Two Alaskan veterinarian doctors gave a lecture last week about the science behind endurance dog mushing at the Geophysical Institute's Science for Alaska Lecture.

Margaret Eastman and Denali Lovely, doctors from the North Pole Veterinary Hospital, presented the lecture "Sled Dog Science" to an audience of 445 people at the Westmark Hotel.

Experienced racing vets Eastman and Lovely have worked for races throughout the Lower 48 and Alaska, including the Yukon Quest and the Iditarod.

Their lecture discussed the evolution of the Alaskan Husky, race nutrition, common race ailments and the physiology of canine endurance athletes. The Alaskan racing husky is a mix of several dog breeds.

About 40 years ago, mushers began integrating other breeds into the husky line to bring out traits such as endurance, speed and trainability.

As a result, the Alaskan husky has evolved from the original freight dog of the mid 1900's, becoming smaller and more compact, transitioning from a bulky work animal to a slender endurance athlete.

But not all of the new characteristics are superior to the old ones. The new animals have developed thinner coats and more sensitive feet due to cross breeding.

"Racing dogs now are also more high maintenance and require a much higher calorie intake," Eastman said. "During the course of a long distance race, sled dogs consume 10,000 calories a day, which is equivalent to 18 Big Mac hamburgers."

Generating the energy to cover 100 miles a day makes nutrition an important aspect of race strategy. Depending on the weather conditions a dog's racing diet can consist of anywhere between 60 to 80 percent fat.

The high calorie density of fat delivers the most energy per volume. Most of the energy during these races comes from a high fat and protein diet. The dogs also consume five liters of water during a race day. The limited volume of a canine athlete's stomach requires mushers to carefully balance nutrition and hydration. The lecture also covered typical ailments of canine athletes.

"The problems that these dogs develop are very similar to what human endurance athletes experience during rigorous training and competition," Eastman said.

Hypothyroidism, heart murmurs and gastric ulcers are among some of the common side effects of long distance races.

But these conditions may be a physiological result of the transformation of the Alaskan Husky. Studies on hypothyroidism show that the lower hormone levels seen in canine athletes are similar to that of the greyhound, a likely result of interbreeding and the evolution of a leaner endurance animal.

Heart murmers are the result of an enlarged right ventricle, a typical condition in human endurance athletes known as Athletic Heart Syndrome.

The condition is completely reversed four to six weeks after training and shows the husky's physiological ability to adapt to intense endurance training.

Eastman said gastric ulcers are an unfortunate side effect of endurance training and a problem shared by human marathon runners.

"Any time you have exceptional performance with humans or animals there is a price to be paid. And it is our responsibility to continue doing research to solve the problems these dogs may have," Eastman said. "Overall, we hoped to communicate that these dogs can do this. They were built to compete in long endurance races."

The lecture was one of a six-part lecture series sponsored by the Geophysical Institute and the University of Alaska. Started as a way to communicate science to the public the series is organized by the public information and education outreach office at the GI.

For the past 15 years, the Science for Alaska lecture series has educated Fairbanks residents and has grown in popularity. Also presented in Anchorage, Seward and Juneau, the Science for Alaska Lecture Series educated nearly 5,000 people statewide in 2006, according to the university.