Imagine being responsible for designing menus for all the animals at a zoo – from mammals weighing several tons to the tiniest of insects. On top of that, imagine putting together a nutritious diet for each and every one of them.
At the Cincinnati Zoo & Botanical Gardens, that person is Barbara Henry, curator of nutrition. Like many of the species she studies, Henry is a bit of a rarity. Only 20 out of 200 accredited Association of Zoos and Aquariums (AZA) zoos in the country employ full-time nutritionists. As part of a team effort, she works directly with veterinarians and keepers to create healthy, appetizing meal choices to delight the zoo’s vast variety of residents.
“My position is really cool and fascinating because it’s like a puzzle, and every day you have pieces to a puzzle and you have to see which pieces fit where,” Henry said. “And even if on paper you have the best diet in the world, that doesn’t mean the animal’s going to eat it.”
Just as in a fine restaurant, a variety of fresh meat and produce is delivered throughout the week to the zoo’s commissary. In addition, Henry said, they purchase local fare including an array of live worms, fish and crickets as well as fresh cattle blood for the vampire bats. She said annually the zoo spends about $1.1 million for food and bedding (such as hay and straw) alone. Henry noted that all foods served to the animals is of the highest quality and must meet strict USDA guidelines. She said even the meat the zoo feeds the carnivores is fortified with nutrients.
“We get human quality,” she said. “I want it to be fresh. I want the produce to be free of mold or slime. I wouldn’t feed anything to an animal I wouldn’t eat.”
To design a diet, Henry said she begins with the basics by examining what that animal eats while foraging in the wild. She said she then looks at a number of factors such as age, hormones, reproductive cycles and the dynamics of whether such animals eat in a group or alone. She said some species that have been studied extensively already have nutrition guidelines in place. For those that don’t, she said, she looks at nutrition guidelines published by the National Research Council for the closest domestic animal to that particular species.
“We consider those nutrient requirement books our bibles, because then we can try to extrapolate that information out,” she said. “We use information for cats and dog, primates, cattle, horses, laboratory animals, swine, sheep, fish – because those domestic animals have been studied extensively to the very minute nutrient and quantity of that nutrient.”
Besides studying domestic animal nutrition, Henry explained, examining human nutrition is becoming increasingly important in terms of animals. Besides the biological similarity between humans and primates, she said, many animals in zoos are developing diseases associated with old age like arthritis or diabetes.
“If you think about it, animals in the wild don’t live nearly as long as animals in captivity,” she said. ”So animals in captivity living longer are going to come up with some diseases that are maybe studied more with humans, so you can maybe extrapolate that information over.”
Diagnosing an animal’s eating habits can be like solving a mystery, Henry said. In addition to food being nutritious, she noted, it must also appeal to the animal’s sometimes capricious nature. To make food more exciting, she said that keepers must constantly rotate choices, as well as come up with ideas of how to make mealtime fun.
In the Africa exhibit, for example, she recently introduced carcass feeding for the painted dogs . She said offering the pack a goat carcass simulates their experience in the wild. The feeding has been so positive, she said, they next plan to begin carcass feeding with lions. But she said the ritual isn’t suited for all the carnivores in the zoo. Besides the fact that many can’t digest fur or bones, she said, a number of animals simply wouldn’t know what to do with the carcass.
“You have to understand, almost every single animal in this zoo, not all, but almost all, was born in captivity,” she said. “So they’re not necessarily used to that. They’ve tried (carcass feeding) in the past and the animals have been, like, what is this thing and why did you put in in my exhibit?”
In addition to her duties of ordering food and designing diets, Henry gets called on specific cases, such as helping nursery and quarantine head keeper Dawn Strasser satisfy Dale the takin's voracious appetite . Or to assist veterinarians for a variety of reasons, such as suggesting food for animals with sore gums or finding creative ways to disguise medicine in food. She said the most challenging of species are the primates, who are so intelligent it’s almost like working with a child who refuses to negotiate.
“You can’t say, ‘If you take your medication, we can go out for ice cream.’ It doesn’t work with an animal,” she said. “The primate keepers tell me they somehow know and they’ll find (the medicine) in food. They’ll put it in their mouth and they’ll mull it around and they’ll hand the pill back to the keeper. So sometimes we have to think outside the box with our ideas.”
With an undergrad degree in animal science and a master’s degree in ruminant nutrition, Henry said she was fortunate to be one of only three people to take part in a residency program for animal nutrition at the Brookfield Zoo in Chicago.
In 2002, she said, her mentor and animal nutritionist program developer Susan Crissey died of ovarian cancer, making the education Henry received even more valued. After spending 11 years honing her skills in Chicago, she said decided to take a job at the Cincinnati Zoo.
“So I’ve been here 10 years,” she said. “It’s neat to work in the environment I do and I love the zoo. I love what I do because it changes and you have such excitement, because we focus so much on conservation. There’s great information from people who have been doing conservation out there and that helps everybody where the animals are concerned.”
Here are some Cincinnati Zoo food fun facts:
In one year, the zoo spends $74,000 on meat:
41,600 lbs. of raw meat
71,531 lbs. of fish
1,196 lbs. of rabbit
In one year, the zoo spends $269,000 on produce:
That’s more than 350,000 lbs. and 27 kinds of fruits and vegetables including:
23,000 lbs. of apples
6,000 lbs. of oranges
22,500 lbs. of bananas
11,000 lbs. of grapes
12,100 lbs. of carrots
17,000 lbs. of sweet potatoes
210,010 lbs. of lettuce
The zoo uses over 8,892 average bales of hay each year. If stacked end on end, that would be 23 times as tall as Chicago’s Willis Tower (formerly Sears Tower).