I realised earlier today that I had only weighed one of the larger rats I have so I tried weighing them all and the weight variation was 26 - 50 grams. I offered her the 26 gram one as that's within the 10 -15 % bodyweight range (226grams a few days ago). she has struck and strangled - I left her alone to eat and it appears that she ate it, I obviously haven't searched the tank but going by the behaviour and location of where the rat was its most likely consumed.