carotenoid supplementation/gut loading

[furcifer5]

I was wondering if anyone on this forum has experience with carotenoid supplementation in the gut loading of feeder insects. The effects on general health and fertility of (some species of) tree frogs and dendrobatids seem to be very interesting:

Some reading:
http://www.eaza.net/activities/Docum...tionIssue5.pdf
Carotenoid supplementation enhances reproductive success in captive strawberry poison frogs (Oophaga pumilio) - Dugas - 2013 - Zoo Biology - Wiley Online Library

[JeffreH]

I'll admit, I didn't read the full Dugas et. al but have it saved to Mendeley when I have more time. Looks like some good literature, thank you for sharing! = )

I had a very brief discussion with Mark Finke about carotenoid supplementation for insects (some of the research behind Timberline's Vita-Bugs). I know they have potentially important functions in insects, we know they are beneficial to our health... so it is not that surprising that there are benefits to amphibians as well.

Carotenoids are typically obtained from eating plant matter, and insectivores may obtain most of their carotenoids indirectly by feeding on herbivorous insects. Some carotenoids with naturally high vitamin A activity can be obtained by insectivores feeding on insects with compound eyes... Most larval insects only have simple eyes, but adult flies and the like manifest high concentrations of carotenoids in their eyes (having roles in reproductive pathways and presumably to help protect the eyes from ultraviolet light damage).

Another potential benefit of carotenoids might be in reproductive fitness of feeder colonies. I have a bit of a hypothesis that cockroach reproduction might be increased with carotenoid supplementation. There is speculation that things like oranges increase their reproductive success, but it seems that many of the orange-colored, beta-carotene containing foods are eagerly accepted by them. Therefore, supplementing the diet of your feeders with carotene containing foods may have both direct benefits on the feeder insect itself and indirect benefits on the herp consuming it.

[Heatheranne]

The supplementation in frogs is said to aid in reproduction/fertilization, especially in dart frog species.

I too will read the articles, probably tomorrow. Thanks for sharing!

[bugguy]

Hi All,

Mark Finke here. As Jeff mentioned I'm the person that provides technical support for Timberlines "Vita-bugs" which among other nutrients also has enhanced levels of carotenoids (mostly beta-carotene but also some lutein). In addition to some carotenoids serving as a source of vitamin A they seem to be involved in a variety of other functions including coloration, immune response ad reproduction. I did exchange e-mails with the author of the article mentioned above and she confirmed they did not see enhanced coloration in their frogs. Both Ogilvey and Brenes Soto also saw benefits to carotenoid supplementation although in the Ogilvy article the tadpole (not he adult) diet was supplemented. Also Oonincx has shown that feeding locusts carrots enhanced their carotenoid content although some (but probably not all) of that enhancement was "gut-loading" with the rest being incorporated into the tissue of the insect. Currently I am working on trying to quantify carotenoids in wild insects as a model or what we should be doing for commercially raised insects.

If I can answer any questions please let me know.

Ogilvy et al 2012. A brighter future for frogs? The influence of carotenoids on the health, development and reproductive success of the red-eye tree frog. Animal Conservation 15:480-488.
Brenes Soto, A. and E. Dierenfeld. 2012. Effect of dietary carotenoids on skin pigmentation in tomato frogs (Dyscophys guineti). European Nutrition Research Group Proc., Zurich, Switzerland.
Oonincx D.G.A.B., van der Poel A.F.B. 2010. Effects of diet on the chemical composition of migratory locusts (Locusta migratoria). Zoo.Biol. 28:1-8.