As a practitioner of a spiritual path it is very important to not kill an animal, also to gain food. But if you did come across a already dead animal in the forest, technically you could eat this meat since there is no life in it.
And also we must think about if we going to visit somewhere, and they serve food, that if one choose to eat the meat, that the animal was not killed dedicated to you directly. Because this would create karma not only for the one who did the killing, but also morally for you since you choose to eat it.
I used to believe all Buddhists were vegetarian. I was the guest for the day with one of Tibetan Buddhism's highest lamas. I had the honor of being invited by him to have dinner with him and his entourage of high-profile monks at a private home, where a local Tibetan chef came in to prepare for them. It took several hours as he prepared the home-made dough for the dumplings in the dish he was preparing. Meanwhile I hung out with the monks down at the lake, walked around, played the piano for a bit while his Eminence walked around with the monks.
Anyway, not being a Buddhist myself, though I certainly do draw from and understand its teachings and practice and incorporate its teaching for myself in many areas, I was surprised as dinner came it had meat in it. Oh yes, Tibetan Buddhists do eat meat. I later heard the Dalai Lama muse, "I'm a Buddhist, not a vegetarian".
Here's my personal thoughts, at this time as they are always developing. The deeper I go into my spiritual nature, my true nature, the more connectedness I feel with everything, at a conscious level. Everything is living. Everything is Life itself in form. All of us are. Every animal. Every plant. Every atom of every molecule, vibrates with that Single Life. In the deeper moments I connect with this Expression and it all becomes an extension of my own body, which is an extension of Life itself.
It gets a little deep here. I'll try to share, mostly just as an exercise for myself to see if I can. In this form, as this man on this computer who lives his life as "me" in this world, I am a participant in this unimaginably complex system of manifest forms of that Divine Reality, on this side of my face. The other side of this face sees the Infinite in everything. This side of my face sees the world and its living, organic, breathing and pulsating forms, of which I incarnate one, as do you.
The system of this universe consumes and gives rise to new forms, over and over in a continuous cycle. It is the Lungs of Life; this pulsating cycle of birth and death and rebirth, exhaling and inhaling. As a creature of this world who grew to consume food in a species which evolved to become omnivores for survival reasons, meat is included in that menu of food choices. It is not immoral to be human, anymore than it is for a cat to be a cat and eat what cats eat as the system of nature selected that for her.
But as a more higher consciously awakened being than a cat (ostensibly), I have different choices I can make as that omnivore which nature made me to me. To me, the question isn't about killing another animal, taking its life for your consumption, just as you kill a plant to eat it. It's about respecting a particular life form at its current evolutionary stage. No matter what we eat on this earth, it is all part of that system for its own continuation it designed to be as is. Each form we consume, is an incarnation of, That which is All That Is. Emptiness in form.
The other part that is a factor in the choice to eat animal products are not is more an ethical question. Since all food we consume should be eaten with reverence for its gift of itself to us, the industrialization of animals for mass consumption is unsettling as a steward of this world in our uses of it. The glorification of it as a product that must be consumed in large quantities is irresponsible and disrespectful to animal life, which is a more to be revered form of higher life. It dishonors life, that we consume out of greed.
I do eat meat. I don't consider it immoral, but I consider mass consumption of animal products to be an unaware, unconnected, or rather disconnected consciousness. As we Awaken, we see and hold life in a different more reverational way, which can see into the eyes of an animal, and know that Life in them as well as our own on the evolutionary tree.
Life has its cycles, and I too in this body provide food of myself for Life as well, as it consumes other life forms for its own being. But I try to eat such products in small moderation, such as was the dish which included it in the meal served to myself and the monks at that beautiful, sereen lake home I had the honor of being their guest at.