Shell Rot

is another ‘catch-all’ term for a variety of conditions that can
include bacterial, fungal, or environmental factors. In most forms of
shell rot, micro-organisms get under the protective layers of the
scutes and begin to ‘eat away’ at the tissues they find there. This
means that there needs to be a pathogen in the habitat, and usually
some form of damage to allow it to get under the top layer of scutes.
An example of a specific form of this type of shell rot is Septic
Cutaneous Ulcerative Disease (SCUD), which is caused by the bacteria
most often associated with shellfish. SCUD is most often associated with
aquatic chelonians.

shell rot (dark pockets or pits, bad smell, etc.) is most often bacterial, while ‘dry’ shell rot (‘cheesy’ growths) is rarer and
usually fungal, but any form of rot causes damage that invites
secondary infections and other complications. Shell rot can eat deeply
into the shell, causing more severe issues, and even death.


  • Minimize the growth of
    bacteria, viruses, molds and
    mildew in the habitat.
  • Arrange things to minimize scratches,
    abrasions, and
    chips to the shell.
  • Prevent overly-wet substrates. These conditions can lead to environmental ‘rots’ that behave like ‘immersion foot’ does for humans. In my opinion and experience, wet acidic
    materials such as sphagnum mosses seem to make things worse.
  • Bacterial and fungal forms of shell rot are infectious,
    new animals should be quarantined and if one animal shows it, all
    animals should be monitored.


  1. Isolate the affected
    tortoise(s) someplace with a dryer, cleaner substrate (see Nursing Care).
  2. Correct any
    issues in the habitat, environment, cares, and diet.
  3. Clean the
    affected area with gentle scrubbing or
    scraping to remove
    loosened materials. Try to remove all dead, dried-out, or damaged scute
    materials, but do not force anything.
  4. Swab
    the area completely
    with a multipurpose skin disinfectant such as Betadine Solution. Let
    dry completely. Betadine is effective against many micro-organisms, but
    also inhibits healthy growth so do not use it past the first 2-3 days. This may be all you need to do for a minor case.
  5. Treat the
    affected area twice a day with an antibiotic ointment,
    preferably something like silver

    sulfadiazine ointment or 2%

    mupirocin ointment. Keep the tortoise on newspaper or paper towel
    a couple hours or so to let the ointment work.

  6. Repeat ointment
    for about a week. Re-evaluate.
  7. If the antibacterial is not doing anything, switch to or add an anti-fungal ointment. Any over-the-counter antifungal used for humans will work, such as that for athlete’s foot or ‘jock itch’. Use for a week like steps #5 and 6 above.
  8. Contrinue treatment until the plastron is smooth, dry, odor-free, and shows no
    signs of discharge. 
  9. If

    it does not help, see a vet or other expert.


forms of shell rot, caught early and treated aggressively, should be OK
although it may take months or even years for some of the shell damage
to fully heal and there may always be scars.


Edited 2-25-2013 (C) Mark Adkins