Ectoparasites Figure 3

Fig. 3: Lice in 3 male rats (Charlemagne, Kylian & Stiles).
Case history and photos

History/Clinical Signs

Charlemagne, Kylian & Stiles are the first rats that I have kept as a group. All my prior rat experience has been with single rats. When Stiles started getting bite marks and scabs one of the first thing I did was have him checked by the vet (skin scraping) for mites. He tested negative, and in a while with weekly toenail trims the scabs cleared up. It seems that Stiles, at the bottom of the pecking order, had simply suffered a beating to keep him in his “place”, and has sharp toenails and sensitive skin.

A couple of months later it happened again, but didn’t start getting better like before. In fact he continued to collect a new bite wound every few days. Kylian, had a couple of wounds that weren’t healing, too. I was at my wits end, and beginning to wonder if the boys simply couldn’t get along. After Kylian had debrided the wound on his back for the third time (each time making it larger) I decided that I simply couldn’t deal with this without help, and it was off to the vet.


Lice! Lots and LOTS of lice!!! It seems that I must have brought home a box that had some nits on it, and gave my boys a toy which, in turn, gave them lice! I hope the pictures that follow will help someone else figure out what may be troubling their rat. If I hadn’t been thinking it was just pecking order squabbles I might have been on a lice/mite hunt sooner. It certainly didn’t help that Charlemagne, the alpha rat, showed no signs of any type of wounding. Obviously external parasites bother some rats far more than they do others.


Treatment begun with Ivermectin.


Resolving with ongoing treatment and prevention.

Preventative Measures

Freezing bedding & boxes (if you have a large enough freezer for the boxes) can kill any nits (eggs) that may be on them. If you don’t have a freezer, you can store them for about 4 weeks. Rat lice nits should hatch within 20 days, so I’m going to wait a little longer to make sure the hatchee’s have died!



Photo 1:  Stiles on September 23, 1999
2 days after the first Ivermectin treatment.


Photo 2: Stiles & Kylian:
The wound is actually smaller than it was when the lice were discovered.

Lice not obvious

Photo 3: Charlemagne, September 23, 1999:
Seen here on the same day as Stiles & Kylian, does not appear to show visible signs of lice, however, they were indeed present!

Case history and photos courtesy of Virginia Simpson


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