The effects of preformed vitamin A and provitamin A carotenoid supplementation on tadpoles of the poison frog Phyllobates vittatus

This is a Preprint and has not been peer reviewed. The published version of this Preprint is available: This is version 5 of this Preprint.

Add a Comment

You must log in to post a comment.


There are no comments or no comments have been made public for this article.


Download Preprint


Roberto Marquez, Rachel Arkin


Understanding the nutritional requirements of captive animals is necessary for proper animal husbandry, however, the specific dietary requirements for many amphibian species commonly kept in captivity are unknown. Like most vertebrates, frogs cannot synthesize carotenoids and must therefore obtain these essential nutrients through diet. It is unclear if amphibians can cleave provitamin A carotenoids to form vitamin A metabolically within the body, so common practice is to supplement their captive diets with both preformed vitamin A and provitamin A carotenoids. We carried out a feeding experiment in tadpoles of Phyllobates vittatus, a commonly kept poison frog species, to test the effects of supplementing a fish flake diet with a provitamin A carotenoid (2.5mg/g β-carotene) and vitamin A ( 0.033-0.066µg/ml retinyl acetate), both individually and in combination. Contrary to our expectations, supplementation had either no effect or adverse effects on tadpole growth and survivorship. Tadpoles reared under supplemented diets with vitamin A showed higher mortality rates, coupled with symptoms of hypervitaminosis A. Survivors had a smaller body size and mass at metamorphosis. β-carotene supplementation alone had no detectable effect. The vitamin A and β-carotene levels in our supplemented diet have been shown to be harmless or benefit tadpoles of other species, yet our results indicate that adding these amounts to what is found in a generalist fish flake mix can have detrimental effects on P. vittatus tadpoles. More broadly, this study highlights the importance of creating husbandry guidelines based on the specific physiological needs of the species (or species groups) being kept in captivity, rather than general ones for all amphibians, as is often done.



Biology, Life Sciences, Veterinary Medicine, Zoology



Published: 2023-02-27 17:26

Last Updated: 2024-01-30 01:20

Older Versions

CC-By Attribution-NonCommercial-NoDerivatives 4.0 International

Additional Metadata

Conflict of interest statement:
The Authors declare no conflict of interest.