Dr Brown was part of a team of scientists who monitored the health and performance of Siberian huskies over a 10-week sled-racing season.

They concluded that hard-working dogs can perform just as well on a meat-free diet as they do on a meat-rich diet.

Their results, published earlier this year in the British Journal of Nutrition (Vol 102, pp 1318-1323), add to the evidence that dogs fed an exclusively vegetarian diet can be just as healthy and happy as their meat-eating relatives.

Dr Brown, the canine nutritionist from the University of New England who led the husky trial, is confident that dogs can thrive on a meat-free diet.

She warns dog owners, however, that preparing an adequate vegetarian diet for a dog is more difficult and time-consuming than they might think.

Dr Brown has concerns, too, about some of the vegetarian dog foods that are becoming commercially available in growing numbers.

Many of these, she said, are untested.

“People manufacturing and buying vegetarian and vegan pet foods are often against testing, believing that even feeding trials are cruel,” she said.

“But feeding trials can be done in a friendly way. For my own trials, I borrow people’s pet dogs - some of them show dogs - and they are always well cared for. People visiting my kennels comment on how happy the dogs look. And they are.

“When I feed my own dogs, I want to know that what they’re eating is nutritionally adequate.

“As dogs belong to the order Carnivora, it’s often assumed that they are exclusively carnivorous, but in fact they are omnivores, belonging to the same superfamily within the Carnivora as the bamboo-eating giant panda and the omnivorous bear.”

In a paper presented at the University of New England during the international conference Recent Advances in Animal Nutrition 2009 and published in the conference proceedings, Dr Brown addresses the common argument that vegetarians should not impose their own values on their pets.