Is The Secret to Saving Migratory Birds in the Meal Prep?
Toronto Zoo Announces ZWNF Resident
Assessing the Nutritional Welfare and Status of Animals
Polar Bear Nutrition Guidelines
Fecal Condition Scoring Resource Center
Guidelines for the Humane and Ethical Acquisition and Management of Vertebrate Feeder Animals (Excluding Fish)
Body Condition Scoring Resource Center
Zoo Nutrition Myth: A fruit is a fruit

Vitamin D Status in Wild Toque Macaques (Macaca sinica) in Sri Lanka

The vitamin D receptor is found on most cells, including active immune cells, implying that vitamin D has important biological functions beyond calcium metabolism and bone health. Although captive primates should be given a dietary source of vitamin D, under free-living conditions vitamin D is not a required nutrient, but rather is produced in skin when exposed to UV-B light....

Apple leaves and bark as browse items for herbivorous monogastrics under human care

Many zoological institutions are faced with challenges when developing and providing a diet for their non-ruminant browsing herbivores. The most prominent issue remains providing readily available, safe and sufficient quantities of plant material. Zoos are often forced, usually by climate, to utilize seasonally available, local, appropriate and or novel plant species in order to decrease the effort and expense required...

Predicting nutrient values of elephant grass (Pennisetum purpureum) using near infrared reflectance spectroscopy (NIRS) at Disney’s Animal Kingdom

From May to December each year, the African elephants (Loxodonta africana africana) at Disney’s Animal Kingdom receive elephant grass (Pennisetum purpureum) as a significant portion of their diet. Near infra-red reflectance spectroscopy (NIRS) is used to quickly predict the nutrient quality of the forage. Samples of elephant grass have been collected since 2003 and used to develop calibration equations. As...

A retrospective investigation of the prevalence and significance of hemosiderosis in captive pinnipeds

Iron is a trace element required for the synthesis of haemoglobin and a number of energetic reactions. In most species, iron uptake is primarily regulated by the absorption of iron and protein-addition conversion to ferritin in the mucosal layers of the intestines and the sloughing of mucosal layers when iron levels are replete. However, if this system becomes imbalanced as...

Financial aspects of zoo diet management

Food purchases tend to be one of the greatest expenses, beyond salaries and benefits, for the maintenance of any zoo collection. For this reason, the commissary/food budget is one that receives a lot of attention during the budget planning process. Upon each accreditation inspection, the Association of Zoos and Aquariums (AZA) requires proof of financial stability, including insurance coverage, evidence...

Bamboo as a year-round forage source

Bamboo is a rapidly renewable, nutritionally stable, and in most cases, evergreen forage. Although only rivercane (Arundinaria gigantica) is native to North America, bamboo enthusiasts have imported hundreds of varieties adapted to a wide range of climates and growing zones. We have conducted macronutrient analysis on eleven temperate species collected across all seasons and have analyzed for dry matter, ash,...

Obesity, weight management and dietary analysis in Micronesian kingfishers (Halcyon cinnamomina cinnamomina)

Mortality in captive Micronesian kingfishers (Halcyon cinnamomina cinnamomina) is notably high in age classes that should be peak breeding years. Females, in particular, suffer high rates of mortality earlier than would be expected from examining patterns in related species. Many birds are overweight and sustained weight loss has been difficult to achieve. Body mass for the 2.2 birds in this...

Considerations to maximize nutrient supplementation of feeder insects

Providing a nutritionally appropriate diet to amphibians and other insectivores under human care has long proved challenging. The number of available insect species is limited and typically deficient in key nutrients such as calcium and vitamin A. Until more nutritionally balanced options are available, actions should be undertaken to improve the nutritional quality of feeder insects such as the domestic...

Nutritionally complete food-free diets for primates: potential benefits and concerns

Many zoos and institutions offer nutritionally complete foods (NCF) in the diets of captive primates (Oftedal and Allen, 1996). These foods, which often take the form of extruded biscuits, canned diets or gels, provide a source of important nutrients like protein, fat, fiber, vitamins and minerals, thereby helping to meet minimum estimated nutrient requirements (Oftedal and Allen, 1996; NRC, 2003)....

A comparison of dietary intake in captive, Jamaican Iguanas (Cyclura collei) at four United States zoos

The dietary intake of captive, Jamaican iguanas (Cyclura collei) was measured at four institutions including four U.S. zoos, Indianapolis Zoo (n = 1, 1.2 iguanas), Fort Worth Zoo (n = 2, 2.2 iguanas), Sedgwick County Zoo (n = 3, 1.2 iguanas), and San Diego Zoo – CRES (n = 3, 3.3 iguanas). The diets offered at all four zoos consisted...


Whenever possible, avian parents are tasked with raising their young. Occasionally circumstances dictate that young are pulled for hand rearing. Protocols are in place for different species that indicate food items and amounts to feed as well as developmental indicators and husbandry parameters. Avian species have different diets as adults but many utilize similar food items to feed their young....

Case Study: Iron in Black Rhinoceros Diets: The Impact of Pasture

Over the course of a year, serum ferritin and iron in a black rhinoceros (Diceros bicornis) increased over time, despite a prescribed diet low in iron. To identify additional sources of iron intake, vegetation in the enclosure was analyzed for iron content. Iron concentrations in enclosure samples averaged 736 ppm, well in excess of maximum recommended total-diet concentrations of 300...

Zoo and Wildlife Nutrition Foundation (ZWNF) Announces RESEARCH Grant Opportunity

The Zoo and Wildlife Nutrition Foundation (ZWNF) is a non-profit organization established for the purpose of:
– contributing expertise and providing funds to support zoo and wildlife nutrition programs worldwide,
– furthering the science of zoo nutrition
– facilitating the dissemination of nutrition knowledge, and
– developing the next generation of zoo nutrition leaders

The ZWNF Research Grant supports basic or applied research in the area of zoo and wildlife nutrition.

Grants may be funded up to $1000, and funding may be used to support research programs, including no more than $250 allocated to travel expenses.

Examples of projects eligible for ZWNF Research Grant support include: animal studies evaluating nutrient intake and/or nutrient requirements, evaluation of nutrient content of dietary items, palatability work and other effects of diet/nutrition on behavior, development and/or validation of tools for nutritional assessment such as BCS methods. Examples of projects that are not eligible for ZWNF Research Grant support include: diet surveys without some component described above, studies examining animal physiology without a nutrition component.

Projects should be completed within 1 year of funding receipt, and a final report will be expected within 6 months of that time*.

To apply, submit a short proposal (3 page max, excluding CV and IACUC documentation) including the following information:
– Title and Investigators
– Purpose and Background Information
– Methods (i.e., Design, Analytical Methods, Data Analyses, Expected Results)
– Animal Care and Use Committee (IACUC) approval, if applicable
– CV for investigators
– Funding requested, with details of funding from other sources if required for project completion
– Dissemination plan

– Call for Grants 4/8/18
– Grant proposals due 5/31/18
– Grant awardee/s announced 8/4/18 (at CNS meeting)
– Funding provided by 8/4/18
– Final report due by 12/31/19

Evaluation Criteria:
Proposals will be evaluated by members or designees of ZWNF and AZA NAG. Anyone related to, or who could potentially benefit from grant funding, will be excluded from the selection process. ZWNF board of directors and AZA NAG reviewers are not eligible for grant funding. Eligible proposals will be prioritized based upon those that most clearly meet the AZA NAG’s objectives and priority of funding.

Submit proposals to Barbara Henry, President, ZWNF, Cincinnati Zoo and Botanical Garden, 3400 Vine Street, Cincinnati, OH 45220, or via email at

* Reports on projects or summaries will be viewable on the ZWNF section of the AZA NAG Website and will be included in the ZWNF annual report/updates. ZWNF must be acknowledged in all publications. A contract between the grantee and ZWNF will clearly state these requirements and use of funds. Organizations outside the US will need to provide additional documentation of tax exempt status and financial records.

Influence of fiber source on apparent digestibility, rate passage and fecal consistency in small felids fed a beef-based carnivore diet

In a crossover design, four adult animals, a male and female Amur leopard cat (Prionailurus bengalensis euptilura) and a male and female Turkmenistan caracal (Caracal caracal michaelis) were fed three fresh-frozen beef based diets containing different sources of fiber; beet pulp (BP), fructooligosaccharides/cellulose blend (FOS), and wood cellulose (Solka Floe®) (WC). Assessment included food intake, fecal consistency, animal body weight,...

Elephants: nutrition and dietary husbandry

Elephants are the largest extant herbivores on earth. Although the average weight of adult Asian elephants (Elephas maximus) tends to be less than that of adult African elephants (Loxodonta africana), in the wild their weight ranges overlap (Asian, 1,800-5,000 kg [4,000-11,000 lb]; African, 1,800-6,000 kg [4,000-13,000 lb])33 and are influenced by age, sex, health, and food supply.1,19 Their nutrient needs...

Dietary iron absoption ant the role of tannins in Eastern (Diceros bicornis michaeli) and Southern black rhinoceros (Diceros bicornis minor)

Three diet treatments were fed for at least 6 months at 6 institutions to a total of 11 black rhinoceros to assess the effect of tannins on iron status. Diet treatments were: 1.) a pellet/mixed hay diet, which reflected the diet historically fed; 2.) a pellet/mixed hay diet with quebracho added to the pellets as a source of iron binding...

Energetics and food needs of free-ranging wild mammals, birds, and reptiles

The minimum metabolic rates (“basal” for endotherms and “standard” for ectotherms) of birds, mammals and reptiles are determined mainly by body size (mass), but that explanation may not work for field metabolic rates (FMR, or total daily energy requirement), which include additional energetic costs of activity, temperature regulation, foraging and food digestion, growth and reproduction, and social interactions, along with...

Effect of dietary fiber concentration on apparent digestibility and digesta passage in non-human primates. II. Hindgut-and Foregut fermenting folivores.

Two test diets with different acid detergent fiber (ADF) concentrations (15% ADF, 30% ADF) were fed to seven adult hindgut- and seven adult foregut-fermenting primates. Apparent digestibilities (%) of dietary dry matter (DM), gross energy (GE), and fiber components (neutral detergent fiber [NDF], ADF, hemicellulose [HC], and cellulose [C]) were measured. Rates of digesta transit (TT1) and retention (RGIT) times...

The effect of tannin on the in vitro solubilization of iron

The absorption of dietary iron can be greatly influenced by other constituents in the diet, such as ascorbic acid (vitamin C) and tannins. Ascorbic acid increases the bioavailability of iron by converting Fe3+ to Fe2+, while tannins can reduce the bioavailability of iron by binding to it. Captive herbivorous animals are often impacted by either the addition or absence of...

Complications associated with diet manipulation in callimico (Callimico goeldii)

The diet traditionally fed to Callimico goeldii in North American institutions has included a canned, nutritionally complete food combined with fruits, vegetables and insects. There has been a long-standing question as to whether the diet could be contributing to health issues in this species, particularly renal disease. Although, no direct correlation between the diet and renal disease has been documented,...

Polar Bear Nutrition Guidelines

Polar bears, the most carnivorous of the Ursidae family, prey primarily on ringed seals (Best, 1985; Derocher, et. al, 2000; Stirling and Archibald, 1977).  When brought into captivity, maintaining their nutritional and mental health can be challenging.  Due to the lack of indepth species-specific research, captive polar bear diets must be based on a combination of known requirements of related...

Effect of dietary nutrient level and source on feeder mouse nutrient composition

Whole prey items may contain lower nutrient levels than desired for feeding exotic carnivores. The purpose of this trial was to gather preliminary data on the effect of different dietary treatments on the nutrient composition of mice at various ages. Dietary enrichment with vitamin E and chelated minerals in general did not improve total body levels of most nutrients, but...

Associations of Zoos & Aquarium’s animal care manuals: What is the nutrition advisory group’s role?

The Species Survival Plan ® (SSP) or Taxon Advisory Group (TAG) is responsible for creating and updating information on their prospective species. It is important to assemble this information in a systematic and consistent manner. In 2005, the Association of Zoo & Aquariums (AZA) created standardized guidelines. Considering the exact nutrient requirements of many exotic animals held in captivity are...