Hello

I have noticed that my ball only wants to eat female rats.
I have had him for 2 month.
He is a very shy eater. He won't strike. He only eats if the rat is placed in he's enclosure. I called the previous owner and she said that he also only will eat if the rat was placed in the tank.
First when I got him he refused to eat(male rat)
Second time he refused also male rat. I then ordered 5 new rats online. They were all female, and he eat them all. Now I needed some new rats so I went to a local pet store, I buy him 2 new rats. They were male. He refused to eat them.
I will now order new rats for him online again.

My questions are:

Does your Ball python preference male or female, or doesn't it matter?

The last two rats from the local pet store, when they were defrosted, they seem skinny. And in a not so good condition.
Does your Ball python refuse a meal if the rat is to skinny?

Thank you for your time. Hope you can understand my English.