I live in Ohio, my daughter is 2 1/2 her biological father has never had anything to do with her. Then all of a sudden he wants a DNA test done. My current husband signed a affidavit to accept paternity of my daughter. Does her biological father still have rights to her?

Yes, I believe OH allows a challenge to paternity until the child reaches majority.

Were you married to your husband when the child was born ?

If no, he could not legally sign to confirm he is the father, since that would be illegal and fraud.

If you were married when the child was born, he can be assumed to be the father, and could have been added to the birth certificate at birth, but not signing affirming latter.

But yes, the bio father has the right to sue for his rights, for visits and to over turn any fruad done by your husband

If you were married at the time then your husband would be the presumed father. If you married afterward it would depend on how long afterward. But if he acknowledged paternity knowing he was NOT the father then that is fraud.