Reddening in our Ibises - Part 1: Review of carotenoids

Mar 20 2010

Reddening in some of our birds, it is currently a hotly debated topic with many aviculturists of ibises, flamingos, spoonbills and pelicans. On Ibisday 2007, we have already dealt with this topic extensively. We want to give you, on the basis of a number of articles, more information on this subject, in this way we give you the opportunity to become a critical judge on the usefulness of administering colours and the role they play.

This is the first part of this series of articles. These are the other parts:

We have tried to turn the scientific literature in a smoothly readable text. We think it is always nice when we get feedback on our articles, do not be afraid to state your experiences with us.

Part 1: Review of carotenoids

Carotenes are responsible for the beautiful colour of birds: red, orange, yellow and green. But carotenes also provide the general health, they act as anti-oxidant and stimulate immunity. Carotenes are particularly important in sexual selection. For example, females prefer couples with brightly coloured males. In other words, the more carotenes, the brighter the colour will be and the more females can attract a male.

There are approximately some 600 carotenes known both natural and synthetic. They are present as a pigment in plants. For plants it work as absorber of light in photosynthesis. Did you know that in the daily diet for your ibis carotenes are present: Spirulina, linseed, corn, shrimp, fish,… Carotenes are also as a colour to the human diet.

A diet rich in carotenes gives no guarantee to show the quantity. Parasitic infections such as coccidiosis prevent the absorption of the intestinal contents into the blood.

There is a competition between the intake of the fat-soluble vitamin a and canthaxantine. This could have an impact on the protective effect of certain anti-oxidants. canthaxantine is not converted into a vitamin, unlike ß-carotene. An overdose of canthaxantine is possible.

There are two groups of carotenes important for our ibis:

  • Carotenes
    • a-carotene
    • ß-carotene
    • Lycopene
  • Xanthophylls
    • Zeaxanthinea
    • Lutein
    • Canthaxantine

Carotene (E160 a)

Carotene (E160 a) belongs to the group of carotene. It is an orange dye that occurs in many vegetables such as carrots and sweet potato. Red palm oil and leaves of many plants contain carotene. There are two different forms: alpha-carotene and beta-carotene.

ß-carotene is a precursor to vitamin a (retinol) and is therefore also known as a pro. The ß-carotene molecules consists of two retinol molecules with the tail together. When this molecule is split, created a vitamin two molecules. ß-carotene can be stored in the liver.

This is very interesting to remember for the food which is given to our birds: ß-carotene can never been given too much. Also you know that your birds always have enough vitamin A inside.

Canthaxantine

Canthaxantine belongs to the group of xanthophylls. This material was previously extracted from feathers of flamingos and lobsters. Now from cantharelles or synthesized from ß-caroteen.

It is used in various types of feed to:

  • egg yolks in Orange Yellow colours (chicken)
  • in muscles redder colours (salmon)
  • the coloration of the bird feathers (ibis and flamingos) 

Substance is stored in birds in almost all tissues.

Text: Ben Lamberigts
Header photo: Valerie

Sources

  • Couteel, P., Roodkleuring van ibissen: Ibisdag Antwerpen, 29-10-2007
  • Roodkleuring zalm, (Z.D)., [WWW], http://www.food-info.net/nl/qa/qafp13.htm, consulted [02/2008]
  • Threskior, Buvens, B., Lamberigts, B., Coorevits, K., Bauwens, K., (2007), Ibisvoeding, Project Dierengezondheid, Hogeschool Gent, Departement Biowetenschappen en Landschapsarchitectuur; België.