Nutrition and Nosework

[DogGoneGood]

Nutrition and Nosework
By Cheryl S. Smith
Dogs in Canada June 2007 issue

A limited number of studies indicate that diet can affect scenting ability. The canine nose is a wondrous thing. Statistics – such as dogs may have up to 60 square inches of olfactory mucosa compared to a human maximum of one square inch, or dogs’ odour-detecting cells in the nasal cavity can number from 125 million to 300 million while humans can claim just 5 to 10 million – sound impressive, but don’t express the sniffing feats of which dogs are capable.

We’re all familiar with search and rescue and probably the Beagle Brigade working at airports to sniff out prohibited fruits, plants and meats in luggage. But did you know that dogs are being used to find termite infestations in homes, sniff out the scat of endangered species (including whales!), and select humans suffering from various forms of cancer by smelling their breath or urine?

So what does this have to do with nutrition? A limited number of studies indicate that what you feed a dog can have an effect on how well its nose operates. Eric Altom has been interested in this area since before he received his Ph.D. in canine nutrition.

While still a graduate student at Auburn University, he became involved in a study assessing the effects of conditioning and nutrition on the performance of Pointers. Eighteen Pointers, aged two to four, were split into three groups. Six Pointers ate a diet with 12-per-cent fat, another six ate a diet with 16-per-cent highly saturated fat, and six ate a diet with 16-per-cent mostly unsaturated fat. In each group, half the dogs were exercised on a treadmill three times a week.

Once a week, researchers measured the dogs’ scenting ability, gave them an hour-long stress test on the treadmill, then measured their scenting ability again.
Conditioning – or lack thereof – showed a profound effect on scenting ability. The dogs not receiving conditioning showed a 69-per-cent decrease in post-exercise scenting ability. But the dogs fed the highly saturated- fat diet showed an even greater decrease in scenting ability, hinting that dietary fat plays a role in keeping dogs’ olfactory systems working well.

Study points to better performance
The testing was done by Larry Myers, D.V.M., director of the Institute for Biological Detection Systems at Auburn. The dogs were taught to wear a blindfold and lie quietly in a closed room, with white noise playing. Electrodes were attached and a videocamera was focused on the dog’s nose. A vial containing a known (tiny) percentage of an odour-causing substance was presented under the dog’s nose and the response recorded. Myers notes, “When we did a critical evaluation of the program, it turned out the dog’s behaviour was actually more reliable. We watch the dog sniff. Simple is frequently better.”

Though agencies have a lot of money invested in the scenting abilities of their bomb-sniffing, drug-sniffing, and search-and-rescue dogs, there has been surprisingly little interest in the connection between nosework and nutrition. The only follow-up study was also performed by Eric Altom, with Martin Coffman, D.V.M.

In this study, they used 23 English Pointers that were working bird dogs. The dogs were randomly divided into two groups, with one group fed a popular commercial “performance” diet and the other group consuming a regular diet widely used for sporting dogs. The diets arrived in plain brown wrappers with only stickers to differentiate them.

This time there was no difference in exercise. The dogs were all used for quail hunting through an entire season (November through February) in Georgia. The handlers kept records of how long each dog hunted each time out, the number of finds, number of flushes, attitude of the dog, and reason for retiring the dog for the day (fatigue, lack of interest, injury). All of the dogs completed the study.

When the results were evaluated, the dogs eating the high-fat performance diet demonstrated superior hunting ability. They found an average of 7-1/2 coveys/
singles in each hunt, compared with the other group’s 4-1/2 coveys/singles.

Their finds per hour of hunting averaged nearly 2-1/2, with the other group managing just over 1-1/2. The differences were even more notable on hot, humid days, according to the handlers’ observations. The dogs consuming the performance diet also maintained their body weight and overall condition better than the dogs on the regular diet.

Though the study numbers are limited, it would seem that for dogs being asked to use their noses in hard working conditions, a high-fat diet would be a good choice.

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The author of Pudgy Pooch, Picky Pooch: A Pet Owner’s Guide to Dog Food and Canine Nutrition, Cheryl S. Smith is an award-winning writer. She shares her life with ‘Nestle,’ a Border Collie mix who is busy earning badges with the Dog Scouts of America.