American Fancy Rat & Mouse Association

This article is from the Summer II 1998 AFRMA Rat & Mouse Tales news-magazine.


Mites On Mice/Flea Powder On Nursing Moms and Babies; Problem With Mites
Mites On Mice/Flea Powder On Nursing Moms and Babies

From our files
QI recently purchased some Frizzie mice from a local pet store. When I got home and set them up, I realized that they had mites. I have them in a separate room from all my other animals. Unfortunately, I think that the problem has spread. I have used the Zodiac flea powder for cats and kittens in the past; however, a majority of my females are currently nursing litters. Is it possible to dust the nursing mothers and the babies?

From our files
QI have been using Seven Dust 5% insecticide on my animals and in the litter. This seems to be making a big difference. However, the bag says not to be used on animals (cats or dogs) with young under 2 weeks of age. I’ve held back on animals about to give birth, as well as those with nursing young. If using flea powder, do you also hold back on nursing mothers and babies?

Scratching rat

ASome fanciers have dusted moms with babies, but most prefer not to. It is never a good idea to treat pregnant or nursing mice for mites. A product that works much better than flea powder, is Ivomec solution (Ivomec in propylene glycol). Only use on adult animals, not on nursing moms or babies. Your veterinarian may be able to mix up some for your mice. It only takes one drop behind the ear of each adult mouse to clear up the problem (repeat in 2 weeks). The dose we use is 1 cc ivermectin (Ivomec brand for cattle 1% sterile solution or Eqvalan Brand for Horses) with 9 cc dilutent (propylene glycol for Ivomec and sterile water for Eqvalan). Both are available through Omaha Vaccine Company (800) 367-4444. Karen Robbins

AAs a veterinarian I do not recommend using flea products or ivermectin products on pregnant or nursing rats and mice. These products can cause the babies to die in utero or before they are weaned from the mother. The underlying problem is that the blood brain barrier closes later in mice and rats than in dogs and cats and the many products are directly toxic to the brain before the barrier is completely formed. Mite infections are not usually fatal and if you want to treat your animals, than consider taking a short break from breeding. Separate the males from the females and wait until the young are weaned and then treat everyone twice. If this isn’t an option, than treat all cages of animals that do not have any pregnant or nursing animals. I prefer the Eqvalan product, since propylene glycol is not as easy to find. Carmen Jane Booth, D.V.M.

Problem With Mites

From our files
QWe have, for the second time, a frustrating problem with mites. How do you people keep from being eaten up with mites? The last time this happened, my children and I took all our rodents, mice, hamsters and gerbils for a visit to a friends’ house while my husband fogged the house and emptied all the cages. (He isn’t a rodent lover. He was that desperate.)

AWhen you have a mite problem, you not only need to bomb the house and wash the cages/put in fresh shavings, you also need to powder or spray the mice for a couple of weeks (1 to 2 days per week). Also, some people have kept a Shell No-Pest Strip up in the area for about a week. Wood cages are not good to use, as the mites seem to breed in them. Plastic, glass, or metal is the best. Mites are really very rare to get. Usually they come in from infected animals. If you have ever had wild mice in your house, it is probable that they are the source of the mites. As long as wild mice can get in, you may always have mite problems. If this is the case, then you might want to sprinkle some flea powder in the shavings every time you clean cages—even sprinkle some on the adult mice (always use cat flea powder/sprays). This should help keep it under control. Karen Robbins *

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Updated February 12, 2015