Body Condition Score (BCS) is a 5-level or 9-level means of assessing whether one’s pet is too thin, too heavy or just right. Our hospital subscribes to the system using five divisions of body condition, as does Hill’s Pet Nutrition, who supplied the chart below.

Parameters measured in Body Condition Score are:
- ribs
- tail base
- abdominal tuck
- waist
As underweight, much less emaciated, pets are uncommon (Grades 1 and 3), we will focus on BCS Grades 3-5 today.
GRADE 3: IDEAL WEIGHT
When evaluating a pet’s body condition by the ribs, one applies light pressure as he rubs front to back. With that light pressure ribs should go bump-bump-bump and be readily apparent to the touch. With short-haired breeds ribs may even be visible.
Anatomically, a pet’s tail base corresponds to the underside of a person’s buttocks. A BCS of 3 allows for him to have a smooth contour, with no folds, and the bones of the pelvis easily felt under the skin.
Viewed from the side while standing, a pet with ideal body weight should have a “tuck” at the back of the abdomen.
Again comparing anatomical parts, our waist, like our pets’ waists, is immediately ahead of the wings of the ilium, the bones on which we humans carry our babies. Viewed from above, a pet of proper weight should have an indentation there.
GRADE 4: OVERWEIGHT
Entering Grade 4, additional body fat under the skin causes more pressure to be required in order to feel the ribs, although they can be felt with moderate pressure. No ribs are visible, even in short-haired dogs.
Abdominal tuck is still present, but there is considerably less demarcation between the lines of the abdomen and the transition to the back legs.
Caudal pelvic bones can still be felt, but they are deeper under layers of fat and an accentuated roundness is now present.
Overhead, there is little to no waist and a widening has occurred from the back of the abdomen to the rear legs.
GRADE 5: OBESE
At the obese stage, great pressure is required to feel the ribs.
This is where it gets embarrassing. The area around the base of the tail often has one or more folds, where fat has forced the skin into redundant layers.
Abdominal tuck? I don’t think so. Instead, there is sagging of the abdomen and flow into the rear legs.
Waist? Not a chance. At least once each month we have a pet come in with a complaint of “a growth on his back.” Just above the wing of the ilium bone in the pelvis is where we humans have “love handles.” Ditto for pets. These mysterious “growths” are actually fat deposits in that same exact spot. Like us, pets are rarely symmetrical, so they often have one “love handle” bigger than the other.
Other signs that your pet may be overweight include:
DOGS |
CATS |
often appear tired and lazy |
often appear tired and lazy |
lags behind on walks |
hesitate or refuse to jump onto furniture |
panting with little or no exertion |
can no longer groom himself, develops mats |
resist playing games, especially fetch |
resist playing games, especially fetch |
credit: Hill’s Pet Nutrition |
Dr. Brian Holub of Countryside Veterinary Hospital in Chelmsford, MA, calls BCS the fifth vital sign, and with so many obese pets in the United States, BCS is certainly a factor that needs to be evaluated on every patient visit.
Your pet’s doctor can formulate a weight-loss regimen for your pet, preferably at the upper end of Grade 3. However, if he has already achieved Grade 4 or 5, don’t despair. Any pet can lose weight.
See you Monday, Dr. Randolph.
MMBCS
Hi Doc, Found you BlogHoppin’ and glad I did!
Actually I think that fewer pets may have been fat but it was considered OK for them to be fat and to eat all manner of foods. As we learn to be healthier ourselves, of course we’re going to also want that for our health.
Good to have you back, RumpyDog! You are exactly right…we can always do better, can’t we? See you next week at the Hop!
Thanks for explaining this so well Dr. Randolph! As more pet lovers know to base goals on what is ideal (BCS 3) instead of what is common (fat!) I think that pets will continue to get healthier!
Well-put, Dr. Vet. It’s almost like “fat” has become the “new normal,” isn’t it? See you at next week’s Pet Blog Hop!