Degus are delightful little creatures! They are becoming more and more popular, and I can understand why!
Not much research has been done on degu diseases. In fact, my textook I use for pocket pet diseases has less than a page of info on degus.
This new study published in the Journal of Small Animal Practice looked at the medical records for 300 degus.
The most common condition a degu would be seen for is dental disease followed by alopecia (hair loss) caused by self barbering. The next most common condition was cataracts of the lens of the eye, bite wounds and diarrhea (usually due to not being fed correctly.)
Only 38 out of 300 degus in this study were healthy! However, this number may be biased as healthy degus are not as likely to be taken to the vet as often as healthy dogs or cats.