Vitamins naturally

[Dartfrogfreak]

I thought this might make an interesting topic.

Just wondering anyone knows how dart frogs & other reptiles & Amphibians get there calcium & other vitamins in the wild.



TODD

I would guess that they go to thier local pharmacy and buy vitamin supplements like the rest of us.

[jbates]

*groan* That was awful!

Seriously, I'd imagine they get most of their vitamins from the gut contents of the insects they eat.

[Ed]

There is some indication that in reptiles (at least for lizards) and amphibians there is some selection based on the nutrient content of the food item. Typically calcium is obtained by feeding on soil dwelling arthropods as many soils contain calcium. When ingesting soil dwelling arthropods, there is often soil in the digestive tract as well as soil particles sticking to the insect and occasionally the tongue as part of the capture attempt. Some arthropods such as isopods are known to have calcium rich exoskeletons.
D3 is typically the result of the photoconversion of provitamin D into D3. In chelonians, exposure to three months of unfiltered sunlight can allow the tortoise to synthesize enough D3 to last the animal the entire year.

Most of the dietary needs will be contained in the tissues and gut contents of the invertebrates that they are consuming.

One of the reasons we may see more issues in the captive populations than is seen in the wild is because we are feeding high calorie prey items, which can be driving growth and reproductive metabolism at significantly higher rates/levels than what would be seen in the wild. This increase in metabolic rates is going to increase the metabolic demand for vitamins and minerals at the same time.

Ed

[Dartfrogfreak]

so would it be possible to produce this in our vivs?

[Ed]

Hypothetically maybe, in practice with the typical vivaria for the hobby, no.

You would need to be able to balance the palatabilty of the available invertbrate community in an enclosure with the required dietary needs of the frogs. In addition you would need to balance the provitamin A/vitamin A availability of the plants to the insects consuming the plants to the rate of consumption of the insects.
In very large greenhouses (like at NAIB) there are typically a wide enough variety of plants as well as invertebrates to meet the needs of the frogs but even then there are really only good populations in a couple of locations.
In the cages of the size typically seen in the hobby, the best you can really do is get a good invert population that would supplement some of the diet of the frogs but it can take a number of years for the invertebrate populations to stabalize enough for this to happen. (Check the frognet and dendroboard discussions on this with Brent Brock in the frognet archives and here on dendroboard).

Ed