Eggshells for Calcium, plus a question or two

[jsheffield]

We get our eggs from a local organic farm, and I use the eggshells to supplement my torts' calcium. I administer the eggshells in two ways:

1. whole eggshells in the enclosures
2. powdered eggshells on their food

As with the cuttlebone, some of my tortoises ignore the eggshells, and some are more interested... this is why I add the powdered stuff to their food1-2 times a week.

It seems that there's no absolute consensus on calcium needs in tortoises, beyond that they need it; so my questions are:

• is 1-2 times enough (they all get a varied diet that includes Mazuri or Zoo-Med 1-2 times a week)?
• my Redfoot Darwin loves the eggshells... can she (I think) get too much calcium?

Darwin seems to love crunching up the whole eggshells, and although I haven't gone nuts with it to date, she seems capable of eating as many eggshells as I put in her enclosure... crunching them noisily while watching me write.

Thanks,

Jamie

 

[Madkins007]

1. Dosage: Tortoises should get about 1.8 to 3mg of calcium per kilogram of tortoise (Mader, Douglas R., DVM, ed. Reptile Medicine and Surgery. Saunders Elsevier, 2nd Edition 2006. 1,242 pages.) A 1lb tort should get about 60-100mg a day. Good luck getting that all measured out! Overdoses are possible, but not common.

2. Calcium supplements: These can be tricky. Most of the calcium in a supplement is simply carried out of the system in the feces and urine. Part of the problem is particle size- the cells can only accept really small particles, and most supplement particles are too big and do not stay in the system long enough to be broken down small enough. This is generally called bio-availability and a lot of supplements for torts and humans are not bio-available. (Note- you can do a basic test for bio-availability of calcium by dropping some in vinegar. The faster it TOTALLY dissolves, the more bio-available it is.

3. Always always always remember that balanced diets and proper cares are better than supplements. You NEED vitamin D to 'unlock' the cell so it can absorb the calcium, and calcium absorption blocks iron absorption. In a balanced diet, the tort gets what it needs and everything works out.

4. Eggshells: These are tricky. Lots of sources do not like them because they are usually full of heavy metals from the grit and such in the chicken's diet, and because it is REALLY hard for the tort to break the tough structure down enough to be bio-available, even crushed pretty good. But- if they eat it, what the heck. Go for it.

5. Cuttlebone: Most research suggests that cuttlebone is not real bio-available, so...

 

[jsheffield]

1. Dosage: Tortoises should get about 1.8 to 3mg of calcium per kilogram of tortoise (Mader, Douglas R., DVM, ed. Reptile Medicine and Surgery. Saunders Elsevier, 2nd Edition 2006. 1,242 pages.) A 1lb tort should get about 60-100mg a day. Good luck getting that all measured out! Overdoses are possible, but not common.

2. Calcium supplements: These can be tricky. Most of the calcium in a supplement is simply carried out of the system in the feces and urine. Part of the problem is particle size- the cells can only accept really small particles, and most supplement particles are too big and do not stay in the system long enough to be broken down small enough. This is generally called bio-availability and a lot of supplements for torts and humans are not bio-available. (Note- you can do a basic test for bio-availability of calcium by dropping some in vinegar. The faster it TOTALLY dissolves, the more bio-available it is.

3. Always always always remember that balanced diets and proper cares are better than supplements. You NEED vitamin D to 'unlock' the cell so it can absorb the calcium, and calcium absorption blocks iron absorption. In a balanced diet, the tort gets what it needs and everything works out.

4. Eggshells: These are tricky. Lots of sources do not like them because they are usually full of heavy metals from the grit and such in the chicken's diet, and because it is REALLY hard for the tort to break the tough structure down enough to be bio-available, even crushed pretty good. But- if they eat it, what the heck. Go for it.

5. Cuttlebone: Most research suggests that cuttlebone is not real bio-available, so...

Thanks for the great info!

J