It takes “students of dogs” years to learn the mechanics of how dogs work, and why a sound dog can work and play all day long, while an unsound one poops out after an hour. We can’t teach canine structure and how it impacts soundness and movement through brief Facebook posts, but it’s our hope that by offering snippets, we encourage you to investigate further. By now, it’s a National Purebred Dog Day^® mantra that “soundness is not just for show dogs.” If your dog plays, runs, or jumps on and off a couch, this stuff matters. If you come to learn that your dog is unsound, it doesn’t mean you love him or her any less. It means you exhibit sensitivity to your dog’s physical limits. Your dog sure won’t tell you. It is the nature of these wonderful creatures to put aside their own discomfort to be with the people they love. So, all that said, and for the moment, let’s talk about herring guts, or “herring gutted.”

In a nutshell, herring gutted refers to flat ribs that don’t have enough spring from the spine. Put another way, dogs that are shallow chested are herring gutted.

To put it in even simpler terms (usually what we need), let’s use a drawing. If “herring guts” could be explained with a simple line drawing of a heart, ribs that have enough “spring” would be the heart at the left. “Flat ribs” would be the heart at the right. Substitute the heart shape for a rib cage, and you can see the difference.

Why does it matter? It matters if you want to fit a pair of lungs and a heart into one of those heart shapes. The narrow heart shape at the right has a narrower rib cage. It reduces the effectiveness of the diaphragm muscle, and that reduces lung capacity. With less lung capacity, the dog has less stamina, and s/he won’t last as long fetching frisbees or jogging with you in the park.

For anyone who longs for a more technical explanation, a herring gut is an upswing of the breast bone that’s too close to the elbows. It’s NOT the same thing as a tuck up. Dogs can be “tucked up” and not be herring gutted if the upswing doesn’t start before the heart.

There are many fine primers on all this, and our latest favorite is Claudia Waller Orlandi’s “Practical Canine Anatomy & Movement.” You can find this workbook here.