A hardworking dog's energy needs can double or as much as quadruple over the course of the hunting season, compared to its resting energy needs in the off-season.

That means you must feed accordingly to keep him healthy and in optimal hunting condition.

With any hardworking dog, providing a performance food containing 30 percent protein/20 percent fat vs. a maintenance formula containing 24-26 percent protein/12-16 percent fat has been shown to help them function at their best.

A performance food provides two major benefits. First, it is more calorie dense, which is important when more food is needed to meet the dog's higher energy demand of increased activity and cooler temperatures. Second, a performance formula appropriately provides a greater proportion of nutrients delivered from fats and protein to significantly increase a working dog's metabolism that favors exercise.

The question often comes up, "how do I know how much more or less to feed, and how do I best adjust the amount?" There are two rules of thumb to have in mind.

First, always feed an amount to maintain a stable body weight and ideal body condition. Second, always add or subtract in small incremental changes, such as one-fourth or one-half cup amounts every few days as appropriate to promote a stable body condition.

Use actual measuring cups to get an accurate measurement of those incremental amounts, as well as how much you're feeding.

If your dog consumes two cups of kibble a day during the lazy summer, you may have noticed that you have to increase the amount of food during the hunting season to four, or even up to eight cups a day by the middle or end of the season just to keep the dog's weight stable.

However, this significant increase in caloric need does not occur overnight and will vary for each dog. This is a gradual shift that occurs over several weeks as the season progresses, time in the field increases, and physical conditioning improves.

Hunting dogs are nothing less than elite athletes in every way. We expect high performance when they are afield and we train them for success, so it is important to provide the best nutrition.

Brian Zanghi is a research scientist for Nestle Purina Petcare.