Elephants are another special case. I cant assess them the way I do other animals because their skin is very thick. Instead, we use a visual score that looks at the same points I would touch but matches pictures with the text descriptions. Elephants also pose an additional challenge since they are herd animals and all have access to the same hay, which is the bulk of their diet.
When our female Asian elephant, Bozie, arrived at the Zoo in 2013, she scored in the 8 to 9 range on the body condition scale. While she was in quarantine, we transitioned her off the food she received at her previous institution and onto the diet we feed our elephants. This included a change in the type of hay and pellets, and an adjustment in the proportion of fruits and vegetables. Once she fully transitioned to her new diet, our goal was to make systematic decreases to help her to lose the excess weight.
On the other end of the spectrum, we had a geriatric female Asian elephant, Ambika. She tended to be on the lean side, so we gave her a special, chopped hay with more calories to help maintain her body weight. It was great for her and she maintained appropriate body condition until her death in 2020.
Between Bozies release from quarantine and Ambikas death, they lived together in a small herd with another female. This posed a problem diet-wise. As I mentioned previously, the entire herd eats the same hay. Ultimately, the elephant team and I decided it was more important to maintain their social structure and keep Ambika at a healthy weight because she had the most limitations in the group setting.
After Ambika passed, Bozie was transitioned back to the Zoos normal hay, which has less calories. At her highest, she weighed close to 9,500 pounds (4300 kilograms). Within the last year and half, she lost all the extra weight. Her current weight is about 7,900 pounds (3600 kilograms) and she recently scored a 5 out of 9!
Read this article:
Problem-Solving Animals' Nutrition Needs: Stories from a Real-life Zoo Guardian - Smithsonian's National Zoo and Conservation Biology Institute