Injured axolotl leg

[DrJade]

Hello. My full grown female axolotl was injured by her tank mate, who accidentally snapped her front leg. The leg appears broken or dislocated at the knee and the skin is damaged, stripped from underlying fascia over half her lower leg, see pics. This happened 4 days ago. I added extra Johns solution to the tank. She is using the leg, but I am worried it may become infected. Considering antibiotic baths, fridging and/or keeping her in a small box and doing frequent daily water changes. I did not consider ampuation originally, but wondering if that would be better as the leg is no longer straight and I think if it heals it will be permanently bent in the wrong direction. Any advice on whether I should use antibiotics, amputate, fridge or some combination or none of these? I am a physician and have an undergrad degree in amphibian embryology, so have alot of experience with handling complicated medical issues and laboratory care of animals. I was able to source neomycin and kanamycin which is on the safe list for axolotls. The tank water is 60F and she is otherwise acting normal and eating. Thanks in advance

 

[wolfen]

there was a post recently were one axolotl was injured by another and it was decided that amputation was best for their axolotl, might be worth a read through Will this need to be amputated/is it broken? Larger tankmate chomped on Arthur's arm and it looks really bad, but not completely mangled.

 

[DrJade]

I did see the other thread after I posted. It appeared to be a similar injury, but mine possibly not as severe. After doing extensive research and consulting with my professor from my amphibian embryology days, I have decided to fridge her and do a 1hr per day soak in kanaplex(kanamycin) using the dilution on the package.

I based this plan on the information in the U of K article:

https://ambystoma.uky.edu/genetic-stock-center/newsletters/Older_archive/Issues-24-30/archive/issue28/17-21%20borland.pdf

and by advice from my old professor who said kanaplex is frequently used on amphibians in lab settings It is broad spectrum and very strong so I decided on a 1 hour soak(also mentioned I. U of K article) vs a continual dose in the water.
Her wound does not appear infected and there appears to be an active blood supply in the leg. There is a small amount of necrotic skin, but I am going to leave it for now so as not to stress her with surgery.

Interestingly I found this article on wound healing in Axolotls and how it is different than humans:

A novel role for SALL4 during scar-free wound healing in axolotl - npj Regenerative Medicine

A protein previously implicated in stem cell maintenance helps the Mexican axolotl salamander regenerate its skin after injury. Karen Echeverri and colleagues from the University of Minnesota, Minneapolis, USA, analyzed gene expression patterns at different time points during wound healing in...

www.nature.com

Compared to humans..."In contrast, the Mexican ‘Axolotl’ salamander is able to fully regenerate the skin after major wounding.7–10 Previous work shows that at the end of the wound healing process in axolotls collagen remodelling and wound bed closure is complete, and the skin is restored to normal functionality. Thus, a common hypothesis is that axolotl and human have differing molecular mechanisms of cutaneous wound healing that directs towards scar-free regeneration in axolotls versus reparative scar prone healing in humans.

Until now, some interesting differences in the wound healing processes between these two species have been established. For example, a major difference between axolotls and humans is the speed at which re-epithelialization of the wound occurs.7,9–11 In axolotls this process occurs directly after injury; whereby keratinocytes migrate over the fibrin clot to close the wound within 24 h. Once the wound is covered, the keratinocytes will start to proliferate to thicken the epidermis. In contrast, human keratinocytes at the leading edge of the wound will hyperproliferate and then migrate under the fibrin clot to close the wound ~ 1 week after wound formation."

 

[wolfen]

it's good that you can get confirmation of safety with medications and treatment from your professor as although I find the information from the axolotl colony archives to be quite reliable, on rare occasions though the information can be contradictory, I've attached an article which although useful mentions the use of malachite green.
as to the recovery abilities of the axolotl most research deals with the regrowth after amputation and it's very rare to find a paper that deals with the regrowth/healing process without amputation being involved, that being said I remember reading an article once that dealt with an injury where the limb was damaged including the bone and it was found that rather than repair the damaged bone/limb the flesh regressed until the limb fell off and a full regrowth was performed (I will see whether I can find the article although no promises as it was some years ago that I read it)