[Mikey T]

No doubt, he is a very active dog, but seems underweight. I can feel his ribs if I rub his belly and also feel his spine very easily.

All signs he is not overweight not signs he is underweight. The average basset you see is overweight to obese so it clouds peoples judgements on what the ideal weight is see the following

Corpulent Canines?

I have assessed the weight on hundreds of dogs of a variety of breeds over the past year at seminars all over the country and a conservative estimate is that about 50% of the dogs that I see are overweight; approximately 25% are actually obese. These are not couch potato dogs. These are dogs whose owners expect them to jump in obedience, to run over rough ground in retrieving tests, and to perform in agility.

1. People don't know how to determine the correct weight for their dogs. Dogs vary in height, bone structure, and muscularity, so there is no one correct weight for a dog of any given breed. The best way to determine whether a dog is overweight is to test 3 different parts of the body: the neck, the ribs, and the hips.<LI type=a>To check the neck, press your thumb and index finger deep into the side of the neck just ahead of the shoulder, and pinch them together. If your fingers are more than 1/2" apart, the dog is overweight. (Note: this is where old dogs tend to carry most of their excess fat, and they may actually be thin in other locations.) <LI type=a>To check the ribs, stand with your dog beside you, facing his butt. Place your thumb on the middle of his spine half way down the back and spread your fingers out over his last few ribs. Then run your fingers up and down along his skin. You should be able to feel the bumps of his ribs without pressing in.
2. To check the hips, run your hand over your dog's croup. You should be able to feel the bumps of his two pelvic bones without pressing down.

1. Some of you may be reading this and thinking, "I would never want my dog to be that skinny!" Think about the Olympic athletes. If you want your dog to be an athlete then it is only fair that you do what you can to help him achieve the body that he will need to perform and stay healthy and injury free for many years.

Dog Diet Do's and Don’t's

According to Dr. Tony Buffington, Professor of Clinical Nutrition, Ohio State University College of Veterinary Medicine, your puppy can be fed a regimen of specific caloric intake compared to his body condition score (BCS), using a simple one to five scale, from overly thin to obese. Using manufacturer feeding recommendations as an initial starting point, feed your puppy to a score of two and maintain this weight until he's fully grown.
... 2 Thin
- Ribs easily palpated and may be visible with no palpable fat. Tops of lumbar vertebrae visible. Pelvic bones less prominent. Obvious waist and abdominal tuck.

you should be able to see the tops of the dogs spine not just easily feel it.


Purina Body Condition Chart


even with all this information owners are still very bad a judging their own dogs body condition thinking the are thinner than they really are
Nestlé Purina study confirms link between body fat, certain health conditions

Other Purina research found that most owners couldn't accurately assess their dogs' body conditions. When owner and expert scores were compared, only 28 percent of owners characterized their pets as above ideal body condition, while 79 percent of the experts scored those same animals to be above ideal body condition. Dr. Larson says this gap is serious because pet owners are not likely to recognize that their pets are overweight and even moderate excess body fat can lead to problems.

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The odd are that you passet is not underweight but if you are still concerned after reading the above links get second opinion from your vet on the dogs body condition before embarking on a weight gain. When trying to put on weight on a dog there are two very important factor. First you want the dog to gain muscle mass not simply body fat this takes time, exercise and protein. You als need to increase the caloric content and digestability of food feed and this comes down to fat. Feeding a High protein, high fat caloric dense 9per volume diet) this is most easily found in diets disigned or designated hi-enery, or perfromance loog for a minimium of 30 percent protein and 20 percent fat. Als ome of the no grain diets meat these requairement but many if not most don't especial on the fat content. And remember weight gain should be a slow process if not all you are adding is excess body fat which is not health. The recommendation is to feed the dog at the level to maintain the body weight you want.