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Testing mouse for allergies

21 15:14:23

Question
Mouse scratching
Mouse scratching  
QUESTION: Lately I've noticed that my fancy mouse has been scratching a lot. I've done research and I know it be mites, allergies, or chronic scratching. For the mites, I've bought the 8-in-one mite spray at the advice of another allexpert-- no change. For the bedding, even when I put her simple box with shredded paper she would still scratch.
One thing I've noticed is that she scratches less when she is somewhere unfamiliar ie, a chair in the kitchen or a small table in my room.
She seems to be in so much stress and I just can't stand watching her scratch so much. She has been losing fur around her eyes most prominently, but also behind her ears and neck. Her eyes are puffy and watery as well. However she is still eating drinking, and quite active, though maybe a bit weaker.
What do you think is causing her constant scratching and what can I do to relieve it? It is killing me watching her like this and being unable to do anything. None of the vets in my area will even see mice, so I'm limited to scouring the internet for help.

Thank you so much,
Amy

ANSWER: Dear Amy,

The poor thing sounds absolutely miserable.

If the 8 in 1 didn't work, first question: Did you shake it well? It has basically no effect if you didn't; second, will one of these vets at least give you some Revolution? it takes just a drop-- like on the flat end of a toothpick-- rubbed carefully into the skin and not fur of the back of the neck, to kill any parasite that bites the mouse.

On the other hand, at this point allergies sound pretty likely, especially with the reduced scratching out of the cage (which could also be due to distraction). I gave another questioner the following advice about itching:

"If treating for mites does not help *at all* after three days, the problem is something else.  Besides mites, fur loss and itching can mean ringworm, some form of mange, or allergy. I'm not a vet, and don't have the mouse in front of me, so I can't be sure these are the only possibilities, nor can I diagnose it.    Ringworm can be diagnosed by the vet with a black light.

"Let's examine the allergy component, which is something you can deal with at home.  An allergy could be to a new substance or the sudden development of a reaction to a familiar one.  Has anything changed in or near the cage recently? New food, new bedding, hair spray, air freshener, furniture polish, anything?

"Second, you might think the mouse wouldn't suddenly develop allergies at this late age. In people, however, this can happen. The following is from my knowledge of people allergies-- since mice are used to study people health, they are likely very similar.  First, allergies can be developed by overexposure to a substance. This is why so many cat lovers are allergic to cats. Growing up with cats exposes them to cats enough that they develop the allergy. Thus I am now allergic to mice and cats (a couple of 24-hour Loratadine a day make it possible for me to continue to enjoy my pets). This goes for foods too. I developed allergies to both garlic and rosemary from overexposure, one over a period of time and one from overexposure within one rosemary-packed week(!)  The second way an allergy can be developed is simply due to age.  There are ages at which allergies are likely to appear and disappear. With people it is about around ages 5-7, 10-12, 18-21, mid-thirties, and probably later too.  I developed very severe hay fever very suddenly at age 21. And my cat allergy suddenly became manageable in my late 30s. You can tell why I know about allergies!!  So mice may have cycles during their lives as well.

"So, what to do about allergies? You need to identify the substance that is causing the problem.  The most obvious is the bedding. Simply try another type of bedding.  More complicated would be a food allergy. The most common food allergies in mice are to corn and sunflower seeds.  Try removing these.  If after two days the problem doesn't improve at all, you can be more drastic and choose one food to give the mouse alone. If the allergy remains, try a different one. It's unlikely the mouse will happen to be allergic to both substances, so if that doesn't work, it's probably not an allergy.  If the allergy does disappear, however, then you can introduce each food separately one by one every two days, until you find the culprit. If the symptoms don't disappear, it's very likely not an allergy."


Another time I gave this advice, which is a little more detailed as to method (pardon me for being lazy today):


"Strip down her environment to as hypoallergenic a situation as possible and see what happens. This is going to be complicated, but you love her very much so I'm sure you won't  mind.

"Clean her cage and plastic/metal accessories just by washing thoroughly with with water. Then just give her paper towels as bedding. For food give her oats. Make sure you use no chemicals in the room at all-- no air freshener, furniture polish, cleaning agents, etc. Do this for 3 days and see if the symptoms recede.

"If the itching stops, start to add types of food. If she has a seed mix, you will want to separate out the seeds by hand! You can change something every day, but if she sneezes you will want to go back about three days worth of materials. At some point when she has a somewhat varied diet, the change you can make is to give her decent bedding again. If you use wood, the *only* safe kind is aspen. Do sunflower seeds, and then corn, last, because they are common allergens. Never give a mouse peanuts; and if they are in the mix, always take them out.

"As I said, go back three days' worth of changes if she begins sneezing or itching again, and try something else instead of what you tried. This way you will find out what she is allergic to."


Let me know if you have further questions. Good luck.

squeaks,

Natasha



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

QUESTION: Thank you so much for replying so quickly to my question.
I will try everything you suggested. For the oats, is it okay if it is Quakers old fashioned oats? I should just give her nothing but oats for 3 days? Another quick question: she loves pumpkin seeds, so I usually give her one. Do pumpkin seeds have any adverse effects on mice? ( besides their fatty content).
One reason I am wary of using the mite spray is because it seems to irritate her more. I put just a few drops on her and she would become obsessive with cleaning and even scratching herself more. Does this mean anything?

Thank you so much once again, I will try to give you an update as soon as possible.

Amy

ANSWER: Hi,

It is unclear to me whether you treated her completely or not. It is not nice stuff and hurts some mice's skin. For this reason I sometimes recommend the version meant for birds, which is half the concentration.

Yes Quaker oats are fine. It's not a great diet but for three days it should give her body a chance to get all the toxins/allergens out.

Pumpkin seeds are delicious, nutritious, and as likely to be allergens as anything. No treats while you are allergy testing of course, but in general it's fine unless she gets fat.

Best of luck!

Squeaks,

Natasha



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

QUESTION: Thank you so much!! Yesterday I washed out her entire cage and let it dry in the sun, and replaced all her bedding with shredded paper towels and toilet paper. She is still scratching a bit, but considerably less! She seems much happier now; I cannot thank you enough!!
I'm sorry for asking this if you've already mentioned it above, but after the three day diet of oats, what is safe to give her?
I've been using the Kaytee granule bedding. I suppose she's allergic to that now, so I will switch to Carefresh. This is a good brand, unlikely to cause allergies, correct?


Thank you, thank you, thank you so much! Myself, along with my little mouse is extremely grateful. Hopefully she will continue to improve over the next few days!

Amy

Answer
Hi Amy,

I'm thrilled that she looks happier. Common allergies are both to litter and foods, a well as pollutants in the air, so don't assume it was the litter.

For the allergy testing routine, what matters is that you know exactly what causes the problems. So, you can make a couple of changes at once, but only every three days, so if a problem develops you can go back and undo it and figure it out. For the foods you can choose anything (on a normal mouse diet of course) as long as you keep track. If you are going to feed her a mouse seed mix, you should actually sift through and keep complete track of which seeds you give her. If you want to try her on vegetables and fresher seeds and grains, that's fine too. Don't add more than three items, all at once, every three days. When she remains symptom free, try the next 1-3 changes.

My suggestion is to keep her in the sterile cage for a little while a you accustom her to some foods, rather than continuing with the oats and trying out the litters. And make no other change at the time of the litter change, because it is an extremely likely factor. The other things to definitely try only singly are corn and sunflower seeds, both common allergens. And don't assume you have found the problem when you find something that makes her sick; she may have multiple allergies, both to bedding and foods.

When you are trying beddings, try aspen bedding as well. Both Carefresh and aspen can cause allergies, but hopefully one won't!

There is a bedding, I don't remember the name, which is like little squiggly folded pieces of brown paper, and it seems to me to be a less likely allergen; it is awesome to tunnel in, too. And it is great because only the bottom layer gets gross so you use a lot less of it when you clean the cage. But I don't remember the brand.

Do let me know how it goes. Let me know what order you tried things in. Once you figure out what thing or things she is allergic to, she should be fine.

Best of luck!

squeaks n giggles,

Natasha

PS if she still seems itchy in the pristine environment after three days, we have to go back to thinking about mites.