I was raised a vegetarian, and have kept at it even after a brief period where I tried to eat meat but kept finding it absolutely gross and unappetizing. Given my politics, alot of people seem to be taken aback at my vegetarianism but I think it fits very well with conservatism and libertarianism. Like my opposition to the killing of unborn children, I find the merciless slaughter of animals with little to no feeling of thanks on the part of those that eat the animal flesh to be morally disgusting. One man who has made some of the best arguments for compassion towards animals is Matthew Scully, a former speechwriter for President Bush who coined the phrase "soft bigotry of low expectations." Unlike alot of animal rights activists, he has been very eloquent in his presentation of the argument against animal cruelty.
I found an interview with him from several years ago while he was promoting his book Dominion. You can read over at National Review Online. Please read it, you'll go away smarter.