Illness/Sickness: Missing Foot.

Hi all. About a year ago Missy lost her foot. I've read that it can take upto six months, so now i am rather worried. I have read on many posts, the different reasons why the re growth could take some time, but i don't understand this one. She has a very good diet: earthworms, live & frozen bloodworms, wax worms, daphia, brineshrimp, etc. I always try her with new things, so her diet is very good. The temperature is always between 18 - 20 degrees, even now although it's summer , i use frozen bottles with salt in them, and also a damp towel covering the tank. All water parameters are perfect. She seems in great health, eats fine, enjoys playing in the bubbles from the aerator. She is about 10 inches in length, but maybe slighty overweight, her tummy is a little bit wider than her head. Does anyone have any ideas as to why it hasnt grew back yet? I thought maybe she had something wrong with her, that never had any symptoms but i'm not sure this would happen.
Thanks so much in advance!

I think sometimes 'lost bits' don't grow back. there is a thread somewhere about with someones axies that arrived with no feet and the most updated photos show a little growth on some limbs and none on others (from what I remember).
My male adult axie has a shortened gill on one side that has never grown back to its full length, I think sometimes these things happen, just like some axes regenerate with two feet, or extra toes. It's nothing we have done wrong as axolotl owners, I think it is just another thing that makes our axies quirky and individual.

How old is your axie? I read in the THF book by Scott on Axolotls that older lotls regeneration diminishes with age and sometimes limbs may not grow back at all

Hi Lacey,

Adult axies, particularly the older ones, take a longer time to regenerate compared to juveniles.

The rate of growth also depends on how severe the injury/amputation was. If a limb was amputated close to the body, the regeneration would take months or even years, compared to an amputation at the point of the foot itself.

Any concurrent infection on that limb will retard its renegeration.

Keeping the tank conditions and nutrition at an optimum level will definitely accelerate the healing process.

Also it may not seem outwardly visible to you, there might be some regeneration happening very slowly at a microscopic level. For example, the bony cartilage may be remodelling, the skin and connective tissue or vascularisation of blood capillaries may be slowly reestablishing itself.

The best way to determine if there is any regeneration is to actually take serial photographs, for eg. one each month, you might even want to try measure the limb, although there really is no absolute necessity.

Regeneration may not be perfect. The regrown region may be deformed or even aplastic/hypoplastic, meaning it terminated its growth and regeneration earlier than norm. There is a genetic component to this.

At the end of the day, your axie will still remain as the same pet that stole your heart the first day you got it sans one less limb. The appeal will still be retained though.

Cheers.

Hi Rayson,

Is that true that Axolotls gills atrophy with age and they become more dependent on breathing cutaneously and through there lungs? Ive noticed on the young ones under 10cm they always have quite big gills. I read that Axolotls actually undergo cryptic metamorphosis developing lungs like adults and I guess this applies to the fact that they are neotenous and they develop adult reproductive organ as well.

Hi Zolotl,

Axies do rely on three main forms of respiration - via the gills, via buccal pumping (gulping air at surface for rudimentary lung function) and transdermally through the skin, notably the mucocutaneous junctions such as the lining of the inner mouth.

Being neotenic, they do sexually mature while retaining larval features. Their reproductive organs mature while in a larval state, like you correctly stated.

There are more contributing factors to gill filament atrophy than just age. Assuming the axies are free from pathology/illness, gill shrinkage can occur when they are kept in oxygen rich water. Longer gill filaments have a greater surface area to faciliate gaseous exchange. When the water is oxygen rich, there is less need for this big surface area and some axies will get shorter gill filaments. There is a genetic component to this. Note that these filaments will be shorter but not deformed or twisted. Gill filaments that appear misshapen can indicate pathology.

Age does play a part. Juveniles appear to have longer gills/filaments partly due to the proportion to body size. When fully grown, the gills appear smaller due to the larger body size. i would also think full grown adults have fully developed their 'alternative' breathing mechanisms, such as a wider skin surface area, established vascularisation network of capillaries and venules and complete development of their rudimentary lungs. These will supplement gaseous exchange. As such, much like oxygen rich water, there is less need for a large surface area for gill filaments. Again, the extent gill filaments become shorter has a large genetic component and different axies will display varying degrees of gill shrinkage.

Cheers.

Thanks very much for the replies. I really appreciate it! She is 2 years and roughly about 3 months. I will definetaly take pictures and see if i can see a difference, also i will try to measure it not sure i'll have much luck there though! When she lost it, the leg/arm part did grow back, but the actual foot itself did not, so right now it's still a stump. I've always had doubts in my head that i was doing something wrong or there was more i could be doing, but i'm glad that's not the case! If you's are interested there is pictures of her on my page, not very good ones, as you will see some were when i just got her, and had small gravel in the tank (i found out a week after she was home this was bad) Also algae blooms,when her feathery bits were hardy existant (but they are all back now) and some that don't show her real beauty, but you can see the missing parts. Sorry there isnt any updated ones, my camera dosent charge anymore, and my pc connecter seems to have grew legs and ran away! I will keep you's updated in the future if i can see anything new.
Thanks again!

Lacey.

Hi Rayson,

If your saying there is genetic component to gill size then is there possible natural selection for gill size in certain populations? not that there is much of a natural population, and if its genetic then how can the gills change size in more oxygen rich water? this sort of doesn't make sense.

cheers, Zolotl

one of my axies had his leg bitten on 2 times and both times it has grown back fully, he has now grown back 3 legs but he is still quite young. They seem to be stumpy for quite a while then in the space of a day a leg will appear!

My other juvie axies leg has just grown back, in the space of an evening after being a stump for about a month.

Hi pinkangel,

Whilst that is amazing tribute to the regenerative abilities of axolotls by my count thats four regrown limbs, so I was wondering if you have seperated your axolotls or are they all housed together?

Hi Zolotl,

Every animal has a genetic potential. However the phenotypic expression (the outward visible characteristics) are influenced by other external triggers and factors. Let me give an example.

In the case of the axolot A, genetically it has the potential to grow really long gills of lets 5cm, and Axolotl B has the potential to grow gills of maximum 3 cm under ideal conditions. In very poor water parameters and temperature, both axies will have shrivelled gills nontheless. Similarly, in very oxygen rich water, Axolotl A may only have a slight reduction in gill size whereas Axolotl B have more significant notable difference. It is their predetermined 'limits' to their growth.

In humans its the same thing. One very popular example is obesity. There is an 'obesity' genetic predisposition. Meaning some people put on weight very easily (combination of resting metabolism/ hormonal balance etc) while others can feast all they want and still remain rather lean. However, exernal triggers play a part. A person genetically predisposed to be fat can still minimise that 'potential' by regular exercise, a good diet, having enough sleep etc. Hence the genetic 'limit' is partly influenced by what happens externally as well.

Cheers.

Hi Rayson,

I see what you mean, is there then some truth in that wild type and melanoid axies are more aggressive to other axolotls and coloured morphs? Is this a genetic trait linked to pigment migration to the brain, somewhat affecting brain development or possibel hormonal changes (I was reading an interesting earlier discussion you had with someone on colour genetics and pigment cells). I guess theres hasnt been enough studies on this subject so it'd hard be to know for sure
As you mentioned in your studies of cats I think I recall the melanocytes influence different organs in the body as they migrate form the neural crest interact with different organs sometime causing diseases, if this applies to the brain im not sure, anyway its a really interesting topic.

Sorry to go off the main topic, but I guess it has to do somewhat with physiology and regeneration:happy:

Hi,

Yes wildtypes are noted to be more aggressive and strangely particularly aggressive to non wildtype conspecifics. There are no studies done that really explain this phenomenon. I am sure there is a genetic component involved as well.

In australian budgerigars, the green/yellow wildtype is also more aggressive to non wildtype budgies like lutino (yellow), albino and other colour variants. Studies has suggested there may be an innate 'discrimination' to protect the main flock. Other colour variants 'stand' out from the flock and draw attention to predators etc. For example, a flock of green budgies with a sudden white budgie in the midst. Its been a very long time since i researched on those areas so i am not up to date with the latest findings. However you can look through MedLine/Pubmed type search engines and look up for scientific articles to read about.

Cheers.

bam bam was already missing a leg when i got him, and then his older sister decided to get a bit nippy one day and bit his legs off, i removed him and my other juvie swiftly!

Wilma lost her leg as she managed to wiggle her way under the divide and into pebbles side of the tank.