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Mice/Mouse with raw tail


Alfalfa 2
Alfalfa 2  
QUESTION: I have a 1 year old field mouse that has raw spots on his tail. The appeared 3 weeks ago and I took him to a vet but he could not get a scraping from it because he could not find a way to catch him. He ended up getting free in the examination room and finding a hiding spot behind a cabinet. The next morning he was in his cage and they tried again but to no avail.

We decided to treat him for a staph infection (oral antibiotics for 10 days) .01 cc twice a day. I put it on his oats for him to eat. We also started treatment for mites with Revolution .05cc once every 2 weeks for 4 weeks. I spray it on him with a syringe behind the ears and rub it in.

He looked pretty good after the antibiotics but the last week his tail has been progressively worse. I have changed his diet. Before it was 100% oats until the vet said I was raising him on junk food. I have been giving him the sunflower and small seeds out of a hamster mix. At first he wouldn't eat it but he has developed a taste for the smaller seeds and a I still give him about 20 oats each day.

I have been changing the cage every two days and washing everything, including his wooden house in a bleach solution. I let it sit in it for 4-5 minuted. I use alfalfa that has been sterilized by heating in the oven @ 140F for 45 minutes for bedding.

Up until this problem he seams to have been happy and healthy and I had not sterilized the bedding but had been using alfalfa for the last year. (He was raised from a pup from a litter that was found in a alfalfa bale. That's why I have been using alfalfa as bedding)

I called the vet last week and we talked it over and agreed to go two more weeks and see what happens. He would prefer to use Ivermectic to treat the mites but it is impossible to trap him and hold on to him. We have discussed sedating him to get a better diagnosis but there are risks associated with that also.

I would appreciate you opinion on the treatment. How I am cleaning the cage. I'm wondering if he many be having a reaction to the bleached items. I didn't want to disrupt his environment while he is sick (uncomfortable) by changing out his living hutches but maybe I will have to.

Thanks for any input. I have attached two photos showing his tail.

ANSWER: Dear Brian,

Unfortunately I am not a vet-- this is not a common problem, so I am not familiar with it-- but I have sent it to a few people who know more about medicine than I do. You will receive an email saying I have amended the answer, when I add to this with more information.

In the mean time, please answer a few questions that I have.

Is it an exotics/pocket pets/rodent vet? If not, you should definitely go to one. A cat and dog vet really has no real knowledge about rodents, whether they think they do or not. The idea of mites causing such a problem is a strange one; as is the idea that ivermectin is better than Revolution; and as is the application of Revolution as a spray- and more than once a month. In other words, I am unsure about your vet. It is very important to have an experienced rodent vet. Find one asap if yours is not one.

So you say the antibiotics did help while he was on them, but you stopped and it came back? Or it only helped a little? What antibiotic? That is important to know.

Also: you say you changed his diet *after* the tail brought you to the vet? Because if it was before, then allergy is very likely. Even so, whether yes or no, I suggest you now put him in an almost completely hypoallergenic environment. Wash the cage with plain water; use only paper towels for bedding; and feed him only cooked brown rice. Usually I say oats, but he may have developed an oat allergy- which would explain the improvement after the vet visit. If allergies were the problem he would start to show signs of healing within 3-4 days. You might as well do this before returning to the vet.

Last, you can stop bleaching. Bleach is very noxious and can irritate nasal passages, inducing respiratory problems. Just use a little non detergent dish soap; water with white vinegar; Dr Bronner's (not peppermint) soap; or just plain water.

Also he should be eating a store bought mouse and rat seed mix. That is the only way-- besides blocks or pellets-- to get the right nutrition in him.

It will help to have these answers; in the mean time I will see what some more medical-minded mouse people have to offer.

I wish him the best of luck and health-- that tail looks dreadfully painful!



---------- FOLLOW-UP ----------

QUESTION: The vet is a pocket pet specialist. He was willing to look at my wild mouse after everybody else turned me away.

The antibiotic is TMC. The pink stuff.

He was saying that it is an unusual condition since mites generally show up as spots on the back behind the the neck. He consulted with other vets that have been using feline Revolution as an alternate to Ivermectin and stated he was not that familiar with it. I had a little difficulty understanding the dose for the Revolution being .05 cc which is 5 times the .01 cc for the antibiotic prescribed. If I compare the volumes using the syringes. the revolution is much less. They marked the dose as I gradation on a 1/2 cc syringe. It is an incredibly small amount. I was supposed to administer it to the skin but he does not have and exposed skin other than on his tail (which he does not permit me to touch - Alfalfa). The place with the least amount of fur is behind his ears. We discussed the fact that I do not know how much is actually being administered to the skin. That led to the let's wait and see but if it gets worse call. The condition of the tail seemed to vary from worse to better for the week after our discussion (1.5 weeks ago. The last few days it looks to have gotten progressively worse (the worst it has been). I was planning on scheduling another visit but wanted to see if I could collect more information from people knowledgeable on mice. Thus this thread.

We kept him on an all oat diet during the 10 days of his antibiotic treatment. I only forced a change in diet after. I will go to the cooked brown rice this evening. And change the bleaching to just cleaning with warm dish detergent water. Is that adequate to kill/remove mites and eggs if that is the problem? I give him new cardboard tubes each cleaning and also change out some cotton rags I give him to make bedding. He seems to like them.

Thanks Natasha

ANSWER: Dear Brian,

Ironically, it may be because your vet doesn't know cats and dogs that he doesn't know much about Revolution! : )). It is prescribed for cats and dogs but those of us in the rat and mouse world use it on rodents and it works well. Revolution is applied as a tiny amount on the skin on the back of the neck. It should go on the skin and not the fur, so if you can't get him calm enough to do that, behind the ears is great *as long as he doesn't wash for 10 minutes while it dries.*  It is more effective than ivermectin, and it works by killing anything that sucks the mouse's blood for a month.  I am actually writing this more for your vet's and your edification; because I really do NOT think this is mites. I do not think you should treat again with Revolution or ivermectin in any form.

The amounts of the medications are not comparable. The Revolution is a very, very strong drug. Even a dog gets only a few drops.


The rest of this is a work in progress. I have been consulting various people and don't have every response yet.

The other possibilities I have been discussing with people are allergies, bacteria, ringtail, or fungus. I haven't gotten any comments on fungus yet, which is an idea of my own, so it may well be a dead end.

My opinion is we do everything possible that makes sense (mites don't make sense).

Allergies would be a Godsend right now because that is easily controlled. You are putting him in a (near) hypoallergenic situation as starters. He may still need an antihistamine. We do give rats liquid Benadryl, so I am sure it is fine for mice. I have yet to figure out the dosage.

A bacterial infection, which your vet suggested, is still a possibility. One person said it would be hot and maybe smell bad if it were infected. I do not know yet what antibiotic to suggest-- I have put that question out. I do not think there is an antibiotic called TMC-- could it be TMS? If not, there is something called TMC but it is a viral culture, which makes no sense to me. I am thinking maybe we should try amoxicillin, but am waiting for help on that one too. I'm no antibiotic expert.

Ringtail is a condition in which the tail develops a ring kind of like a hose clamp squeezing in on a hose. The portion after the ring in a simple case usually eventually drops off. Several people have offered this possibility, including a vet. I do not think this is it, but I don't know if there is much you can do for ringtail anyway besides preventative-- raising the humidity to at least 50%. I may learn more that can be done.

So as to what you can be doing right now:

1. Hypoallergenic situation

2. Make sure the humidity is high enough (maybe he needs a humidifier).

3. Get some liquid Benadryl.

4. Get and apply some Neosporin Plus to the tail, which has direct antibiotic but also pain relieving properties. I know it will be hard to rub it in, and it shouldn't be very much-- you don't want him ingesting a lot of it, though some won't hurt. So you will have to figure that out.

I am going to keep working on this with you until I have done the best I can. That tail just looks terrible. Put off going to the vet till I write back, so that if and when you do go, you will have a complete list of ideas that other knowledgeable rodent people have to offer.

Send a followup tomorrow afternoon to give me a chance to get some information.

Keep me informed on your side if anything happens.



---------- FOLLOW-UP ----------

QUESTION: Hi Natasha,

The antibiotic used was trimethoprim sulfate.

I talked with somebody familiar with the animal rescue organization connected to the SF Zoo and they say many rodents develop psychological disorders from captivity. The assumption is there is not enough stress in there daily life. There recommendation was to contact a local animal rescue organization. I have not done so. I contacted them a year ago when I first got him and they were mostly concerned with possible diseases associated with keeping a wild animal. I had his fecal matter tested for HV as well as 7-8 other standard disease for lab animal;s by a zoological firm and everything came back negative and we decided to keep him. It would be a cruel irony if caring for him has caused his current state and we are prepared to do what is best for him if need be.

I contacted the vet to also and he independently offered the diagnosis of a possible compulsive disorder. There is no literature on rodents but dog and cats develop a compulsive chewing disorder that often can be corrected by amputation of the tail or administration of an anti anxiety medication. Amputation of the tail is a last resort. We discussed the possibility of an allergic reaction and that we would investigate a hypoallergenic situation and see what happens. He stated (based on dogs and cats) that it can take up to 90 days to see improvement. He gave me a solution of Chlorhexidine to spray on his tail to help prevent bacterial infection and recommended possibly replacing his daily water source with a Prednisone solution(.01mg/ml)to help mitigate the desire to chew during the evaluation time. I have not used it yet and am waiting for more input.

It worries me that he has an unusual condition. He appears to not be in significant pain (unbelievable to me) but the vet thinks it may be his instinct to act normal to prevent appearing weak. He seems to enjoy interaction and being rubbed which he gets quite a bit of lately. Thanks to you and your sources for helping.


Hi Brian,

He can't live on just rice for that long, though.  It doesn't take a person very long to show a positive reaction to removal of an allergen. Luckily, mice are more like humans than they are like dogs.  Benadryl would help too. I didn't get an exact dose on the Benadryl but I myself would use 0.03-5 ml of the liquid, twice a day, for a couple of days. Of course the tail won't heal, but it should look a little less raw within 5 days.

The comments I got were that it does look chewed; and that the antibiotic was used for too short a time. They recommend Baytril. I find your vet and his methods a little strange, and I have never heard of the antibiotic he was using, though maybe it is specifically for staph. Anyway 3 weeks is recommended for an infection such as that may be.

If you do think he is chewing, what he needs are more distractions. A big cage if possible; lots of things to climb on and through; maybe some treat boxes where he has to chew through the box for the treat; a walnut just partially cracked so he knows something is inside, etc.

Also that the dose of Revolution was far too high. My little dwarf rats, double the size of mice, get about 0.02 ml.

The other comment I got was that I had better talk to you about husbandry, which I had planned to anyway... Alfalfa needs some kind of substrate on the floor of his cage because otherwise he is sitting in his own urine, which can even burn- especially his tail. People most often use either a paper based litter such as Carefresh, or an *aspen* wood litter, though there are other products which work great too. Be sure not to use pine or cedar, because the oils are very harmful to their respiratory systems. I mentioned that he needs a balanced mouse mix, once his allergies are under control. Take out the sunflower seeds and corn at first, because those are very common allergens.  Always take out any raw peanuts, because the molds they carry are toxic. I haven't seen the rest of the cage but I am sure he has a wheel, the next most important thing after water and food and a nest (in my opinion, what comes after the wheel are the toilet paper rolls!).

I hope that between us all we have figured out a solution. That little tail looks awful.

Keep me posted :)




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I can answer questions about raising mice and caring for them as pets, with knowledge from my 38 years of having fancy mice as pets. I have NO MEDICAL TRAINING and you should take a sick mouse to the vet; but if you simply can't, I will try to help you. I LOVE PHOTOS!!! I ALSO LOVE UPDATES! Let me know how the little tyke is doing later on, for better or worse, especially orphans. It also helps me to help the next person. Please first search first: use 'Natasha Mice Mouse' with whatever else your question includes. Or check out these links: **** YOUR FIRST MOUSE (my video; rough draft): **** TEN VIDEOS ON RAISING ORPHANS: **** SEXING MICE: **** And some GREAT MOUSE INFO SITES:


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