Pyoderma Figure 4

Figure 4: Stress related pyoderma in 15-month-old rat (Selene).
Case history and photos


The following is of 15-month-old female rat, Selene, a few days after surgery for removal of an inguinal tumor.

Clinical Signs

This rat initially presented with a dark scab (eschar) on left flank, along with darkening red or bluish/grey patches of skin on the same side.

Initial Treatment

Vet prescribed 0.15 cc (based on mg/kg) of Baytril and 0.1 cc of doxycycline twice a day, and the owner to return for a checkup in 3 days.


Pyoderma due to stress related to surgery.

Follow-up Treatment

On the return visit the pyoderma had spread. The rat was shaved and a culture was taken from 2 spots on the rat’s side. The doxycycline was changed to Clavamox at 0.1 cc (based on mg/kg) twice a day. Metacam was added for pain relief at this point at .05 cc per day. The culture came back negative but this was expected.

After being placed on Clavamox, the rat showed severe abdominal discomfort and experienced the side effect of diarrhea. Probiotics were then introduced along with placing the rat on a BRAT diet (banana, rice, applesauce, toast). In addition to the diet and probiotics live culture yogurt plus additional acidophilus was included, but this did nothing to stop the discomfort and diarrhea. The vet explained that some rats can be very sensitive to the drug, and for this reason the Clavamox was removed from the regime.

Because the rat was experiencing increased discomfort related to the pyoderma, the owner upped the original Metacam dosage to 0.1 – 0.2 cc for a brief time and applied a human anesthetic ointment, Polysporin for Kids, for topical pain relief . Once the pain was relieved the skin started scabbing and healing and the prognosis looked good. It was thought that the black scabs (necrotized skin) would probably be too deep to heal properly and that a debridement and suturing of approximated healthy skin might have to be done.

As it turned out the tissue ended up being healthy underneath, so happily no surgery was required, and no further extra treatment was needed. The Baytril was continued until the skin wasn’t open any longer.


Selene’s skin took over 4 months to heal, and was hairless, lumpy and scarred. It took an additional 4 months before hair started to grow back on the scarred skin.


Photo 1. Day 5: Following surgery, started baytril.   Photo 2. Day 8: Shaved, cultures taken, and put on Clavamox and metacam.   Photo 3. Day 11: Check up, Metacam decreased, probiotic added.

Photo 4. Day 13: Increased Metacam due to pain, added Polysporin for Kids, stopped clavamox.   Photo 5. Day 15: Decreased Metacam, healing started.   Photo 6. Day 20: Remained on Metacam, healing continues.

Photo 7. Day 26: Scabbing, itching, healing in progress.   Photo 8. Day 30: Remains on Baytril and Metacam.   Photo 9. Day 35: Healing continues.

Photo 10. Day 48: Healing continues, and remains on baytril and metacam.   Photo 11. Day 55: Significant improvement.   Photo 12. Nearly healed. Remained on Baytril and Metacam until new tissue growth closed area. Complete healing required a period of 4 months.

Case history and photos courtesy of Shelagh Hall and “Selene.”


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