By Lauren Garrison

Meet Maggie, our 6-month-old German Short haired Pointer. She's brought much joy to our lives, but someone recently told me she's also increased our family's carbon footprint dramatically because of all the meat she eats.
As someone who makes a daily effort to limit my carbon footprint, I found that troubling.
My immediate reaction was that this was unfortunate, but there was no avoiding it. Dogs need meat, right?
Yesterday, while Googling "vegan," I came across this statement from Krissi Vandenberg, executive director of Vegan Action, on the Web site vegan.org:
"One major dilemma for vegetarians is feeding meat to our companion animals. Once we’ve decided not to support factory farming, can we justify feeding animal products to our companions? We’ve often made a moral exception for our companions based on the idea that there are no other options for our canine friends.
Many vegetarians and vegans are unaware that dogs can be healthy on a vegetarian/vegan diet.
Pet foods really are the worst of the worst, full of cancerous tissue and animal parts ‘not fit for human consumption’ (please see 'What’s Really in Pet Food'). Do we really want to be feeding this to our animals? After all, we are their guardians and want to make sure they are healthy. After all, we do have some viable options for our animals that we can be comfortable with in our kitchen.
I first tried feeding my three dogs a vegan diet by cooking the food at home based on recipes from a book. While I did not mind the extra time it took, the dogs did not really like it and they started to lose weight. I talked to some other folks with veggie dogs and decided to give the pre-made kibble a try. I did my research and decided to go with a food approved by the Association of American Feed Control Officials.
A basic goal of AAFCO is "to provide regulations, standards and enforcement policies to regulate the manufacture, distribution, and sale of animal feeds; resulting in safe, effective, and useful food."
While I do not completely agree with their practices nor am I completely convinced it is essential for a food to be complete, it gave me a sense of ease. Ultimately what it means is that the food is supplemented with vitamins and nutritionally complete by their definition.
I tried a few brands and settled on one that the dogs really like and have been very healthy on for the last three years. In fact, this is the best they have ever looked, especially the fifteen year old! They all love their daily supply of fresh organic veggies too. I haven’t completely given up the idea of making food for them again. There is a supplement called VegDog that is listed as complete and needs to be added to homemade food every day.
From talking with other folks, I realize this is still a controversial issue. I find assurance in the idea that if dogs can be just as healthy (or even healthier in many cases) not consuming animals then there really is no reason to not at least give it a try. We now have substantiated data and collective personal experiences that support a healthy, vegetarian diet for dogs. Since there are several AAFCO approved brands on the market to choose from, why not make the ethical decision to try a vegetarian diet for our companion dogs. I am confident I’m not risking my dogs’ health and feel great to not have to go buy that bag of lamb and rice dog food every month."

Another interesting article on slate.com exploring the environmental impact of pet food ran today. It provides a few different viewpoints on the issue, including this:
Most commercial dog and cat food is made from the parts we humans don't eat, like organs, scraps, and rendered bones and tissues.
Looked at one way, then, pet food is a kind of recycling operation: It takes waste products and finds a use for them. From an economic perspective, these less-than-palatable parts aren't that big of a deal.
Clark Williams-Derry, blogging for the Seattle-based think tank Sightline Institute, notes that byproducts account for at most 15 percent of a livestock animal's value. Thus, he argues, the pet food industry contributes relatively little to the total environmental impact of a meat-producing cow, chicken, or pig. We grow and slaughter those animals to feed our yen for meat—not to make the scraps that go into pet food. So 100 calories of byproduct meat should be credited with a lower impact than 100 calories of human-grade meat.

What do you think? I would never want to put Maggie's health at risk, and would have to do much more research before considering such a change in her diet. But it's interesting to see that people have done it with success.