1. Welcome! Are you interested in tortoises? If so, we invite you to join our community! Our community is the #1 place for tortoise keepers to talk online. Once you join you'll be able to post messages, upload pictures of your tortoise and enclosure, and discuss any tortoise topic with other tortoise keepers. Get started today!

oxalates

Discussion in 'Advanced Tortoise Topics' started by Kapidolo Farms, Jun 14, 2019.

Help Support Tortoise Forums by donating:

  1. Kapidolo Farms

    Kapidolo Farms Well-Known Member 5 Year Member Platinum Tortoise Club Tortoise Club

    Joined:
    Nov 7, 2012
    Messages:
    4,621
    Likes Received:
    3,591
    Trophy Points:
    113
    Location (City and/or State):
    South of Southern California, but not Mexico
    I'll try and pull together other threads, by link, that have already beat this topic up.

    What I have found, most plants that tortoises like have oxalates in them. It's a 'secondary'compound with some direct uses by the plant, but for the most part seems to be a leaf eating insect deterrent.

    When looking at what it does in the tortoise gut we need to sort out a better C: P ration where the C is reduced by the amount of oxalates, so that a more true C: P can be determined. Not that oxalates are the only compound that precludes bio-availability of calcium, but it seems to be one of special concern as so many info sources so heavily indicate how horrible oxalates can be. My growing contention is that oxalates don't really matter in tortoises.

    This post https://www.tortoiseforum.org/threa...of-opuntia-with-citation.129949/#post-1217586 put me on this path of inquiry. Though opuntia is high in oxalates, it is a favored food as both a native diet item for some species, and an introduced diet item for many many more. It turns out even with oxalate burden in opunti, the C: P ration is still positive.

    a few more
    https://www.tortoiseforum.org/threads/oxalic-acid-not-as-bad-as-we-think.62761/#post-594792
    https://www.tortoiseforum.org/threads/oxalates-what-are-they.37761/

    $1 for any links to or PDF loaded here that have oxalate content values for any plants that we feed, any quote from the tortoise table and you'll be fined $100.
  2. dmmj

    dmmj The member formerly known as captain awesome Moderator 10 Year Member!

    Joined:
    Aug 15, 2008
    Messages:
    19,752
    Likes Received:
    7,008
    Trophy Points:
    113
    Location (City and/or State):
    CA
    (These ads do not appear for registered members.)
    What I have tried to figure out is does it bind 1:1 or some different ratio. 1:1 it may not be the best food but can always supplement more calcium rich food. Interesting about it being an insect deterrent, plants do not want their foilage eaten.
    KhairulTort likes this.
  3. Kapidolo Farms

    Kapidolo Farms Well-Known Member 5 Year Member Platinum Tortoise Club Tortoise Club

    Joined:
    Nov 7, 2012
    Messages:
    4,621
    Likes Received:
    3,591
    Trophy Points:
    113
    Location (City and/or State):
    South of Southern California, but not Mexico
    upload_2019-6-14_14-25-55.png

    In table 1, they use molar ratio. That's simple put as counting the molecules, not weight but count.

    Attached Files:

    RosemaryDW likes this.
  4. Kapidolo Farms

    Kapidolo Farms Well-Known Member 5 Year Member Platinum Tortoise Club Tortoise Club

    Joined:
    Nov 7, 2012
    Messages:
    4,621
    Likes Received:
    3,591
    Trophy Points:
    113
    Location (City and/or State):
    South of Southern California, but not Mexico
    @Toddrickfl1 if you know of the others, doubters on FB, please @ them in.
    Toddrickfl1 likes this.
  5. Kapidolo Farms

    Kapidolo Farms Well-Known Member 5 Year Member Platinum Tortoise Club Tortoise Club

    Joined:
    Nov 7, 2012
    Messages:
    4,621
    Likes Received:
    3,591
    Trophy Points:
    113
    Location (City and/or State):
    South of Southern California, but not Mexico
    A easier to read paper on oxalates and their effect of people, not tortoises. But even the dreaded spinach comes out net positive for calcium.

    Attached Files:

    Pastel Tortie likes this.
  6. ZEROPILOT

    ZEROPILOT Well-Known Member 5 Year Member Platinum Tortoise Club Tortoise Club

    Joined:
    Jul 16, 2014
    Messages:
    19,513
    Likes Received:
    34,758
    Trophy Points:
    113
    Location (City and/or State):
    South Eastern Florida (U.S.A.)/Rock Hill S.C.
    I've read that too much oxalate intake into a human body can contribute to kidney stones.
    Is that not an issue for tortoises?
    (Oxalates in foods like Spinach and Purslane)
  7. Mizcreant

    Mizcreant Well-Known Member Tortoise Club

    Joined:
    Nov 13, 2017
    Messages:
    1,302
    Likes Received:
    1,541
    Trophy Points:
    113
    Location (City and/or State):
    Cincinnati, OH
    In addition to renal problems, excessive oxalates have been known to cause problems with bone structure as well.
    ZEROPILOT and drew54 like this.
  8. Kapidolo Farms

    Kapidolo Farms Well-Known Member 5 Year Member Platinum Tortoise Club Tortoise Club

    Joined:
    Nov 7, 2012
    Messages:
    4,621
    Likes Received:
    3,591
    Trophy Points:
    113
    Location (City and/or State):
    South of Southern California, but not Mexico
    Based on NO result ever being found by vets, it does not seem to be a problem for tortoises. The U of Minnesota has a funded urolith research center, it's free to submit samples, and over 30 years of receiving samples (n=66 for tortoises ) no tortoise is reported to have any oxalate based 'lith. Another independent report looked precisely at tortoise liths, non were formed based on oxalates. Both studies are talked about here https://kapidolofarms.com/wp-content/uploads/2018/11/KapidoloFarmsTTPG.pdf

    I have read popular articles in magazine like "Reptiles" and heard vets in lectures issue warning based on human results, but none of those vets, when asked, did an actual analysis of whatever stone they are talking about and seem to have assumed what it is. Of stones analyzed, the vast majority are protein waste product concretions, which indicates to me the tortoise was water stressed.

    I'm not advocating feeding a spinach only diet, that violates the number one rule of tortoise diet (Variety), but there is no value in picking the spinach out of spring mixes either.

    As discussed by others, who's posts I linked in the OP, oxalates in any form, are a secondary compound in many plants. Opuntia being a common food, I focused on that. Their role is to inhibit animals from eating the plant, mostly leaf eating insects.

    It would seem that most plants have more calcium than calcium used up (bound) by oxalates, after all the plant needs 'free' calcium as well. So the issue, the real issue is, of the free calcium, is it a positive ratio to phosphorus. At least in the case of opuntia, it still has a C: P ratio of not less than about 10:1. Other plants, the oxalate bound calcium may turn this ratio opposite to what we desire for tortoise food. When calcium is measured in foods, there is not often any distinction made between bio-available calcium, and total calcium. So we get a positive C: P ratio of total calcium, not the more appropriate for our purposes, a C: P ratio of bio-available calcium.

    I imagine some folks are rolling their eyes if they read this far. Up your game, or be chicken little. The sky is not falling.
  9. ZEROPILOT

    ZEROPILOT Well-Known Member 5 Year Member Platinum Tortoise Club Tortoise Club

    Joined:
    Jul 16, 2014
    Messages:
    19,513
    Likes Received:
    34,758
    Trophy Points:
    113
    Location (City and/or State):
    South Eastern Florida (U.S.A.)/Rock Hill S.C.
    I appreciate all of the information.
    I've worried about the amount of Purslane my Redfoot eat out in the yard.
    Sometimes it's a lot.
  10. Tom

    Tom The Dog Trainer 5 Year Member Platinum Tortoise Club

    Joined:
    Jan 9, 2010
    Messages:
    45,619
    Likes Received:
    25,562
    Trophy Points:
    113
    Location (City and/or State):
    Southern California
    How does this all translate Will? Do you think its okay to feed oxalis and other high oxalate foods to the tortoises? Who will be the guinea pig? I throw buckets of tender juicy oxalis in the garbage every year. I'd much rather feed it to the tortoises if its not going to do harm to them.
  11. Yvonne G

    Yvonne G Old Timer TFO Admin 10 Year Member! Platinum Tortoise Club

    Joined:
    Jan 23, 2008
    Messages:
    81,746
    Likes Received:
    54,423
    Trophy Points:
    113
    Location (City and/or State):
    Clovis, CA
    Personally, I would not give 'buckets' of purslane or oxalis to a tortoise, however, if it's growing in their yard and they have free choice to eat it or not, I wouldn't worry about them eating it. Dudley's pasture has quite a bit of oxalis in one section. I don't see him graze that section very often.
    Last edited: Jun 19, 2019
  12. ZEROPILOT

    ZEROPILOT Well-Known Member 5 Year Member Platinum Tortoise Club Tortoise Club

    Joined:
    Jul 16, 2014
    Messages:
    19,513
    Likes Received:
    34,758
    Trophy Points:
    113
    Location (City and/or State):
    South Eastern Florida (U.S.A.)/Rock Hill S.C.
    They eat it and little else when they are allowed to roam the yard.
    It would be nearly impossible to remove it all.
    But not letting them roam the yard is an option.

Share This Page