Vitamin sequestering

[Ed]

I've been away for awhile digging into some obscure things and trying out some odd stuff but I've still been concentrating heavily on amphibian nutritions... Many hobbyists use various methods to increase the nutritional quality of the feeders used for the caudates and tend to hate to allow things to go to waste. As a result at least in other sections of the amphibian hobby, people often mix old supplements into foods and media used to rear or "gut load" feeders for thier caudates. The problem with this practice is that it can backfire and actually result in problems for the caudates if fed as a routine part of the diet. Many arthropods (fruit flies, isopods etc) do not uptake or utilize vitamin A (other than to form rhodopsin or it's analog), D3 (only used as a precursor for cholesterol), but do uptake and store vitamin E (tocopherols particularly alpha tocopherols). The arthrodpod in question can generally absorb and store tocopherols to hundreds of times the level of tocopherols in the diet (in some cases much higher). These levels can be high enough to disrupt the levels of vitamin A and D3 needed for regular metabolism resuling in conditional deficiencies. So in general do not mix old supplements into foods used to rear arthropods that are going to be a major source of food for the caudates.

See for example
Cooke, J.; Sang, J.H.; 1970; Utilization of sterols by by larvae of Drosophila melanogaster; J. Insect Physiol. 16: 801-812
Draper, Harold H.; Philbrick, Diana P.; Agarwal, Sanjiv; Meidiger, Roy; Phillips, John P.; 2000; Avid uptake of lineolic acid and vitamin E by Drosophila melanogaster; Nutrition Research 20(1):113-120

Some comments

Ed

 

[michael]

Thanks Ed. This is valuable info. It's nice to see you on the forum now and again.
Is their any problem with throwing old paprika in an earthworm bin?

 

[Ed]

Thanks Ed. This is valuable info. It's nice to see you on the forum now and again.
Is their any problem with throwing old paprika in an earthworm bin?

There isn't any problem with throwing old paprika in the worm bin however while paprika is frequently suggested for enhancing red coloration, the red carotenoids in paprika are poorly absorbed when compared to carotenoids like astaxanthin and canthaxanthin. Instead you are mainly supplying beta carotene to the consuming animals. This is why it does a poor job of sustaining or returning red coloration to the animals to which it is fed.

I didn't forget the forum.. I was mainly using anurans as a target species to try out various methods and got busy with a lot of things. Now I've got some interesting stuff to share.

Ed

 

[Ed]

I should add that in non-primates canthaxanthin is fairly non-toxic and only in very large amounts does it show some issues (mainly increasing cholesterol mobilization). In primates however it does bad things.. like forming crystals in the eyes so that has been a focus of a lot of the studies.

Ed

 

[smukkkas]

I'm going to add this link to the ones you might want to check out, too: EAT It does a nice job breaking down what exactly it is, what can cause it, how to deal with it, etc.