They calculated, for example, that a medium-sized dog would consume 90 grams of meat and 156 grams of cereals daily in its recommended 300-gram portion of dried dog food. At its pre-dried weight, that equates to 450 grams of fresh meat and 260 grams of cereal. That means that over the course of a year, Fido wolfs down about 164 kilograms of meat and 95 kilograms of cereals.

It takes 43.3 square metres of land to generate 1 kilogram of chicken per year – far more for beef and lamb – and 13.4 square metres to generate a kilogram of cereals. So that gives him a footprint of 0.84 hectares. For a big dog such as a German shepherd, the figure is 1.1 hectares.

Meanwhile, an SUV – the Vales used a 4.6-litre Toyota Land Cruiser in their comparison – driven a modest 10,000 kilometres a year, uses 55.1 gigajoules, which includes the energy required both to fuel and to build it. One hectare of land can produce approximately 135 gigajoules of energy per year, so the Land Cruiser’s eco-footprint is about 0.41 hectares – less than half that of a medium-sized dog.

I have an iguana (who is vegetarian) so from the point of view of her food her environmental impact is pretty minimal. But just the other day I was doing some back-of-the-envelope calculations that suggested she’s responsible for a quarter to a third of our household electricity consumption, because of the heat lamps that have to be on day and night for her. I’d imagine she’s still not as bad for the environment as an SUV — or a dog — but once she passes away I won’t be getting another reptile.

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2. Vegetarian cats, part II

So it’s possible that your cat could become a vegetarian, but here are some good reasons why you might want to think about doing that. (And although cats live a long time, you might want to consider a less carni-centric companion animal next time). This article’s from the New York Times.

Cat Got Your Fish?

By PAUL GREENBERG
Published: March 21, 2009

My cat Coco died recently. Actually we euthanized him to alleviate his suffering from cancer. And while this was a sad moment, it was made less sad because Coco’s death also alleviated ever so slightly the suffering of the sea.

Coco, like most American cats, ate fish. And a great deal of them — more in a year than the average African human, according to Jason Clay at the World Wildlife Fund. And unlike the chicken or beef Coco also gobbled up, all those fish were wild animals, scooped out of the sea and flown thousands of carbon-belching miles to reach his little blue bowl.

The use of wild fish in animal feed is a serious problem for the world’s food systems. Around a third of all wild fish caught are “reduced” into fish meal and fish oil. And yet most of the outrage about this is focused not on land-based animals like Coco but on other fish — namely farm-raised fish.

This is understandable. Ever since the Stanford economist Rosamond Naylor concluded in a 2000 paper in the journal Nature that it took three pounds of wild fish to provide enough food to grow one pound of farmed salmon, environmentalists have been apoplectic. They argue that the removal of wild “forage” fish threatens to starve whales, seals and other predators; that anchovies, mackerel and other “pelagic forage fish” should be used to feed humans; and that feed made from wild fish can give farm-raised fish higher levels of contaminants. As a result of all these issues, ocean preservationists have focused their ire on salmon farming. But in doing so they diverted attention from another problem of equal importance: the role played by those land-based creatures that also put their muzzles in the fish meal trough.

The pet food industry now uses about 10 percent of the global supply of forage fish. The swine industry consumes 24 percent of fish meal and oil — fish oil being considered the best way to wean piglets. Poultry meanwhile takes as much as 22 percent, which means that even when Coco ate chicken, indirectly he was still eating fish. (It’s worth pointing out, too, that the PCBs that concentrate in farmed salmon similarly concentrate in pigs and chickens. A PCB is the same persistent carcinogen no matter what form of flesh delivers it to the human digestive tract.)

Meanwhile, the aquaculture industry has taken the criticisms levied against it seriously. Through a combination of selective breeding of more efficient animals, the use of fish meal substitutes from soy, and greater efforts to retrieve uneaten pellets of fish meal at fish farms, the ratio of pounds of wild fish required for a pound of farmed salmon has dropped considerably since 2004. Yes, the overall number of salmon being farmed and the subsequent demand for wild fish meal from salmon farmers are rising, but they are clearly striving toward some kind of smaller footprint at least on an impact-per-animal basis.

I am not advocating the salmon industry be given a free pass. It still has work to do, particularly with limiting the escape of those efficient, selectively bred farmed fish into the wild. But salmon naturally eat other fish, while terrestrial livestock and pets eat them because humans have deemed it commercially expedient.

If we are serious about curtailing our impact on the oceans, we should insist that land-based farm animals stick to land-grown feed. Some moves in this direction have already taken place. The United States’ national organics standards now require producers to keep fish meal use to a minimum.

But limiting terrestrial use of fish meal in our country is not enough. Fish meal and oil are now a booming international commodity. The rising demand, particularly from Asia, is fueling a perilous trend to “reduce” bigger and more valuable wild fish into pig, chicken and fish feed.

If we are to stop this devastating practice, we must step up our research to find alternatives. Indeed, the Obama administration, in search of “shovel ready” projects for the forthcoming stimulus package, would be well advised to consider programs like the National Oceanic and Atmospheric Administration’s research initiative to develop fish meal and oil substitutes from algae, agricultural byproducts and other nonfish sources. No doubt the swine and poultry industries will claim that fish substitutes are too far off and that cutting out fish meal and fish oil is not economically feasible. But similar arguments were once made by the agricultural interests that relied on whales for fertilizer.

As for pets like Coco, alternatives already exist. Several companies now make vegan cat food, though owners of vegan cats find they must supplement their pets’ diets with Vitamin A, Vitamin B12, niacin and other nutrients. But those who feel a vegan cat goes against nature (so says the A.S.P.C.A.) might rethink a pet’s potential footprint before acquiring one.

A carnivore, be it a cat, a dog or a salmon, is a heavy burden for the environment and should not be brought under human care lightly. In my family, this has become a topic of debate as we consider our next animal. Coco was an interesting and unique creature, and I argue that he cannot be replaced. To me, a vegetarian substitute is seeming more and more appealing. Lately, I’ve had my eye on a guinea pig.

Paul Greenberg is the author of a forthcoming book on the future of fish.

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1. Vegetarian cats, part I
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If you’ve become a vegetarian you might feel uneasy about keeping a cat and feeding it on dead animals. Cats require essential amino acids, fatty acids, and vitamins that are hard, if not impossible, to obtain from a vegetarian diet. But there are now cat foods specially formulated with vegetarian ingredients, as this Scientific American article points out.

Unlike dogs and other omnivores, cats are true (so-called “obligate”) carnivores: They meet their nutritional needs by consuming other animals and have a higher protein requirement than many other mammals. Cats get certain key nutrients from meat—including taurine, arachidonic acid, vitamin A and vitamin B12—that can’t be sufficiently obtained from plant-based foods. Without a steady supply of these nutrients, cats can suffer from liver and heart problems, not to mention skin irritation and hearing loss.

As such, a cat’s ideal diet is made up mainly of protein and fats derived from small prey such as rodents, birds and small reptiles and amphibians. Some cats munch on grass or other plants, but most biologists agree that such roughage serves only as a digestive aid and provides limited if any nutritional value.

Of course, providing your domestic cat with a steady stream of its preferred prey is hardly convenient or humane—and cats can wreak havoc on local wildlife populations if left to forage on their own. So we fill them up on dry “kibble,” which combines animal products with vegetable-based starches, and meat-based canned “wet” foods, many containing parts of animals cats would likely never encounter, much less hunt and kill, in a purely natural situation. Most cats adapt to such diets, but it is far from ideal nutritionally.

Veterinarian Marla McGeorge, a cat specialist at Portland, Oregon’s Best Friends Veterinary Medical Center, argues that the problem with forcing your cat to be vegetarian or vegan is that such diets fail to provide the amino acids needed for proper feline health and are too high in carbohydrates that felines have not evolved to be able to process. As to those powder-based supplements intended to bridge the nutritional gap, McGeorge says that such formulations may not be as easily absorbed by cats’ bodies as the real thing.

Some would vehemently disagree. Evolution Diet, makers of completely vegetarian foods for cats, dogs and ferrets, says that its meatless offerings, on the market for 15 years, are healthy and nutritious, and, if anything, have extended the lives of many a feline and canine, even reversed chronic health problems. Claiming that most mainstream pet foods contain artery-clogging animal fat, diseased tissue, steroid growth hormones and antibiotics no less harmful to pets than to humans, its website posts testimonials from loyal customers who claim happy and long-lasting pets who look forward to their meals.

And Harbingers of a New Age, which makes “Vegecat” kibble and supplements that provide cats with nutrients otherwise only found in meat, says that its products allow owners to “prepare food in your own kitchen, choosing recipes that fit your lifestyle.”

The vegetarian pet debate is a contentious one among vegetarian pet owners and veterinarians and is one not likely to go away anytime soon. The best approach may well be to give some of the non-meat supplements and/or foods a try. If your cat won’t eat them, or does not do well on them—take kitty to a veterinarian for a check-up to see—you can always go back to what you were feeding her before.

CONTACTS: Best Friends Veterinary Medical Center, www.bestfriendsdvm.com; Evolution Diet, www.petfoodshop.com; Harbingers of a New Age, www.vegepet.com.

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