Applications 16-20


Marcus Clauss MSc1,2, Edmund Flach2, Keb Ghebremeskel BSc, MSc, PhD3, Jean-Michel Hatt
Dr.MSc 4, and Cliff Tack2
1 Institute for Zoo Biology and Wildlife Research Berlin, PF 601103, D-10252 Berlin, Germany, 2
Veterinary Science Group, Institute of Zoology and Whipsnade Wild Animal Park, Dunstable, Beds., LU6 2LF, United Kingdom, 3 Institute of Brain Chemistry and Human Nutrition, University of North London, Holloway Rd., London N7 8DB, United Kingdom, 4 Division of Zoo Animals and Exotic Pets, Veterinary Faculty, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland

Captive giraffe (Giraffa camelopardis) are known to be, in comparison with free-ranging individuals, deficient in linolenic acid. There is no clear evidence whether this reflects merely a different diet, or whether it will also impair body functions. However, large numbers of captive giraffe have died with no obvious necropsy results except for serous atrophy of body fat (per acute mortality syndrome of giraffe). A deficiency in linolenic acid could, in theory, make animals more susceptible to factors triggering fat mobilisation, and worsen its effects. Therefore, supplementation with linolenic acid could be understood as part of a prophylactic program against the peracute mortality syndrome. As linseed contains significant amounts of linolenic acid, the feeding of linseed extraction chips might be a practical way of supplementation. Captive giraffe with low linolenic acid status in their blood lipids were introduced to a diet that included linseed extraction chips. Blood lipids, of animals from which samples were available after the change in dietary regime (n=2), showed an increase in linolenic acid content. One of the animals had a history of skin lesions resistant to treatment. The skin lesions improved markedly during the course of linseed supplementation. While the long-term effects of either linolenic acid deficiency and linolenic acid supplementation in giraffe remain to be demonstrated, these results suggest that giraffe might benefit from the addition of linseed extraction chips to their diet.


Kristin Leus PhD1
1 Royal Zoological Society of Antwerp, Koningin Astridplein 26, 2018 Antwerp, Belgium

This paper reviews the available information on stomach anatomy, digestion, foraging behaviour and diet of wild and captive babirusa, in order to formulate a recommended diet for babirusa in zoological gardens. Although unilocular, the babirusa stomach contains an enlarged area of mucus-producing cardiac glands (>70% of internal surface area v. 30% in Sus scrofa) with a near-neutral pH and populations of microorganisms. The true gastric glands are confined to a small gastric unit. Results from two independent digestibility studies on captive babirusa were in concordance with the general characteristics of non-ruminant forestomach fermenting frugivore/concentrate selectors specialised in the fermentation of more easily digestible plant components. Passage time experiments suggested that no part of the digestive tract selectively held digesta longer than any other part and that caecocolic fermentation may be less important in the babirusa than in the Eurasian wild pig. Behavioural observations on wild and captive babirusa indicated that they usually practise surface foraging, that rooting only takes place in loose soil, that they stand on their hind legs to reach food in higher places and that males tend to monopolise food when animals are fed together. Published information as well as a recent field study suggest that wild babirusa show a marked preference for fruit and also consume a fair amount of animal material as well as mineral-rich soil and water. Analyses of the dietary habits of babirusa in 25 zoos worldwide revealed food preferences similar to those of wild animals. However, calculation of the nutritional composition of the captive diets revealed a spread in values so large that it is impossible for all of these diets to answer to the nutritional requirements of the species. Using the above information, adapted prediction equations and the animal nutritionist program a recommended diet for babirusa in captivity will be formulated.


Nico J. Schoemaker DVM1
1 Division of Avian and Exotic Animal Medicine and Surgery, Department of Clinical Sciences and Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 8, 3584 CM Utrecht, The Netherlands

Tracing and correcting diet related problems in (companion) birds are one of the major tasks of an avian veterinarian. Diseases that, in part, are due to an excess or deficiency of one nutrient are: hypovitaminosis A, hypocalcaemia in African grey parrots (Psittacus erithacus), goitre in budgerigars and iron storage disease in mynah birds and toucans. Hypovitaminosis A will lead to a metaplasia of the mucus membranes, which can lead to chronic rhinitis and respiratory fungal infections. Seed-based diets are deficient in up to 20 nutrients. Calcium is one of those nutrients and if a seedbased diet is not supplemented with a calcium source like grit this will lead to a secondary nutritional hyperparathyroidism. In African grey and timneh parrots a specific syndrome is known to cause tetanic convulsions due to a severe hypocalcaemia. Over supplementation of the diet with vitamin D can cause an intoxication of which the initial symptoms are polyuria and polydipsia. The precise aetiology of iron storage disease in mynah birds and toucans is not fully understood. A low iron and low vitamin C diet are recommended for treatment. An iodine deficiency, leading to goitre, is most commonly seen in budgerigars that are fed an all-seed diet containing a lot of millet seeds. Conditions that can be caused by a multi-deficient and / or poorly balanced diet are reproductive disorders, poor feather quality and decreased immunity leading to secondary infections. Besides treating the underlying infection these patients should be switch over to a commercial, extruded avian diet. Although, obesity is not considered as a disease by many people, it must be considered a problem. Galahs, Amazon parrots and budgerigars are especially prone to obesity, which can lead to hepatolipidosis and lipoma. Therefore, it is advised to let these birds gradually loose weight.


Marc Damen Ir.1
1 Wageningen University and Rotterdam Zoo, 3000 AM Rotterdam, The Netherlands

Crowned pigeons (Goura sp.) suffer from a negative natural growth of the population in captivity. One of the explanations might be a difference between nutrition of crowned pigeons in captivity and in the wild. In 1995 a questionnaire was sent out to all participants in the European Endangered Species Program for crowned pigeons. An average in nutrients of the five institutions with the best reproductive results was calculated. In 1997 the crop and stomach contents of four crowned pigeons who were shot in Papua New Guinea could be analysed at Research Institute ‘De Schothorst’at Lelystad, the Netherlands. In table 1 the results of both investigations are summarised.

Table 1. Comparison between crowned pigeon food in the wild and in captivity Zoo-diet
(g/kg dry matter)
n=5 institutions
Wild-diet * (g/kg dry matter)
n=4 pigeons
Crude protein 150 ± 38 96 ± 12
Crude fat 110 ± 16 102 ± 24
Crude fibre 110 ± 21 449 ± 73
Crude ash 120 ± 30
Phosphorus 2.0 ± 0.8 1.1 ± 0.2
Calcium 4.0 ± 1.7 2.9 ± 0.7
*values from samples taken from the crop

In captivity sometimes the ad libitum available mineral stones could have been omitted, there might be other animals in the enclosure as well and seasonal changes in the diet have been omitted. In the data from the crowned pigeons collected from the wild it is also not possible to see seasonal influences, and there were only very few data available. The most remarkable difference between the diets is the ratio of crude fibre, which is four times as high in the wild as in captivity. The crop and stomach of crowned pigeons in the wild contained a lot of large seeds up to 6 cm long, while in captivity they are only being fed small food parts. It should be considered to supply the crowned pigeons with larger food parts. Almost nothing is known about the gastro-intestinal tract of crowned pigeons and it might be useful to conduct research into this topic to determine their nutritional needs. The variation in the diets of the different institutions seems not to have any visible effect on the birds. Of course there are more factors who can influence reproductive results, like zoo-technical factors, behaviour and stress.


Pavlina Hajkova MVDr1 and Karel Pithart RNDr2
1 University of Veterinary and Pharmaceutical Sciences Brno, Faculty of Veterinary Medicine, Small Animal Clinic, Exotic Animal Division, 2 Curator of the Birds, Zoological Garden Prague, Czech Republic

In summer 1997 it became necessary to hand-raise four pheasant pigeons (Otidiphaps nobilis nobilis) squabs. In all cases the breeding pair left the nest. The eggs were artificially incubated. Length of the incubation was 35, 31, and in two cases 29 days. There was no opportunity to obtain a commercial squab diet. Therefore we had to create a diet with basic nutrient content similar to the pigeon crop ilk (PCM). Based on literature we estimated that PCM contains approximately 74-77% water, 11-13% protein, 5-9% lipids, and 1,2-1,8% carbohydrates. The main problem was to keep a relatively low level of carbohydrates. We therefore prepared three different formulas: 1) Egg yolk (fresh or boiled) and fat free-cottage cheese 1:1, calcium and vitamin B supplement. Content: 65-66% water, 15-20% protein, 13-16% lipids, 2,2-2,5% carbohydrates, and 300-350 mg Ca/ 100g. 2) Egg yolk (fresh or boiled), Canine Milk Substitution Instant« (Waltham Veterinary Services, united Kingdom), Feline Concentration Instant Diet« (Waltham Veterinary Services, United Kingdom) and water 4:1:1:2, calcium and vitamin B supplement, unsaturaturated fatty acid supplement (Sangrim AV sol. ®), and probiotics (Avibion plv. ad us. vet. ®, Bioveta, Ivanovice na Hane, CR) Content: 54.4% water, 17.5% protein, 23% lipids, 4,5% carbohydrates, and 300-350 mg Ca/100 g. 3) Egg yolk (fresh or boiled), Canine Milk Substitution Instant« (Waltham Veterinary Services, United Kingdom), Feline Concentration Instant Diet« (Waltham Veterinary services, United Kingdom), water, fat free cottage-cheese and row egg white 4:1:1:2:2:2, calcium and vitamin B supplement, unsaturated fatty acid supplement (Sangrim®), and probiotics (Avibion plv. ad us. vet. ®, Bioveta, Ivanovice na Hane, CR) Content: 68-71% water, 16-18% protein, 12-13% lipids, 1% carbohydrates, and 300-350 mg Ca/ 100 g. The first squab was fed formula No.1. This diet was higher in dry matter than the PCM, however, the ratio of nutrients was correct. Dilution with water made the diet too fluid and difficult to handle. The squab died on day 10 because of Pseudomonas aeruginosa infection. It showed good viability and crop emptying but low weight gain. The second squab was fed formula No.2, diluted with water depending on the clinical status of the bird. The bird died on day 4, after a recurrent gas dilatation of the crop. No yeast was found at laboratory examination; the cause of death was dysbacteriosis. The third squab, fed formula No. 3, died at 5 days of age and showed the same symptoms as the previous one. In this bird, moreover, bacterial pneumonia was diagnosed. The last, fourth, squab was fed formula 2 on day 1, and formula No. 1 on days 2 and 3. It had problems with gas dilatation of the crop from the first day. Dysbacteriosis and consequent overgrowth of toxinogenic bacteria was shown in the GIT. This squab died at the age of three days. Four problems are pointed out: 1) ability to digest the mammalian milk protein by squabs 2) possibility to add enzymes, IgA and essential fatty acids into the diet 3) alternative source for preparation of hand-feeding formulas for squabs 4) efficiency versus harmfulness of probiotics