We are not bringing in any new rats until this is figured out. I just picked up Monk and he has another symptom that I just noticed. He has hair loss on one of his testicles. I was just reading an article about myco when I clicked on this thread to check the response.

It definitely sounds like myco. According to the article, it also causes low litter sizes when they breed. His last fathered litter was only 6 and they all died at 2 weeks.

Is there anything I can do for him? And does the other male have it? What should I do for the colony? The other rats seem fine. I have All the females in other cages but their cages are in close proximity to Monk's cage. It says myco is highly contagious. Will all the rats have it?