posted 7 May 03

Vitamin A as retinol can cause many problems with frogs (and other animals) but as I understand it Vitamin A deficiencies can also be mistaken for Vitamin A toxicity (as an aside comment so people do not necessarily claim all these issues are due to too high a vitamin A content). Many of the better supplements no longer use retinol as the source of the vitamin A (or only use it as part of the supplement) due to the potential problems and are using betacarotene instead.

At least one of the symptoms you reported is classical for secondary hyperparathyroidism (muscle spasms or tremors) as the vitamin A competes with D3 for uptake and this can affect calcium metabolism, which can result in tremors or seizures.

As it never seems to hurt to repeat the information as we are always getting new readers the ideal ratio is 10 to 1 to .1 ratio of A to D3 to E.

On a quick guess as retinol is fat stored the metabolization of the fat stores for egg laying may have subjected the females to excess vitamin A causing the sex specific deaths you noted.

On the aside did your vet ever culture the frogs for mycobacterial infections as I have seen leg infectionc caused by M. marinum.

Ed Kowalski
South Jersey