My favorite is the hundred year old tortoise who adopted a baby hippo after a tsunami of historic proportions swept them downriver, away from their usual hangouts.)
I have never eaten a mouse for dinner, but certainly cows, pigs, fish, chickens and many a plant have found their way into my cooking pot. Now that I know that virtually every sentient being demonstrates empathy, the logical conclusion is that a bevy of other noble qualities inhabit their brains as well.
Really, do we want to eat someone or something that cares about their fellow beings and possibly even us? (Cultures who eat dogs, beware of an especially negative karma.) My recent aversion to chowing down animal flesh/fish, accompanied by a kinder, gentler attitude towards grains and vegetables, now makes sense. Some subconscious mysterious message filtering into my conscious brain informs me that one should not eat their own.
At the very least, if we continue to eat our friends that share Mother Earth with us, it behooves us to say a prayer of thanks for their sacrifice in giving up their lives so that we may eat and live. If this sounds close to a certain world famous historical figure of Biblical proportions, it is, in truth, a similar sentiment.
Thank you, all beings, for your contribution to the interdependent world in which we live.