Studbook nr. 5, December 2008

EUROPEAN STUDBOOK CROWNED PIGEONS
5.3 Nutrition
One of the explanations for the slow natural growth of the population of crowned pigeons in
captivity might be a difference between nutrition of crowned pigeons in captivity and in the wild.
Therefore, in 1995, Anneke Hallebeek, who is now working at the University of Utrecht, compared
the nutrition of a lot of European zoos (Hallebeek, 1995). In 1997, a research project was carried
out in Papua New Guinea by Marc Damen to study the ecology of crowned pigeons in the wild. He
also sampled some crop and stomach contents from crowned pigeons for analysing. More
information about this subject can be found in the previous numbers of the European Studbook of
Crowned Pigeons.
Literature
Because of their size and ecology and because there are only a few notes about feeding in the wild,
the diet of turkeys is used as a guideline to determine the need of crowned pigeons. According to
Robbins from the University of San Diego, the daily need for energy for non-migratory nonproductive
birds in general, kept under a temperature of 25 degrees Celsius is 330.1xG 0.75 (Klasing,
1998), which should mean for a mature crowned pigeon of 2.5 kg a total of 2,7 MJ metabolizable
energy per day (Griminger, 1983). The need for protein based on data for non-productive laying
hens and turkeys should be approximately 25 grams per day and of course higher in the
reproductive season (National Research Institute, 1984). Because of the short caeca of crowned
pigeons, the vitamin B synthesis might be insufficient and therefore in comparison with poultry the
food has to be supplemented with at least vitamin B 6 and B 12 (Hallebeek, 1995). Some institutions
also add vitamin C, because it became evident that birds, when stressed, are unable to produce
enough vitamin C (Van Gennip, 1988). Research showed that birds, which are being kept indoors,
have a higher demand for vitamins (National Research Institute, 1984).
Practice in zoos and birdparks
In 1995 a questionnaire was sent out to all participants in the crowned pigeon EEP. Apart from
questions about nutrition, a lot of other factors were studied, like the size of the enclosure, other
species kept in the same enclosure, number and sex ratio of the crowned pigeons in the enclosure
and of course breeding results, because the aim of the questionnaire was to determine an optimal
diet for crowned pigeons. The following data have been derived from the results from the
questionnaires.
The daily need for energy seems to be 1.5 MJ metabolizable energy per day. Because 55-60% of
the gross energy should be metabolizable, the gross energy intake should be 2.5 MJ per day. The
average food intake of adult crowned pigeons is about 250 grams with 40% dry matter. The best
results were achieved in institutions that supply the crowned pigeons with a diet consisting of 9-11
g crude protein per MJ metabolizable energy for maintenance (approx. 15 grams per day) and 11-
14 grams for production (20 grams per day) (Hallebeek, 1995).
Especially the ratio of calcium was low: the German researcher Meyer advised a need for
calcium for maintenance for pigeons of 0.8 grams per MJ metabolizable energy, which means
about 1.2 grams calcium per day for a bird of 2.5 kg. Most diets for crowned pigeons only contain
less than 0.5 gram of calcium per day, but it might be possible that some zoos feed their pigeons
additional mineral stones or lime stones or oyster shells and did not list this on the questionnaire. A
deficiency of calcium causes a decalcification of the skeleton. Of course it is simple to add some
mineral stones to the food. Calcium can only be converted if a sufficient amount of vitamin D is
supplied. In most cases less than 74 International Units vitamin D per MJ metabolizable energy is
supplied. As a result of this the Ca : P ratio in most diets is not that good (Hallebeek, 1995).
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