My Rat “Casper” was born on the 28th October 1998. When she was about 3 or 4 weeks old she and two of her brothers (from a litter of ten) were noticably smaller than their siblings.
Sadly the two little males died at 3 and 3 1/2 weeks old, respectively. By the time the rest of the babies were 5 weeks old, it was clear that Casper was always going to be quite tiny. The remaining 7 babies went to new homes, but I decided to keep Casperwith her mother a bit longer.
One night in December I noticed that Casper was running around the bottom of the cage much more actively than usual (she is normally a quiet individual). I thought she was playing, then I noticed her little body was completely rigid. Her right paw was clenched and the right side of her upper lip was curled up in an uncharacteristic snarl. She went completely limp, then slept for about an hour. When she woke up, she ate an enormous supper and seemed perfectly normal again. This happened regularly over the next few months. Sometimes she had very violent fits that sounded like loud banging from the cage, and at other times she just sat in the cage and didn’t move for several minutes. These episodes seemed to me to be very similar to the “grand mal” and “petit mal” seizures that humans have. Casper sometimes had nosebleeds too, and her back legs are quite “bandy”. However, she seems cheerful and bright -eyed most of the time, although she is still quite small for her age. I have not been able to see any clear pattern of when these seizures occur, although they do tend to happen when she has been out running around and getting excited. The first time it happened it was quite distressing; however, in my experience, I don’t believe Casper to be dangerously ill, or in any pain.