If my XL rat you mean those that are over 400g; I would feed my ball pythons a 400g rat if they are over 7000g themselves.
All of my adults (2000-4500g) get 175-200g rats.
I have but don't make a habit of feeding larger retired breeder rats off to some of the bigger females and by bigger I mean 2500-3500 grams..I have one girl that will eat a full sized male rat and not even have a lump in her of course she 3600 grams so she's the exception and not the rule..but yea I'll feed off some bigger rats especially when the female is fixing to start breeding I'll get a couple of bigger meals in them and then step back to the smaller one's ..
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