Dinner at the National Zoo

It’s 6 a.m. and the sun is just starting to rise over the Smithsonian’s National Zoo and Conservation Biology Institute in Washington, D.C. The gates don’t open for another two hours, but the grounds are already abuzz with activity.

In the animal commissary, staff members ready hay, bamboo, and other plants for the elephants, pandas, and ruminants, while some meticulously prepare the special diets required of the zoo’s nearly 400 other species, which range from aquatic caecilians (a type of eel found in Colombia and Venezuela) to two-toed sloths — more than 2,200 animals in all. As some staff members cut fruits and vegetables, others retrieve dead rabbits and mice for the zoo’s hungry reptiles, or ready large chunks of meat for the big cats. It’s a bustling, four-star restaurant for the furred, finned, and feathered, and overseeing it all is Mike Maslanka, the zoo’s Senior Nutritionist and head of the Department of Nutrition Science.

One of just 25 zoo nutritionists in the entire country, Maslanka’s expertise is in high demand. Prior to joining the National Zoo in 2006, he gained invaluable experience at the Brookfield Zoo in Chicago and the Georgia Aquarium in Atlanta, among others.

Maslanka oversees a staff of 13, including clinical nutritionist Erin Kendrick, who is in charge of diet balancing and formulation. Working with the zoo’s curators, keepers, and veterinarians, Kendrick formulates the daily diets for a large percentage of the zoo’s animals, with the goal of maintaining proper weight and health.

“My main responsibility is to ensure that the ­nutritional needs of every animal in our collection are being met. Changes are always happening, and for a variety of reasons,” says Kendrick, who came from the St. Louis Zoo in 2012. “That could be formulating a diet for a species we’ve not had before, balancing diets for growth or reproduction, adjustments for body weight preferences, determining safe plants for forage, developing hand-rearing formulas, and of course managing clinical health cases. I’m also a nutrition advisor for several species and involved in research projects, outreach, and education.”

The zoo’s commissary is where the culinary magic happens. It’s a massive 23,000-square-foot facility with large freezers and a sizeable prep area, a necessity when preparing food for animals that range in size from the tiny coronated frog to an Asian elephant. Maslanka oversees ­procurement of all of the diet ingredients for the zoo and its 3,200-acre research facility in Front Royal, Virginia, about 70 miles away.

“Diet preparation is a little bit sous chef, and a little bit prep chef, but it’s basically translating the recipes that Erin provides, which are on diet cards,” Maslanka reports. “Our inventory is hundreds of ingredients and includes mealworms, crickets, fruit flies, mice, rats, rabbits, and squid, all the way through all of our produce items, which are often things you would find in your local grocery store. Then there are all the different meats, which come from USDA-inspected facilities. Our annual food budget alone is more than a million dollars.”

The zoo’s big cats and other large predators receive meat as their primary diet. Maslanka estimates that between the two facilities, his team prepares close to 150 pounds of meat per day, usually a combination of beef, horse meat, and whole prey such as rabbits, mice, and rats. Big cats have big appetites, so the meat could be as large as the shoulder or back leg of a cow. This is known as carcass feeding, and aids oral and digestive health because it takes more time, energy, and work to eat and digest compared to butchered meat. Carcass feeding also stimulates natural feeding behaviors.

The National Zoo is unique in that it grows its own hay on a 220-acre tract at its Front Royal facility, as well as its own bamboo, the latter in conjunction with more than two dozen regional landowners. “We help them manage the bamboo, which is fast-growing, so it doesn’t get out of control,” Maslanka observes.

The commissary staff are rarely involved in the actual feeding of the animals — that’s left to the animals’ keepers, who use a variety of enrichment techniques to keep the animals active and motivated. “In the dietary sense, enrichment is designing the diet, and subsequently using it, to ensure the animals we’re feeding have opportunities for species-­appropriate behaviors and choices,” Maslanka explains. “We’re making sure we meet the nutritional and behavioral needs through diet design and delivery.”

A good example of making animals work for their dinner is feeding the zoo’s new giant pandas, Bao Li and Qing Bao, who went on public display on January 24. “Bamboo is not a terribly interesting diet ingredient,” Maslanka notes. “It’s there and they eat it at their leisure. But there are other parts of their diet, such as small produce items or dietary biscuits, that we may use to condition them and help them become comfortable with us. Instead of just handing them a biscuit, we can put it in a puzzle feeder that they have to roll around in order to get to the food inside, just like your dog at home. That keeps the pandas engaged in a simple way.”

A similar enrichment approach is taken with the zoo’s six Asian elephants, which receive up to eight bales of hay each day. Rather than just dumping the hay on the ground, it’s placed in several remote hay feeders scattered around the edges of the elephants’ two-acre outdoor compound. “The feeders go off at different intervals in different locations,” Maslanka says, “so the elephants have to move around their entire enclosure to get some hay. This keeps them engaged, and also benefits them because we don’t want them to eat their diet in one sitting. That’s not good for any herbivore.”

Maslanka and his crew work closely with the zoo’s veterinary department, which includes 28 veterinarians, pathologists, technicians, and other specialists, headed by Chief Veterinarian Don Neiffer, VMD, who joined the National Zoo in 2014. “In addition to diet, Mike oversees the body scoring assessments, which is a measure of an animal’s condition, in consultation with my team,” Neiffer reports. “It’s important that we come up with a rough agreement of where an animal is in its nutritional plane, because that is going to direct a bilateral approach to helping an animal if it’s too thin or too heavy.”

The veterinary department is not involved in the creation of specific diets, though it does have a say regarding items used for training or enrichment. This is necessary, Neiffer says, because there may be a medical concern associated with the use of certain foods that the nutrition department is unaware of.

Additionally, the veterinary department will consult with Maslanka if an animal requires oral medication. “We sometimes want to use a food that isn’t necessarily good for an animal over the long term because of its caloric content, but is a good way to get a medication, such as antibiotics, into an animal,” Neiffer explains. “A lot of different foods allow us to do that, and we’re transparent with the nutrition department so they know what we’re doing related to medical care.”

Thanks to a nutritious diet and state-of-the-art healthcare, the animals at the National Zoo commonly live well beyond their lifespan in the wild. This means the veterinary and nutrition departments must often work together to address age-related ailments, many of which are also common in humans, such as arthritis and vision problems.

For example, one of the zoo’s geriatric Persian onagers — a type of wild ass indigenous to the deserts of Iran — developed a variety of age-related issues that required close collaboration among the husbandry, veterinary, and nutrition departments. “Toward the end of the animal’s life, evaluations were occurring monthly,” Neiffer notes. “We discussed how the onager was doing physically, but also, what was its food consumption like? Has it lost weight? Is there anything we could do with medication to improve its food consumption? Our conversations were about what’s best for the animal in its later years.”

On top of his routine duties as senior nutritionist, Maslanka is involved in a variety of research projects at the National Zoo, sometimes in collaboration with the veterinary department. Among them is the promotion of gut microbiome research (the many bacteria that live in the stomach and intestines) across species, with a closer examination of specific species, such as cheetahs. The big cats have sensitive digestive tracts and are prone to gastritis, and Maslanka hopes to help find the cause of their gastric distress as well as a way to prevent or minimize it by studying their gut microbiome.

“We’re looking at that from a variety of different ways, but one of the most exciting is feeding cheetahs carcasses only, carcasses with a commercially manufactured diet, and a commercially manufactured diet only, and looking at the differences in their microbiome,” he says. “We’ve also looked at cheetahs treated with antibiotics and how we might be able to restore the gut microbiome after an antibiotic treatment. Antibiotics are helpful in treating an infection, but can also wreak havoc on the digestive tract.”

One solution: a fecal microbiota transplant (FMT), a technique used in humans for the treatment of Clostridium difficile infections. As icky as it sounds, FMT is very effective. “We bank feces when an animal is healthy, and refeed it back to the animal so it can more readily restore the gut microbiome after antibiotic treatment or some other type of insult,” Maslanka explains.

The National Zoo has shared the findings of its research in the area of FMT in veterinary journals and at ­conferences, much to the benefit of other zoological facilities. California’s Fresno Chaffee Zoo, for example, reached out to Maslanka about FMT and is now using the procedure to treat intestinal issues in its sloths.

“We wanted to share our information, but also plant a seed regarding fecal microbiota transplant, which isn’t something people think of off the top of their head as a therapy,” Maslanka says. “We’re trying to get practitioners to think about it earlier in the treatment of animals that, for some reason, are not digesting their diets appropriately or have some type of GI dysfunction.”

Another source of research is the zoo’s one-of-a-kind milk repository, the largest collection of exotic animal milk in the world, with more than 17,000 samples across 200 species. Why study milk? By preserving and analyzing milk samples for their nutritional composition, zoo researchers can replicate formulas based on species-specific nutritional needs for use at zoos around the country. One current project involves the analysis of the bacterial composition of rhinoceros milk. (Interestingly, milk has played a role throughout much of Maslanka’s professional life. Early on, he considered pursuing a career in dairy nutrition before falling in love with wildlife nutrition.)

The milk repository also has more practical uses, adds Kendrick. For example, when a screaming hairy armadillo stopped producing milk for her pup, named Sherman, Kendrick worked with the milk repository team to develop a supplemental milk formula, which was hand-fed to Sherman by keepers in the Small Mammal House.

Maslanka faces numerous problems daily as part of his job. One that parents can understand is feeding the zoo’s picky eaters. Like human children, animals will eat a particular food for a while, then suddenly decide they don’t like it anymore. The nutrition department must then reevaluate the types of food a picky animal is receiving and find alternative food items if necessary. Among the pickiest of eaters are giant pandas, whose primary diet is bamboo shoots. Determining the kinds of bamboo that Bao Li and Qing Bao will readily consume proved especially complicated because a panda’s preference can come down not only to the species of bamboo but to where it was grown, and other factors.

“Issues may also arise when an animal is transferred between facilities,” Maslanka says. “Before an animal is transferred to the National Zoo, the previous facility shares the animal’s diet in advance. But when an animal is moved, its entire world is different, including its keeper, its environment, the smells, even day lengths. So, our challenge is to not only transition the animal through all of that, but also get it to eat while going through all of that. We partner with Don Neiffer’s team as the animal goes through the quarantine period in order to ensure that we’re paying close attention to that dietary transition.”

Equally challenging are critical-care cases, which again involves close collaboration between the veterinary and nutrition departments. Every case is different, and a lot of variables come into play, including species, illness, and how the animal responds to treatment. Based on those variables, it’s Maslanka’s job to get the animal to eat, stay hydrated, gain or lose weight, and get medications on board.

“When people ask us about our greatest challenges, it is that we have to become comfortable with an inconsistent day,” Maslanka observes. “The things we do are consistent, but the way that we implement them is different across every animal.”

Despite it all, Maslanka is a man very happy in his job. “I’ve never had a problem getting out of bed in the morning,” he says. “I think a lot of it has to do with being where the rubber meets the road in terms of species and animal conservation. That is our mission at the National Zoo; everything we do contributes to species conservation. And that mission makes it super easy to be jazzed about what we do here every day.”

 

Don Vaughan is a freelance writer whose work has appeared in Writer’s Digest, Mad, Scout Life, and elsewhere. To learn more, visit donaldvaughan.com.

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