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Feeding Behavior and Nutrition of the African Pygmy Hedgehog (Atelerix albiventris)
Fe e ding Behavior a nd Nutrition of the Afric a n P ygmy He dgeho g (A t e l e r i x a l b i v e n t r i s ) Ellen S. Dierenfeld, PhD, CNS KEYWORDS Feeding Hedgehog Insectivore Nutrition Omnivore
At least four genera and 14 species of hedgehogs are widespread throughout Europe, Russia, China, and Africa. Adult hedgehogs weigh 400 to 1100 g.1 African pygmy hedgehogs, Atelerix albiventris, are distributed from the southern Sahara through Central and East Africa. Weighing 250 to 700 g, pygmy hedgehogs are popular exotic pets in North America. Hedgehogs are found in a variety of habitats, including deserts, steppes, and forests. They dig burrows; seek shelter under brush piles, logs, rocks, tree roots, and buildings; and need hiding places and nesting materials in captivity. European species hibernate during the coldest months of the year; African hedgehogs typically do not hibernate, but they can hibernate in cool environments.2 Hibernation, however, is not recommended for captive hedgehogs, because the decrease in metabolism leaves them more susceptible to infection; thus, animals should be maintained at temperatures higher than 18 C.2 GENERAL FEEDING BEHAVIORS AND DIGESTIVE PHYSIOLOGY
Although classified as members of the order Insectivora, hedgehogs are quite omnivorous, eating a variety of invertebrates (eg, beetles, millipedes, worms, slugs, snails) in addition to small vertebrate prey (eg, frogs, snakes, lizards, eggs, young birds, mice) and plants.1,3 Limited general information published on the dietary habits of African hedgehogs4–6 suggests that they are also opportunistic omnivores, consuming a more varied diet based on food availability. Hedgehogs are nocturnal, starting to feed at dusk. Because they are good swimmers and active climbers, they have ample opportunities for exposure to varied food items. Essentially no information is available on hedgehogs’ specific nutrient requirements. They have a simple digestive tract, with no external distinction between small and
Sustainable Program Research, Novus International Inc., 20 Research Drive, St. Charles, MO 63304, USA E-mail address: [email protected] Vet Clin Exot Anim 12 (2009) 335–337 doi:10.1016/j.cvex.2009.01.006 vetexotic.theclinics.com 1094-9194/09/$ – see front matter ª 2009 Elsevier Inc. All rights reserved.
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large intestine and no cecum.7 Thus, they likely have limited ability to ferment plant cell wall constituents. Hedgehogs (at least Erinaceous europaeus) possess chitinase in their gastric mucosa and in their pancreas,7 suggesting that they are able to digest the chitinous exoskeletons of insects. A preliminary study of fiber digestion in A atelerix confirmed that 64% to 68% of dietary fiber added as chitin (specifically, crab shell chitin) was digested, as compared with only 38% when fiber was added as cellulose.8 Captive hedgehogs tend to become obese;2,6 thus, captive animals should be weighed regularly to monitor body condition. Obesity can lead to inactivity, metabolic changes, and other health issues. To combat this tendency toward obesity, because it is poorly digested, cellulose (plant matter) may be added to hedgehog diets to dilute nutrient density, thereby reducing overall dietary calories.8 Hepatic lipidosis, which may be related to obesity, a high-fat diet, or too rapid weight loss, has been documented in African hedgehogs.2 Therefore, weight-reduction diets containing not only decreased amounts of food but lower fat and caloric concentrations should be implemented gradually. Specific nutritional problems, including taurine-deficiency cardiomyopathies or retinopathies and fatty acid insufficiencies, reported in obligate carnivores have not been reported in hedgehogs. The lack of these nutritional problems, in addition to hedgehogs’ ability to utilize some dietary carbohydrates, suggests that hedgehog dietary requirements may be more similar to those of canids than of felids. CAPTIVE DIETARY HUSBANDRY
Hedgehogs are easy to feed and are quite adaptable. As an example of diet flexibility, 300 to 700-g adult hedgehogs offered a canned feline diet (20–30 g) containing approximately 60% water were fed once daily during ad libitum intake feeding trials; leftover food always remained. Dry matter intake averaged 1.4% to 3% of body weight, or 3.5% to 7.5% of body weight on an as-fed basis; it did not vary by diet treatment, although dietary fiber concentration ranged from 3% to 27% of dry matter in that study.8 Thus, hedgehogs have been successfully maintained on a variety of moderately high-protein (30%–50%, dry matter basis) moderate-fat (10%–20%) diets, including canned and dry dog and cat foods; kitten foods; ferret foods; commercial products specific for hedgehogs; and dry and semimoist insectivore diets supplemented with earthworms, insects, and small quantities of chopped vegetable and fruit.2,6,8 Treats include supplemented meat mixtures, hard-boiled or scrambled eggs, pinky mice, and vegetable or meat jarred human baby foods.6 Dairy products, such as cottage cheese and milk, should be avoided, however, because of reports of lactose intolerance.9 Insects offered should be from healthy colonies, fed gut-loaded diets, or dusted with a calcium supplement before feeding to hedgehogs. Insect-only diets are not recommended because of the potential for nutritional imbalances and to duplicate natural omnivorous feeding habits better.2 Dry foods or uncooked produce is suggested over soft dietary ingredients to maintain tooth and gum health. Fresh water should be provided ad libitum in a shallow dish; animals can also learn to drink from sipper bottles. PREGANCY, LACTATION, AND HAND-REARING CONSIDERATIONS
Female hedgehogs that gain more than 50 g within 3 weeks after cohabiting with a male hedgehog are usually pregnant and should be isolated. Increased amounts of food can be offered during the 34- to 37-day gestation period and throughout lactation (4–6 weeks), with no need to alter dietary nutrient concentration.2 Should
Hedgehog Feeding and Nutrition
supplemental feeding be required for young (termed hoglets or urchins), goat’s milk and Esbilac (Pet Ag., Inc., Hampshire, Illinois) have been fed successfully.10,11 An oral rehydration fluid, such as Pedialyte (Abbott Nutrition, Columbus, Ohio), is recommended initially, with consecutive feedings gradually decreasing rehydration fluid/ formula concentrations.10 Colostrum (preferably from goats, taken during the first 48 hours after kidding) should be added to hand-rearing formulas for at least 21 days (days 1 and 2, 50:50 colostrum/milk; next 21 days, 25:75 colostrum/milk).11 Young can be fed with a plastic pipette or a 1-mL syringe fitted with a blunted 16gauge needle covered with small-bore rubber tubing to be used as a teat. As with other species, weaning to an adult diet can be accomplished by gradually mixing a softened or blended solid diet into formula. Hand-reared hedgehogs should gain a minimum of 1.5 g/d but not more than 6 to 7 g/d when fully weaned.10
AREAS FOR FURTHER INVESTIGATION
1. Hedgehogs seem to be truly omnivorous. Studies still need to confirm that canid, rather than felid, digestive physiology underlies nutritional principles in captive feeding of hedgehogs, however. 2. Studies of the need for dietary taurine for protein metabolism, the role of d-6 desaturase activity in fatty acid metabolism, and the ability to synthesize vitamin A from dietary carotenoids would improve our understanding of hedgehog nutritional physiology and might contribute to more optimal captive diet development. 3. Further investigation of dietary fiber nutrition in hedgehogs could be important in developing targeted life-stage or clinical diets for the species. REFERENCES
1. Walker EP. Insectivora. In: Mammals of the world. Baltimore (MD): Johns Hopkins University Press; 1975. p. 103–79. 2. Larson RS, Carpenter JW. Husbandry and medical management of African hedgehogs. Vet Med 1999;94(10):877–88. 3. Reeve N. Hedgehogs. London: Poyser Natural History; 1994. 4. Merrit DA Jr. Husbandry, reproduction and behaviour of the West African hedgehog. Intern Zoo Yearbk 1981;21:128–31. 5. Okaeme AN, Oeakwe ME. Gastrointestinal helminthes and food of the African hedgehog Atelerix albiventris (Wagna) in the Kainji Lake area of Nigeria. Afr J Ecol 1988;26:239–41. 6. Smith AJ. Husbandry and medicine of African hedgehogs (Atelerix albiventris). J Small Exotic Anim Med 1992;2:21–8. 7. Stevens CE. The mammalian digestive tract. In: Comparative physiology of the vertebrate digestive system. Cambridge (UK): Cambridge University Press; 1990. p. 40–85. 8. Graffam WS, Fitzpatrick MP, Dierenfeld ES. Fiber digestion in the African whitebellied hedgehog (Atelerix albiventris): a preliminary evaluation. J Nutr 1998; 128:2671S–3S. 9. Stocker L. The St. Tiggywinkles hedgehog fact sheet. Haddenham (UK): The Wildlife Hospital Trust; 2003. p. 1–19. 10. Robinson I. Hedgehogs. In: Gage LJ, editor. Hand-rearing wild and domestic mammals. Ames (IA): Iowa State Press; 2002. p. 75–80. 11. Stocker L. Artificial rearing of orphaned hedgehogs. Haddenham (UK): The Wildlife Hospital Trust; 2003. p. 1–9.
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At least four genera and 14 species of hedgehogs are widespread throughout Europe, Russia, China, and Africa. Adult hedgehogs weigh 400 to 1100 g.1 African pygmy hedgehogs, Atelerix albiventris, are distributed from the southern Sahara through Central and East Africa. Weighing 250 to 700 g, pygmy hedgehogs are popular exotic pets in North America. Hedgehogs are found in a variety of habitats, including deserts, steppes, and forests. They dig burrows; seek shelter under brush piles, logs, rocks, tree roots, and buildings; and need hiding places and nesting materials in captivity. European species hibernate during the coldest months of the year; African hedgehogs typically do not hibernate, but they can hibernate in cool environments.2 Hibernation, however, is not recommended for captive hedgehogs, because the decrease in metabolism leaves them more susceptible to infection; thus, animals should be maintained at temperatures higher than 18 C.2 GENERAL FEEDING BEHAVIORS AND DIGESTIVE PHYSIOLOGY
Although classified as members of the order Insectivora, hedgehogs are quite omnivorous, eating a variety of invertebrates (eg, beetles, millipedes, worms, slugs, snails) in addition to small vertebrate prey (eg, frogs, snakes, lizards, eggs, young birds, mice) and plants.1,3 Limited general information published on the dietary habits of African hedgehogs4–6 suggests that they are also opportunistic omnivores, consuming a more varied diet based on food availability. Hedgehogs are nocturnal, starting to feed at dusk. Because they are good swimmers and active climbers, they have ample opportunities for exposure to varied food items. Essentially no information is available on hedgehogs’ specific nutrient requirements. They have a simple digestive tract, with no external distinction between small and
Sustainable Program Research, Novus International Inc., 20 Research Drive, St. Charles, MO 63304, USA E-mail address: [email protected] Vet Clin Exot Anim 12 (2009) 335–337 doi:10.1016/j.cvex.2009.01.006 vetexotic.theclinics.com 1094-9194/09/$ – see front matter ª 2009 Elsevier Inc. All rights reserved.
336
Dierenfeld
large intestine and no cecum.7 Thus, they likely have limited ability to ferment plant cell wall constituents. Hedgehogs (at least Erinaceous europaeus) possess chitinase in their gastric mucosa and in their pancreas,7 suggesting that they are able to digest the chitinous exoskeletons of insects. A preliminary study of fiber digestion in A atelerix confirmed that 64% to 68% of dietary fiber added as chitin (specifically, crab shell chitin) was digested, as compared with only 38% when fiber was added as cellulose.8 Captive hedgehogs tend to become obese;2,6 thus, captive animals should be weighed regularly to monitor body condition. Obesity can lead to inactivity, metabolic changes, and other health issues. To combat this tendency toward obesity, because it is poorly digested, cellulose (plant matter) may be added to hedgehog diets to dilute nutrient density, thereby reducing overall dietary calories.8 Hepatic lipidosis, which may be related to obesity, a high-fat diet, or too rapid weight loss, has been documented in African hedgehogs.2 Therefore, weight-reduction diets containing not only decreased amounts of food but lower fat and caloric concentrations should be implemented gradually. Specific nutritional problems, including taurine-deficiency cardiomyopathies or retinopathies and fatty acid insufficiencies, reported in obligate carnivores have not been reported in hedgehogs. The lack of these nutritional problems, in addition to hedgehogs’ ability to utilize some dietary carbohydrates, suggests that hedgehog dietary requirements may be more similar to those of canids than of felids. CAPTIVE DIETARY HUSBANDRY
Hedgehogs are easy to feed and are quite adaptable. As an example of diet flexibility, 300 to 700-g adult hedgehogs offered a canned feline diet (20–30 g) containing approximately 60% water were fed once daily during ad libitum intake feeding trials; leftover food always remained. Dry matter intake averaged 1.4% to 3% of body weight, or 3.5% to 7.5% of body weight on an as-fed basis; it did not vary by diet treatment, although dietary fiber concentration ranged from 3% to 27% of dry matter in that study.8 Thus, hedgehogs have been successfully maintained on a variety of moderately high-protein (30%–50%, dry matter basis) moderate-fat (10%–20%) diets, including canned and dry dog and cat foods; kitten foods; ferret foods; commercial products specific for hedgehogs; and dry and semimoist insectivore diets supplemented with earthworms, insects, and small quantities of chopped vegetable and fruit.2,6,8 Treats include supplemented meat mixtures, hard-boiled or scrambled eggs, pinky mice, and vegetable or meat jarred human baby foods.6 Dairy products, such as cottage cheese and milk, should be avoided, however, because of reports of lactose intolerance.9 Insects offered should be from healthy colonies, fed gut-loaded diets, or dusted with a calcium supplement before feeding to hedgehogs. Insect-only diets are not recommended because of the potential for nutritional imbalances and to duplicate natural omnivorous feeding habits better.2 Dry foods or uncooked produce is suggested over soft dietary ingredients to maintain tooth and gum health. Fresh water should be provided ad libitum in a shallow dish; animals can also learn to drink from sipper bottles. PREGANCY, LACTATION, AND HAND-REARING CONSIDERATIONS
Female hedgehogs that gain more than 50 g within 3 weeks after cohabiting with a male hedgehog are usually pregnant and should be isolated. Increased amounts of food can be offered during the 34- to 37-day gestation period and throughout lactation (4–6 weeks), with no need to alter dietary nutrient concentration.2 Should
Hedgehog Feeding and Nutrition
supplemental feeding be required for young (termed hoglets or urchins), goat’s milk and Esbilac (Pet Ag., Inc., Hampshire, Illinois) have been fed successfully.10,11 An oral rehydration fluid, such as Pedialyte (Abbott Nutrition, Columbus, Ohio), is recommended initially, with consecutive feedings gradually decreasing rehydration fluid/ formula concentrations.10 Colostrum (preferably from goats, taken during the first 48 hours after kidding) should be added to hand-rearing formulas for at least 21 days (days 1 and 2, 50:50 colostrum/milk; next 21 days, 25:75 colostrum/milk).11 Young can be fed with a plastic pipette or a 1-mL syringe fitted with a blunted 16gauge needle covered with small-bore rubber tubing to be used as a teat. As with other species, weaning to an adult diet can be accomplished by gradually mixing a softened or blended solid diet into formula. Hand-reared hedgehogs should gain a minimum of 1.5 g/d but not more than 6 to 7 g/d when fully weaned.10
AREAS FOR FURTHER INVESTIGATION
1. Hedgehogs seem to be truly omnivorous. Studies still need to confirm that canid, rather than felid, digestive physiology underlies nutritional principles in captive feeding of hedgehogs, however. 2. Studies of the need for dietary taurine for protein metabolism, the role of d-6 desaturase activity in fatty acid metabolism, and the ability to synthesize vitamin A from dietary carotenoids would improve our understanding of hedgehog nutritional physiology and might contribute to more optimal captive diet development. 3. Further investigation of dietary fiber nutrition in hedgehogs could be important in developing targeted life-stage or clinical diets for the species. REFERENCES
1. Walker EP. Insectivora. In: Mammals of the world. Baltimore (MD): Johns Hopkins University Press; 1975. p. 103–79. 2. Larson RS, Carpenter JW. Husbandry and medical management of African hedgehogs. Vet Med 1999;94(10):877–88. 3. Reeve N. Hedgehogs. London: Poyser Natural History; 1994. 4. Merrit DA Jr. Husbandry, reproduction and behaviour of the West African hedgehog. Intern Zoo Yearbk 1981;21:128–31. 5. Okaeme AN, Oeakwe ME. Gastrointestinal helminthes and food of the African hedgehog Atelerix albiventris (Wagna) in the Kainji Lake area of Nigeria. Afr J Ecol 1988;26:239–41. 6. Smith AJ. Husbandry and medicine of African hedgehogs (Atelerix albiventris). J Small Exotic Anim Med 1992;2:21–8. 7. Stevens CE. The mammalian digestive tract. In: Comparative physiology of the vertebrate digestive system. Cambridge (UK): Cambridge University Press; 1990. p. 40–85. 8. Graffam WS, Fitzpatrick MP, Dierenfeld ES. Fiber digestion in the African whitebellied hedgehog (Atelerix albiventris): a preliminary evaluation. J Nutr 1998; 128:2671S–3S. 9. Stocker L. The St. Tiggywinkles hedgehog fact sheet. Haddenham (UK): The Wildlife Hospital Trust; 2003. p. 1–19. 10. Robinson I. Hedgehogs. In: Gage LJ, editor. Hand-rearing wild and domestic mammals. Ames (IA): Iowa State Press; 2002. p. 75–80. 11. Stocker L. Artificial rearing of orphaned hedgehogs. Haddenham (UK): The Wildlife Hospital Trust; 2003. p. 1–9.
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