Red Eared Slider - Problem, maybe..

Question
hi there, i have a RES, and he is about 2 years old now. I have noticed today that he has a black, discharge coming out of his back side. I don't think it is normal. It looks kind of shinny, however it has not fully come out. When i come close to the tank, it goes back in. Can you let me know what this is and how i should go about helping my turtle with this, if it is painful.

Thanks in advance.

Answer
This is a 'prolapse'- the appearance of an internal organ that should generally be kept internally.

A dark organ that goes back in is often the penis, and if it is going back voluntarily it is called 'fanning'.

You can learn more about this in the medical section of http://www.austinsturtlepage.com