Understanding body and muscle condition scoring

Photo: Андрей Журавлев/Adobe Stock

Body condition scoring for cats and dogs should be done separately from muscle condition scoring, as the two are two completely different things. So, how is a body condition score obtained for both feline and canine patients; and how should muscle condition be scored? In a lecture at the Fetch Long Beach conference December 6 to 8, 2024 in Long Beach, California, Valerie J. Parker, DVM, DACVIM (SAIM, Nutrition), offered some insight, as well as obesity and low weight prevention tips.

Body condition

Cats

The World Small Animal Veterinary Association (WSAVA) Global Nutrition Committee body condition score guidelines should be followed when determining what body condition score a feline patient has. A score of 5 out of 9 is ideal. Cats with a body condition score of 5 will be well-proportioned and have a visible waist behind their ribs from a top view. Additionally, their ribs will be palpable with slight fat covering. These patients will have minimal abdominal fat pad.^1,2

When it comes to palpating body condition in cats, Parker stressed the importance of standing the cat up and stretching them out. “Cats [are] very challenging to do a good body condition score [on] if you don't get them up and stretch them out, right?” Parker said. “You can't do a good body condition on a cat that's hunched up in its carrier on the table—they always are going to look heavier than when you stand them up and stretch them out, so sometimes body condition scoring a cat is a 2-person job.”

To correctly body condition score a feline patient, the veterinarian should begin right behind the shoulders, approximately halfway between the dorsum and the ventrum, and go back and forth over the cranial two-thirds of the rib cage using the flats of their fingers.

“With that said, when I am using the flats of my hands very gently, going back and forth over those ribs, if I make a fist and feel over [my] top knuckles, if that's what the ribs feel like, that's a 3 out of 9,” explained Parker. “If you open your hand palm down and feel over [your] same knuckles there, if that's what [the patient’s] ribs feel like, that's a 5 out of 9.”

A patient with a score of 7 out of 9 will not have a visible waist. “So, a 7 out of 9 for me is an animal that's kind of straight across from shoulders to hips,” said Parker. “Now, you can be straight across on a 7 out of 9, and you can be straight across on a 9 out of 9, and that has to do with how much back coverage there is over those ribs,” she continued.

Parker disclosed that she believes a body score of 4 out of 9 is acceptable if the patient is young and metabolically healthy. However, in patients that have a chronic inflammatory condition, such as chronic kidney disease, irritable bowel syndrome, or hyperthyroidism, it is best to guide the patient back to a body condition score of 5.

Dogs

In dogs, a body condition score of 4 out of 9 or 5 out of 9 is ideal. In a score of 4, the ribs should be easily felt and will have minimal fat covering. Additionally, the waist will be easily visible and will be able to be seen from above. There will also be a noticeable abdominal tuck. Patients with a body condition score of 5 will also have easily palpable ribs without excess fat covering. The waist will be visible behind the ribs when viewed from the top and the abdomen will appear tucked up from a side view.³ According to the WSAVA Body Condition Score sheet, scores of 1 to 3 are under ideal, and scores of 7 to 9 are over ideal.

Muscle condition

When it comes to muscle condition, Parker emphasized the importance of scoring muscle condition independently of body condition. “Far too often, I see people underscore [body condition score] because the patient is muscle wasted,” she said.

Parker also advised against using numerical scoring systems for muscle condition, as numbers can be confusing and subjective. “We’ve got different scores that have been reported or suggested over the years, and they’re completely opposite,” she explained.

WSAVA and the American Animal Hospital Association (AAHA) recommend using words for muscle condition scoring, such as ‘normal muscle mass,’ or ‘mild,’ ‘moderate,’ or ‘severe’ atrophy or loss.¹

To assess muscle mass, the veterinarian should visually examine and palpate the epaxials, hips, shoulders, temporal muscles, scapulae, vertebrae, and pelvic bones. In early muscle loss, the epaxials are often the first affected because, again, muscle mass does not correlate with body condition. “You can have a very lean dog with good muscle mass. You can have an obese animal with moderate or severe muscle loss. So just separate them out in your mind and just score them independently,” said Parker.

The impact of low weight or obesity

Having an ideal body condition score is important for several reasons. Adipose tissue, or body fat, can act as a negative source of inflammatory cytokines. In cats, being low weight or obese can prompt skin disorders, particularly when these felines are not able to groom themselves. Moreover, having low weight or obesity can also lead to impaired respiratory function in cats and dogs.

Additionally, obesity greatly increases the risk of a cat developing diabetes mellitus, with obese cats being 4 times more likely to develop diabetes than lean optimal weight cats, according to Parker. Although being obese does not cause orthopedic disease, it can contribute to the clinical signs of the disease.¹ “There are some studies that say that being obese could even increase the risk if developing certain neoplasms,” added Parker.

A cat’s and dog’s body condition score also can an effect on their lifespan. In her lecture, Parker shared 2 studies that investigated the effect of body condition on the lifespan of canines and felines.

The effect on dogs

The first study followed 48 Labrador Retrievers from 7 litters from birth to death. Participants were assigned to one of two groups. The first group was fed ad libitum (free fed); this was later changed to a controlled feeding amount. The second group was fed 25% less.

The study found that dogs kept leaner, with a body condition score of about 5 out of 9, lived a median of 2 years longer than those kept at a body condition score of 7 out of 9. This was attributed to the leaner dogs being more comfortable, especially in terms of mobility, and experiencing less severe osteoarthritis. Although dogs in both groups developed the condition, the second group required medical management for osteoarthritis for a shorter period of time.⁴

The effect on cats

The second study that Parker shared looked at cats and found that being underweight was linked to a shorter lifespan, while cats with a body condition score of 9 out of 9 also had shorter survival compared to those with a body condition score of 5.¹

“You're going to find this in a lot of studies where cats have this, what's called a “U-shaped survival curve.” So being really light or really heavy is associated with a worse survival than somewhere in the middle, and this study would support that,” explained Parker.

Prevention

For Parker, prevention is key. She emphasized that prevention is more effective than managing low weight or obesity once it has developed. As Parker explained, prevention begins at the first healthy puppy or kitten exams and in talking to owners about healthy body weights and healthy body condition scores. Body weight, body condition score, muscle condition score, and diet history should be addressed in every visit, every time. “And it doesn't have to be a very in-depth diet history if the dog or cat is healthy and doing well. But anytime you get a red flag, it's under conditioned, it’s over conditioned. Red flag, they're on an unbalanced diet, that then requires more detail and more diving in and finding out what's going on,” said Parker.

She also suggested teaching clients how to do a body condition score on their pets. For professionals seeking a free resource, Parker recommended the AAHA Nutritional Assessment Guidelines for Dogs and Cats.

References

1. Parker VJ. Obesity Prevention and Management. Presented at: Fetch dvm360 Conference; Long Beach, CA. December 6-8, 2024.
2. Body Condition Score. World Small Animal Veterinary Association. August 13, 2020. Accessed December 10, 2024. https://wsava.org/wp-content/uploads/2020/08/Body-Condition-Score-cat-updated-August-2020.pdf
3. Body Condition Score. World Small Animal Veterinary Association. Accessed December 10, 2024. https://wsava.org/wp-content/uploads/2020/01/Body-Condition-Score-Dog.pdf
4. Kealy RD, Lawler DF, Ballam JM, et al. Effects of diet restriction on life span and age-related changes in dogs. Journal of the American Veterinary Medical Association. 2002;220(9):1315-1320. doi:10.2460/javma.2002.220.1315.
5. AAHA Nutritional Assessment Guidelines for Dogs and Cats. American Animal Hospital Association. Accessed December 10, 2024. https://www.aaha.org/wp-content/uploads/globalassets/02-guidelines/weight-management/nutritionalassessmentguidelines.pdf