Duck vent--does this look normal?

I am hoping that someone can help me out. We have had some real issues with our ducks lately. I had one to prolapse and die in less than 24 hours. Not even a week later, we had one become egg bound with an extremely swollen vent. So I'm kind of paranoid right now. I picked another one of my ducks up today and looked at her vent and I'm a little worried. I've posted a pic below but it almost seems like there is something coming from inside that is coming out and closing her vent off. Is this normal? She has been overmated by a very active drake lately. Maybe that would explain what this is? I hate to say it but I'm really not sure what a normal vent should look like and Google didn't help much.