vitamin A toxicity levels

[j156ghs]

I use a few "complete" prepared diet products for my Hermann's and ZooMed's Grasslands Tortoise pellets seem the best.

I note that all the products contain some form of Vitamin A that can accumulate in the body and become toxic (similar to Vitamin D). One company said the amounts are intended to supply the daily requirement so it should be OK.

Does anyone have experience/education on this topic? I know of one powdered vitamin/mineral mix that has beta carotene, which doesn't accumulate, but a small-animal veterenarian told me there's not enough studies on reptiles to know if they can all convert beta carotene to vitamin A as needed.

Are there any signs of vitamin A toxicity in a tortoise? I know with some lizards, too frequent sheddings are a symptom.

 

[tortadise]

Yes it's called hypo vitamintosis A. It takes quite a bit to cause it. Hence the food containing lots of vitamin A should be fed sparingly. Yellow squash and carrots are the main ones. I've never had any problems or signs of vitamintosis A before but have seen medical documented cases when I was getting my CVA at A&M. It's pretty rare. And to what I remember on the cases it was solely caused by diet. I believe the mineral and vitamin additives have such a small amount that it would take extremes and ignorance to overdose. But it is heard of people way overusing these supplements.

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Sorry my I phone rembered "hypovitaminosis" from another post. Overdose on vitamin a is hyper vitamintosis. Stupid auto correct.

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And it shows about the same as lizards. Thin skin, swollen eyes, the severe cases were bad raw open wounds and beak problems. Symptoms did have a large list though. Swollen eyes typically are the most common. It's pretty hard to diagnose because lack of vitamin A also shows swollen eyes.

 

[Madkins007]

Some dosage guidelines can be found at https://sites.google.com/site/tortoiselibrary/nutrition/guidelines-and-dosages

If I recall the notes correctly, hypervitamintosis occurs at dosages roughly 5 times the norm.

 

[j156ghs]

Common Omnivore Diseases
Common species: Uromastyx lizards, box turtles, Asian turtles, bearded dragons, some aquatic turtles.

Hypovitaminosis A: Hypovitaminosis A is a common presentation in box turtles and aquatic turtles. Vitamin A is essential in the health of the mucus membranes, which will show immediate pathological changes when faced with a shortage of vitamin A or beta carotene in the diet.

The mucous membranes will harden and thicken as a consequence of the deficiency. Swelling of the eyelids is a common presentation in turtles, and a "parrot beak" and/or aural abscesses in box turtles should make the clinician suspicious of a diet deficient in vitamin A or beta carotene.

Vitamin A/beta carotene supplementation can reverse the signs in most cases. I prefer the beta carotene supplementation because of the toxicity potential of concentrated vitamin A preparations.

Hypervitaminosis A: Hypervitaminiosis A is a true toxicity and is usually caused iatrogenicly by an overdose injection of concentrated vitamin A preparation by the veterinarian. Clinical signs mimic a dermal burn and include sloughing of the skin. Treatment resembles burn wound therapy, including antibiotics, addressing the open wound and administering parenteral fluid.

Injections with highly concentrated vitamin A (e.g. 500,000 IU/ml) should be avoided and this preparation given only orally. Aquasol A (by Astra) is a good alternative for injection because it contains only 50,000 IU/ml.

http://www.veterinarypracticenews.c...nutritional-related-diseases-in-reptiles.aspx

 

[tortadise]

Great response. This is why I get upset when DVM's try and inject vitamin A and diagnose common Upper respiratory Issues associated with depleted Vitamin A and give a shot of it. Its very dangerous to give SQ (subcutaneously) or IM (intramuscular) injections especially knowing the issue of Vitamin A is only depleted because of the immune system draining its supply in the tortoises body to fight the Infection, that can be remedied with husbandry techniques and or anti-biotic regimens in serious cases.

 

[acrantophis]

I have seen vitamin A deficiencies treated by unknowing vets with Baytryl!