This publication is based on a paper presented at the First European Zoo Nutrition Meeting held in Rotterdam, Netherlands between 8–11 January 1999.
The first nutritionists associated with North American zoos appeared in the mid-1970s and in Europe in the 1980s. Since that time, the number of nutritionists working at zoos has slowly increased. Captive exotic animal management has always included nutrition, but in the last 20 yr, several zoos have built nutrition programs and substantially developed those that already existed. There are basic needs for the foundation of a nutrition program including an interested and capable person or group, some rudimentary equipment, an understanding of the history of the animal collection and its management, and an organizational structure conducive for properly documenting the development. Beyond this, development of a nutrition program hinges on the stability of the initial structure and its direction is determined by reasons surrounding its inception. Properly developed, a nutrition program can contribute to the multidisciplinary care and management of the animals in our charge.
Although zoo nutrition is a relatively new field, its importance is growing quickly among the zoo’s community. All of us are aware that one of the roles of zoos is to preserve endangered species and take an active part in conservation. Beyond that, we are charged to take an active role in educating the visitors who enter our zoos in order to substantially increase the conservation effort outside of the zoo’s immediate boundaries. Nutrition represents one of the many interrelated parts that determine the wellbeing of an animal.1,4 If any of the parts fail, animal health may be compromised, and, with it, our ability to educate the public and promote conservation of endangered species.
When starting to work on nutrition at a zoo, the last thing to be done actually may be the “nutrition” itself. A foundation and structure must be created first, upon which to build a nutrition program. That foundation can begin by demonstrating the need for a nutrition program. That “need” may take the form of evaluating current diet items for quality and/or price, the need to streamline food processing operations, or, most directly, the examination of nutritional/metabolic problems of the animals in the collection. If the zoo has already examined use of a “nutritional consultant” or similar person, many of the staff may already be aware of the “need” which exists. Regardless of how or why the “need” is expressed, institution-wide support of a nutrition program is imperative to its success. Often, that support is not present at the outset and develops as the benefits of such a service are displayed over time. Once the impetus to develop a nutrition program exists and receives the appropriate encouragement (moral, financial, or both), there are several directions the program can take based on why it was developed (price, quality, or operational evaluation, diet evaluation and/or adjustment, etc.). Development of the program often proceeds based on the reasons it was conceived.
Advantages of a Nutrition Program
When building a nutrition program, presenting some of its advantages may be beneficial to gaining financial and moral support. The advantages of having a nutrition program at a zoo can be approached from two perspectives: from the animal’s point of view and from the institution’s point of view.
From the animal’s point of view, a nutritionist can provide the expertise to minimize the incidence of health problems and improve the animal’s quality of life. To that end, the nutritionist can ensure that the food offered is of the best quality for the animals. A nutrition program can allow better control over the items, thus the nutrients, delivered to an individual animal. The nutritionist can contribute to better management of the entire diet—from its formulation to the spatial and temporal distribution of the diet items. This can allow for more active animals and can potentially minimize the incidence of stereotypic behaviors, aggression, and/or weight management issues. Additionally, if the diet more closely meets the nutrient requirements of the animal, it may allow for more successful reproductive efforts and/or increased longevity.
From the institution’s point of view, a nutritionist can provide adequate diets for their animals. Beyond that, a nutritionist can help ensure that the diet formulated is the diet offered, and determine if the diet offered is the diet consumed. This can allow for better maintenance of the collection, which ultimately provides the experience for the zoo visitor and the revenue of the institution. Increased knowledge regarding what and how much the animals eat can allow for better control of expenses. A nutritionist can allow for better organization through fostering communication between the staff responsible for preparing diets and the animal management staff, thereby increasing efficiency and effectiveness. They also can contribute valuable information when special animal problems arise (in coordination with keepers, curators, veterinarians, etc.). A nutritionist can also provide the expertise to allow for exchanges among food items which may be similar in nutrient content but more affordable. Good nutritional status of animals ultimately leads to better health of the animals, potentially minimizing veterinary care and costs as well.
How to Start—The Foundation
There are a few prerequisites to develop a nutrition program which begin at a very basic level: (1) a person (more or less qualified) willing to work and learn, with (2) lots of energy, enthusiasm, and patience, and (3) a salary or other financial aid. Beyond that, there are a few things which assist the endeavor immensely: (1) tables of requirements and food nutrient contents, (2) a scale (or scales), and (3) a computer.
A person can begin working part time on nutrition issues while filling another role at the zoo. This may allow the person to develop good working relationships with the curatorial and keeper staff prior to working intensively with nutrition. As the nutrition aspect of that person’s job becomes more prominent (slowly or quickly), the institution and the individual can continue to grow with the increased responsibilities and expectations.
Before doing anything, it is important to become familiar with the institution’s policies—their goal and mission statements, their organizational structure (formal and informal), how operations work in each area, and all of the aspects associated with diet preparation and distribution. From this, one can get an idea of what is working well, what can work well with a minor alteration, and what can work well with a more extensive change. It is also basic to listen to staff opinions and experiences. The keepers work with their animals on a daily basis, many have been in the zoo for years, and know not only their animals but also how the zoo functions. Some changes may have been tried previously, and did not work. Long-time keepers can provide this historic perspective, which can save time and wasted effort. This background information is pivotal in providing a foundation for a nutrition program and remains important as the program grows and develops.
The First Steps—The Framework
Once the initial background information is gathered and the foundation has been set, work can begin with some basic skills and knowledge. Good organizational skills are critical to document progression of diet formulations—basic communications, what worked, what did not work, why. The skills of the nutritionist and those of the diet preparation staff should be well coordinated. If utilized, the commissary must be well organized and trained with respect to sanitation—food handling and storage. Diet preparation also must be organized, sanitary, detailed, and dynamic (to account for changes that occur).
Again, it is critical that everyone understands the importance of good nutrition, especially the keeper staff. They are often responsible for diet preparation and observation of diet consumption, and they know the animals around the zoo better than anyone. Their understanding of the importance of adequate nutrition for their animals is crucial for the success of the nutrition program.
Diet evaluation itself may not fit into the first steps of developing the nutrition program. If the basic skills are lacking, it may be worthless to design diets that meet probable requirements because they may not be utilized correctly or at all. In the development of the program, it may be more important to concentrate on the basic first steps of gathering background information, communication of the purposes of the nutrition program, and development of organizational skills. It may be more important to concentrate on these basic first steps and develop a framework upon which to build later.
The Next Steps—Filling the Framework
When developing a nutrition program, financial support is necessary. At the outset, this may represent a salary from the zoo. In some cases, nutritionists have started as volunteers and slowly developed into their current salaried positions over a period of years. After a certain point, financial support over and above a salary becomes important. If that support does not come from within the zoo, external support can be sought. This support can come from manufacturers (food or equipment), private donors, grant or endowment programs, etc. and take the form of concrete financial support or the donation of equipment and/or services that may be of assistance to the nutritionist.
There are many ways to actually start working on diet evaluation, primarily based on the reasons why the program was created. A stepwise systematic approach (taking one area at a time) may be very successful to progress through diet evaluations of the entire zoo and improve animal husbandry over an extended period.3 However, if the program was created due to specific dietary evaluation needs stemming from specific nutrition-related disorders, a troubleshooting or problem-solving approach may be needed to get started. Each area and group of animals have unique nutritional issues, from how the diets are prepared and offered to the specific nutritional needs of the animals. Diets not only need to be formulated to meet the nutritional needs of the animals (a topic better discussed and more adequately addressed elsewhere), but attention must be paid to ensure that the diets fit well into the daily routines of all the areas which will be preparing/handling the diets on a daily basis. In this way, the role of the nutrition program is not only to provide adequate nutrition to the animals in the zoo collection, but, additionally, to do so in a practical manner. Additionally, by considering the behavioral needs of the animals being fed, as well as their nutritional needs, the nutrition program can provide a well-rounded approach to diet formulation for the good of the animal collection.
As the nutrition program develops, the guidance and advice of other nutritionists and experts can be invaluable. These resources can be found at other zoos, zoo-related organizations (AAZK, etc.) universities, and private research facilities, to name only a few, on a worldwide scale. Keep in mind that “progress in [the field of nutrition] can be best made through the cooperative efforts of qualified individuals,” from the most basic to the most complex endeavors.5
Potential Problems—Reinforcing the Framework
Every institution is different, but there may be some common problems that arise. When trying to convey the need for a nutrition program, the benefits of such a program should be presented and evaluated. Nutrition problems are not always detected in a timely fashion (at postmortem exam or after a long nutritional insult has occurred)4 and the advantages of a nutrition program similarly materialize over the long term. For this reason, it may be difficult for the zoo to immediately see the advantages of a nutritionist. The evaluation of the benefits of a nutrition program may be based on decreased veterinary costs, decreased incidence of health problems, decreased feed costs, and/or increased efficiency. Although the best initial approach may be to begin concentrating on the financial aspects, keep in mind that they may not materialize immediately.
Many keepers may have been working at an institution for a long time and may not have any experience with “formal” nutrition or a nutritionist. They may not understand that there is a difference in the amount of nutrients provided in 2.5 g of egg vs. 3.0 g of egg (for example), and why this may be an important consideration for some species or individuals and not others. For these reasons, they need to be introduced to the concept of nutrition, educated, and motivated as to the goals of a nutrition program, how the program can assist them to achieve their own goals, and allowed time to adapt to the changes that may occur. In many zoos, this introduction/education may be necessary for other members of the multidisciplinary team responsible for animal care as well.
If there is a lack of organization, changes can be made more complicated or even impossible. In some cases, it is up to the nutritionist to be inventive and find new ways to organize and present information so that it is clear. Being able to track changes, what worked, and what did not, are imperative to avoid making the same mistake twice.
Zoos are not always ready to support a nutritionist financially and it may be important to get external support. However, this is not always easy and may take a considerable amount of time and effort. Remember that financial aid can be found in the form of a monetary donation or in the form of a piece of equipment. Both may equally satisfy the imminent need.
When animal nutrition is included as a curriculum at many universities, it examines and teaches about a broad range of domestic animals. There are few curricula that examine animal nutrition widely and, further, many students who might otherwise be interested in pursuing such a career do not know it exists as a viable option. For this reason, it is sometimes difficult to get help—specifically to assist with the aspects of the job which demand a nutrition background. This stresses the importance of collaborating with other nutritionists and similar resources. Local experts in universities can also provide advice, technical support, and analysis of food items (if needed).
Nutrition programs within zoos exist on a gradient from zoo nutrition services which have staffs of 10 or more people, formulate their own pelleted and gel diets, and have well-equipped labs to analyze feeds, to a single volunteer working to improve diets using tables with nutrient content information, a scale, and as many spare moments as can be found in their day. When starting out, zoos should focus on adapting a nutrition program to the resources of their institution, not a perceived “ideal.” Building a successful nutrition program takes a period of years, even decades. If the foundation is firm and development takes place in a stepwise fashion, an effective nutrition program can be created, which is invaluable to successful maintenance of exotic animals in captivity.
1. Dierenfeld, E.S. 1997. Captive wild animal nutrition: a historical perspective. Proc. Nutr. Soc. 56:989–999.
2. Dierenfeld, E.S. 1996. Nutritional wisdom: adding the science to the art. Zoo Biol. 15:447–448.
3. Fridgett, A.L. and A.T.C. Feistner. 1997. Non-invasive methods for nutritional research at the Jersey Wildlife Preservation Trust. Proc. AZA Nutr. Advisory Group Conf., Fort Worth, TX.
4. Oftedal, O.T. and M.E. Allen. 1996. Nutrition and dietary evaluation in zoos. In: Wild Mammals in Captivity. D.G. Kleimann, M.E. Allen, K.V. Thompson, and S. Lumpkin, eds. Chicago, University of Chicago Press. Pp 109–116.
5. Ullrey, D. E. 1996. Skepticism and science: responsibilities of the comparative nutritionist. Zoo. Biol. 15:449–453.