CHAPTER
49
Feeding and Nutrition of Anteaters
Eduardo V. Valdes and Andrea Brenes Soto
The superorder Xenarthra (former Edentata) is grouped
into two orders, Cingulata (armadillos) and Pilosa (anteaters and sloths). These are special mammals that show
unique traits: (1) the existence of secondary articulations called xenarthrales located between the lumbar
vertebrae and the spinal column; (2) the presence of
fused pelvic bones; and (3) very low metabolic rate and
variable body temperatures, which allow xenarthrans to
conserve energy. They are also highly specialized, but
diverse in terms of dietary needs. Xenarthrans include
strict folivores such as the three-toed sloth (Bradypodidae), omnivore-generalists such as the two-toed sloth
(Choloepus spp.), specialized carnivores such as the giant
anteater (Mymecophaga tridactyla), and the tamanduas
(Tamandua tetradactyla, T. mexicana). Armadillos vary in
their diet, with certain species feeding mainly on ants
and termites but others, such as the common Dasypus
novemcinctus, are omnivorous.
ANTEATERS
A few studies have been published on the dietary habits
of anteaters that show the type and composition of prey
selected by these animals in the wild. The natural diet
of giant anteaters (Mymecophaga tridactyla) is composed
96% of ants and 4% of termites (Camponotus and Solenopsis spp.).16,23 In Brazil, this species of anteater may
consume approximately nine different ant species, but
in June they switch to consume termites.11 Some anteaters, such as the tamandua, are highly specialized predators, consuming mainly ants and termites, but preferring
the reproductive and worker castes.10,17 Occasionally,
anteaters will consume other invertebrates but avoid
prey with large jaws, strong chemical defenses, or spiny
bodies. Anteater tongues may reach out 60 cm with an
amazing mobility (150 times/min) and may consume
up to 30,000 ants/day.27 Silky anteaters (Cyclopes
378
didactylus), a nocturnal animal that lives mainly in the
trees, will consume termites and beetles, but their main
diet is ants. Medical issues (e.g., hair loss, conjunctivitis)
has been observed when feeding silky anteaters captive
diets in Peru consisting of a mixture of dog milk replacer,
sunflower oil, barley, and yeast, with vitamin and
mineral supplements.26 Studies on the nutrient content
of several species of termites have found that fat, ash,
and nitrogen levels vary based on termite castes. Species
that tended to be high in ash were low in fat and nitrogen. In the case of Grigiotermes metoecus, they are high
in ash because of geophagy, with soldiers low in fat, but
reproductive and alate forms were high in fat. Alate
nymphs of Procornitermes araujoi had 24% fat; soldiers
and workers of Armitermes had 42% ash and 3.64%
nitrogen. In their natural environment, tamanduas
feed almost exclusively (95% by volume) on termites
(Nasutitermes spp.) and ants (Crematogaster and Camponotus spp.), with the rest of the diet consisting of
stingless bees, heteropterans, unidentified insect pupae,
and seeds.2
NUTRITIONAL CONSIDERATIONS
Nutritional Disorders
There have been a number of varied disorders seen in
anteater species relating to nutrition. Rear limb paresis
progressing to complete flaccid paralysis and extensive
hyperostosis of the thoracic, lumbar, and coccygeal vertebrae has been reported in T. mexicalis.3 The symptoms
probably were related to vitamin A toxicosis or excess
vitamin D and/or calcium.21 Similar lesions have been
reported in tamanduas in European zoos that had
been consuming a diet with high levels of vitamin
A (>20,000 IU/kg dry matter [DM]).5 However, in one
study of the natural diet of T. tetradactyla, the authors
Chapter 49 • Feeding and Nutrition of Anteaters
reported that the mean vitamin A value of Nasutitermes
spp. was 24,773 IU/kg. Most of the invertebrates used
in zoo diets will have much lower vitamin A levels,
ranging from approximately 60 IU/kg (snails) to
2400 IU/kg (earthworms, crickets).5,25 Requirements of
vitamin A in domestic animals such as dogs and cats
range from 5000 to 10,000 IU/kg DM.20
Other nutritional problems, including vitamin K
deficiency, liquid feces probably caused by high levels
of grain and lactose products in the diets, and constipation caused by lack of fiber and tongue problems, have
been observed in anteaters kept in North American and
European zoos.18,19 Similar to domestic cats, low blood
and plasma taurine concentrations have been associated
with dilated cardiomyopathy in giant anteaters and used
as early diagnostic indicators.1,28 Taurine whole blood
levels below 300 nmol/mL, (normal range = 300 to
600 nmol/mL) and plasma levels below 60 nmol/mL
(normal range = 60 to 120 nmol/mL) might be associated with the presence of cardiomyopathies in giant
anteaters. The use of dog chow as a food item has been
given as the reason for the taurine-deficient dilated cardiomyopathy in giant anteaters.1 Dogs, unlike cats, do
not require taurine in their diet, provided there are sufficient sulfur amino acids for taurine synthesis. Similarly, symptoms of taurine deficiency have been reported
in young tamandua when fed cat and dog milk replacers.15 Vitamin K deficiencies in anteaters had been
reported in the past. This suggested that ant and termite
eaters have the tendency to have hemorrhagic problems
unless supplemented, particularly when the animals
had been treated with antibiotics.12 In the last decade,
diabetes has been reported in T. tetradactyla in zoological institutions.24 In one case, the animal had been fed
a mixture of primate and feline dry chows (see later). At
the Cleveland Zoo, two tamanduas have been diagnosed with diabetes. Retrospective studies on the health
and nutrition of tamandua in Association of Zoos
and Aquariums (AZA) institutions are presently being
conducted at Ohio State University–Cleveland Metro
Parks Zoo.4
nutritional needs and nutrient requirements of insectivorous mammals, presenting another significant challenge for captive-kept animals. Because anteaters are
specialized carnivores, the nutrient requirements established for domestic cats and dogs may be used as models
when developing and evaluating the nutritional value
of their diets in captivity. These data might be able to
provide a range of nutrient values that can be used as
general guidelines. Historically, in zoological institutions, anteaters are fed diets that consist of mixtures of
different ingredients; these may include milk products,
eggs, ground raw meat (horse or beef), dog chow,
canned dog food, yogurt, commercial carnivore diets,
multivitamins, trace mineral supplements, human
protein supplements, and fruits (e.g., ripe bananas,
oranges, limes, avocados, mangos). Normally, the ingredients were offered as a gruel mix, with additional
vitamin K possibly added. Diets that include these
ingredients have been previously described and were
extensively used when zoos first added anteaters to their
animal collections.7-9,12-14 These diets, developed at
Lincoln Park Zoo, led to some success in maintaining
and reproducing anteaters. However, until the early
1990s, North American and South American zoos had
a poor record of keeping and reproducing tamanduas.3
Poor survival during the early years was probably related
to their specialized dietary requirements. Several problems with the first diets used in zoos led to the development of new diets in the early 1990s.
One of the diets, developed in the early 1990s was
based on a study of the nutrient composition of the
natural diet of tamandua in the Llanos of Venezuela.21
The goal of this study was to obtain baseline information through the collection and analysis of termites, one
of the tamanduas’ main prey items, as well as tamandua
stomach contents. The summary of the results is given
in Table 49-1. We found that the consumed diet of freeranging tamandua contained 50.9% crude protein,
11.2% fat, 13.9% ash, 31.3% acid detergent fiber,
0.11% calcium, 0.41% phosphorus, 2.52 µg/g retinol,
44.35 µg/g α-tocopherol, and 4.58 kcal/g of gross
energy on a dry matter basis. This information was used
to help with the formulation of tamandua and anteater
zoo diets in North American institutions and elsewhere.
For example, after adjusting nutrient levels (e.g.,
calcium), the Toronto Zoo was able to replace or modify
the traditional Lincoln Park Zoo diets (Table 49-2). This
or similar diets are also used in other North American
and Central and South American zoos.22 With the development of commercial insectivore pellets (see Table
49-2), feeding anteaters has become easier, although
Anteater Diets in Zoos
It is difficult to mimic the natural anteater diet in zoos
by providing specific ants and termites to consume, as
in the free-ranging state, so alternative food choices
available in the market are used to develop their diets.
The selection of these foods becomes a challenge if we
want to provide good nutrition and be able to satisfy
behavioral needs. However, little is known of the exact
379
380
Section 6 • Xenarthra
TABLE 49-1 Selected Chemical Analyses of Termites (Nasutitermes spp.) Consumed by Tamandua (T. tetradactyla)
in Their Natural Environment: Comparison With Tamandua Stomach Contents
TERMITES
Analysis
DM (%)
CP (%)
Fat (%)
GE (kcal/g)
NDF (%)
ADF (%)
Lignin (%)
Ash (%)
Ca (%)
P (%)
Mg (%)
Fe (ppm)
Zn (ppm)
Retinol (µ/g)*
α-Tocopherol (µg/g)
Workers
Alates
Overall
24.7
66.7
2.2
—
—
27
—
4.6
0.2
0.4
0.13
—
—
—
—
41
48.8
40.2
6.9
23.4
13
13
3.7
0.24
0.36
0.15
394
144
0.65
40.4
29.4
58.2
15
6
30.8
25
17.2
4.1
0.26
0.38
0.14
246
184
7.4
92.5
Stomach Contents
17.8
50.8
11.2
4.6
32.2
31.3
16.1
13.8
0.1
0.4
0.1
652
163
2.5
44.3
ADF, Acid detergent fiber; CP, crude protein; DM, dry matter; GE, gross energy; NDF, neutral detergent fiber.
*Conversion factor: 0.3 µg retinol = 1 IU vitamin A; 1 mg α-tocopherol = 1.49 IU vitamin E.
not perfect. The gruel-type diets such as the one developed in Toronto, are better than previous anteater gruel
diets because the nutrient profile is generally closer to
the one found in the natural diet, avoiding excesses, like
the ones previously reported.3 However, this diet still
lacks sufficient amount of daily fiber (acid detergent
fiber [ADF]) if compared with the natural diet (see Table
49-1). The addition of artificial fiber (e.g., Solka-Floc,
International Fiber, Tonawanda, NY) or commercial
insectivore pellets to the gruel diets may improve their
fiber content (see Table 49-2).
During the 1990s, a new diet was introduced aimed
at simplifying the giant anteater diet through the elimination of milk products, including yogurt, and the elimination of raw meat, among other dietary ingredients.
These changes also aimed to improve the nutrient concentrations, eliminate the presence of potentially
harmful components, improve diet consistency, and
improve stool consistency. This diet consisted of a finely
ground mixture of equal proportions of a dry cat chow
and a higher fiber primate chow.6 The diet may be
offered dry or wet (thin paste consistency with the addition of water). The composition of this diet mix is given
in Table 49-2. Certainly, this diet has the advantage of
being simple to prepare in contrast to the gruel-type
mixes. However, simplicity does not mean that the diet
is better in terms of nutrients when compared with a
more natural anteater diet (see Table 49-1). The main
drawback of this mix is the very high level of starch
(calculated value above 20%) and other soluble carbohydrates (above 20%). Starch content is extremely low
in the natural diet of specialized carnivores, such as
tamandua and giant anteaters. Because of the reported
cases of diabetes in tamandua, the use of this mix of
traditional high-starch commercial diets (primate and
feline chow) is not recommended.
With the development of commercial insectivore
pellets in the early 2000s (see Table 49-2), feeding anteaters has become easier. This relatively new commercial insectivore pellet, with less than 10% starch content,
is a better alternative to the primate or feline chows.
Some institutions will use a combination of the new
gruels (Box 49-1) and the commercial insectivore pellet.
Although the diets presented in Table 49-2 and Box 49-1
represent an improvement from the original gruel diets
from the 1970s, they are still highly digestible, unlike
the natural anteater diets. A study of the metabolic rate
and food digestibility in free-living southern tamandua
has found that the dry matter digestibility is low, averaging 50%, mainly because of the presence in the digesta
of large portions (51.5%) of matter with little metabolizable energy content, such as sand and fiber.2 The field
Chapter 49 • Feeding and Nutrition of Anteaters
381
TABLE 49-2 Chemical Composition of Selected Tamandua Diets
DIET
Analysis
Tamandua Gruel*
Complete Tamandua†
Mazuri Insectivore pellets‡
H2O, %
DM, %
CP, %
ADF, %
NDF, %
Lignin
Starch, %
Sugar, %
C fat, %
Ash, %
Ca, %
P, %
Mg, %
K, %
Na, %
Fe, ppm
Zn, ppm
Cu, ppm
Mn, ppm
Mo, ppm
S, %
Cl, %
Se, ppm
Co, ppm
Vitamin E (mg/kg)
Vitamin A (IU/kg)
Vitamin D (IU/g)
Vitamin C (mg/kg)
GE (cal/g)
Sat FA g/100 g
PUFA g/100 g
Omega-3, g/100 g
Omega-6, g/100 g
Lysine, %
79
21
52.2
3.32
4.74
nr
2.8
24.6
15.6
5.96
0.9
0.69
0.08
0.85
0.376
145
58
11
7
0.3
0.52
0.58
1.34
0.16
541
2964
0.112
0.48
5789
5.99
3.43
1.53
1.8
3.74
74.4
25.6
31.6
10.7
23.7
nr
6.8
19.3
13.5
7.53
1.25
0.85
0.13
0.85
0.388
329
101
20
72
1.2
0.43
0.62
0.48
0.62
82.43
4960
2.31
24.32
4766
1.24
0.87
0.06
0.77
0.51
4.1
95.9
31
20.1
30.8
4.1
13.1
2.7
14.6
9.31
1.26
0.97
0.17
0.82
0.361
312
115
24
90
0.9
0.46
nr
0.64
1.49
84.8
7576
nd
nd
4449
4.27
3.75
0.34
3.2
1.71
DFPC 50 : 50 Diet§
NRC Reference¶ Ranges
6.51
93.5
30.9
—
—
—
20||
—
14.7
6.3
1.07
0.84
—
—
—
231
188
—
—
—
—
—
—
—
196.3
18,137
—
—
—
—
—
—
—
1.64
—
—
25-50
—
—
—
—
—
13.8-22.5
—
0.72-1
0.64-0.75
100-150
1-1.3
170-200
7.5-20
15-18.5
1.2-7.5
1.2
—
—
—
75-87
—
7.5 -10
250-379
1.4-1.75
—
—
—
—
—
—
0.88
*Disney’s Animal Kingdom gruel diet.
†
Disney’s Animal Kingdom Complete Tamandua diet (mix of gruel and commercial insectivore diet).
‡
Mazuri Feeds.
§
DFPC = 50:50 mix of Iams Cat Food, Dry, and Marion Zoological Leafeater Primate Diet, Dry.6
||
Calculated value.
¶
NRC requirements: Protein, fat, Ca, P, g/1000 kcal metabolizable energy (ME); Mg, Na, Fe, Cu, Zn, mg/1000 kcal ME; vitamin A = µg
RE/1000 kcal ME, vitamin E = mg/1000 kcal ME; vitamin D = cholecalciferol = µg/1000 kcal ME; daily ME for exotic cats = 55-260 × kg body
weight (BW)0.75; daily ME for dogs = 95-200 × kg BW0.75; daily ME for T. tetradactyla = 107 kcal/day (5.1 kg BW).
382
Section 6 • Xenarthra
BOX 49-1 Acknowledgment
Sample Anteater Diets
Ingredients
g/day
Katie Sullivan is greatly acknowledged for her assistance
with the manuscript.
Disney’s Animal Kingdom Gruel Diet
Beef heart
Water
Banana
Chitin
Vitamin B complex with B12*
Honey
Hardboiled egg
Nutrigro powder†
Flax
Vitamin E powder (40 IU/g)
Calcium carbonate
Vitamin C powder
213
128
21
0.3
0.6
5
17
17
4
1.5
0.9
0.6
Zoological Society of San Diego Giant Anteater Diet
Mazuri Insectivore Diet 5MK8‡
750
Disney’s Animal Kingdom Complete Tamandua Diet
Mazuri Insectivore Diet 5MK8
DAK Tamandua Liquid Diet
Flax Oil
Jello, sugar-free
Waxworm
Superworm
Avocado
Banana
Mango
293
161
5
25
3.2
14.6
8.1
67
40
Zoological Society of San Diego Complete
Tamandua Diet
Banana
Water
Mazuri Insectivore Diet 5MK8
Mealworms§
2.74
710
216
0.17
*Goldline, 0.6 g = half-tablet.
†
Grober.
‡
Mazuri Feeds.
§
Zoological Society of San Diego mealworms fed a high-calcium diet.
metabolic rate of tamandua was found to be approximately 42% lower than that expected for a nonherbivorous eutherian mammal of its size, with a mean energy
expenditure of 449 kJ/kg/day or 107 kcal/day. Based on
this information, it is important to adjust the present
diets used in zoos to meet the lower energy requirements and lower digestibility coefficients found in the
natural environment. The latter might be achieved by
adding a source of indigestible fiber, such as chitin or
cellulose, to the new gruels or insectivore pellets.
REFERENCES
1. Aguilar RF, Dunker F, Garner M: Dilated cardiomyopathy in two
giant anteaters (Myrmecophaga tridactyla). In Kirk Baer C, editor:
Proceedings American Association of Zoo Veterinarians, 2002,
Milwaukee, October 5–10, 2002, Wisconsin, pp 169–172.
2. Bosque C, Hernandez M, Pannier E: Metabolic rate and food
digestibility in free-living southern tamanduas (Mammallia:myrm
ecophagidae). In Proceedings of the first comparative nutrition
society symposium, Leesburg, Virginia, August 2-6, 1996, Published by Comparative Nutrition Society, pp 16–17.
3. Crawshaw GM, Oyarzun S: Vertebral hyperostosis in anteaters
(Tamandua tetradactyla and Tamandua mexicana): Possible hypervitaminosis A and/or D. J Zoo Wildl Med 27:158–169, 1996.
4. Dennis P: Investigation of diabetes in tamandua in AZA insti­
tutions, 2010 (http://www.clemetzoo.com/whats_new/research.
asp).
5. Dierenfeld ES, Barker D, McNamara TS, et al: Vitamin A and
insectivore nutrition. Verh Ber Erkrg Zootiere 37:245–249, 1995.
6. Edwards MS, Lewandowski A: Preliminary observations of a new
diet for giant anteaters (Myrmecophaga tetradactyla). Proc Am
Assoc Zoo VetLeesburg, Virginia 496–499, 1996.
7. Divers BJ: Edentata: Diseases. In Fowler ME, editor: Zoo and
wildlife animal medicine, ed 2, Philadelphia, 1986, W. B. Saunders, pp 621–630.
8. Gillespie D: Edentata: Diseases. In Fowler ME, editor: Zoo and
wild animal medicine: current therapy, Philadelphia, 1993, W. B.
Saunders, pp 304–309.
9. Gillespie D: Xenarthra: edentata (anteaters, armadillos, sloths).
In Fowler ME, Miller RE, editors: Zoo and wild animal
medicine: current therapy, Philadelphia, 2003, W. B. Saunders,
pp 397–407.
10. Lubin YD, Montgomery GG: Defenses of Nasutitermes termites
(Isoptera termitidae) against tamandua anteaters (Edentata, Myrmecophagidae). Biotropica 13:66–76, 1981.
11. Meri I, De Miranda G, Arada A: [Dieta de tamandua bandeira
(Myrmecophaga tridactyla) no pantanal da Nhecolondia, Brasil.]
Edentata 5:29–33, 2003.
12. Merritt DA: Edentate diets currently in use at Lincoln Park Zoo,
Chicago. Int Zoo Yb 10:136–138, 1970.
13. Merritt DA: The lesser anteater (Tamndua tetradactyla) in captivity.
Int Zoo Yb 15:41–45, 1975.
14. Merrit DA: The nutrition of edentates. Int Zoo Yb 16:38–46, 1976.
15. Miranda M, Loyola M, Cordeiro M, Cancado R: [Deficiencia de
taurina en filote de tamandua-Mirim (Tamandua tetradactyla) Alimentado com substitutes de leite para caes e gatos.] Ciencia Anim
Brasila 9:1004–1009, 2008.
16. Montgomery GG: Impact of vermilinguas (Cydopes, Tamandua:
Xenarthtra = Edentata) on arboreal ant populations. In Montgomery GG, editor: The evolution and ecology of armadillos, sloths,
and vermilinguas, Washington DC, 1986, Smithsonian Institution Press, pp 351–363.
17. Montgomery GG: Movements, foraging and good habits of the
four extant species of neotropical vermilinguas (Mammalia: Myrmecophagidae). In Montgomery GG, editor: The evolution and
ecology of armadillos, sloths, and vermilinguas, Washington DC,
1986, Smithsonian Institution Press, pp 365–377.
18. Moford S, Meyers M: Giant anteater (Mymecopha tridactyla) diet
survey. Edentata 5:5–20, 2003.
Chapter 49 • Feeding and Nutrition of Anteaters
19. Moford S, Meyers M: Giant anteater (Mymecopha tridactyla) health
care survey. Edentata 5:20–24, 2003.
20. National Research Council: Nutrient requirements of dogs and
cats, Washington, DC, 2006, National Academies Press.
21. Oyarzun SE, Crawshaw GJ, Valdes EV: Nutrition of the tamandua:
1. Nutrient composition of termites (Nasutitermes spp.) and
stomach contents from wild tamanduas (Tamandua tetradactyla).
Zoo Biol 15:509–524, 1996.
22. Perez JG, Gonzalez GG: [Evaluacion de una dieta para tamanduas
(Tamandua spp) utilizada en el Jardin Zoologico de Rosario,
Argentina y el Zoologico de la Aurora, Guatemala.] Edentata
6:43–50, 2006.
23. Redford KH: Feeding and food preference in captive and wild
giant anteaters (Mymecophaga tridactila). J Zool 205:559–572,
1985.
24. Stetter M: Personal communication, 2010.
25. Sullivan KE, Livingston S, Valdes EV: Vitamin A supplementation
via cricket dusting: The effects of dusting fed and fasting crickets
of three sizes using two different supplements on nutrient content.
In Ward A, Treiber K, Schmidt D, Coslik A, Maslanka M, editors:
Proceedings of the Eighth Conference of the Association of Zoos
and Aquariums Nutrition Advisory Group on Zoo and Wildlife
Nutrition, pp 160–162. 2009. Tulsa, OK, 24-28 October 2009,
Published by Nutrition Advisory Group, pp 160–162.
26. Vargas A: [Formulacion de dietas en cautiverio de serafin del
platanal (Cyclopes didactylus) en el parquet zoologico Huachipas.]
Edentata 7:18–23, 2006.
27. Wainwright M: The natural history of Costa Rican mammals,
Miami, 2003, Zona Tropical.
28. Wilson ED, Dunker F, Garner M, et al: Taurine deficiency associated dilated cardiomyopathy in giant anteaters (Myrmecophaga
tridactyla): Preliminary results and diagnostics. Proc Am Assoc
Zoo Vet 155–159, 2003.
383