Yep! It could also be those medium rats too. Try a small, just weaned rat and see what he says about that, or try 2 mice per feeding.

Darn teenagers! I have a 1300g(could be bigger now, she's hard to weigh unless she's in a pillowcase) 05 female though that hasn't once missed a meal. She's a bit bigger than her britches though and thinks she can fling herself OUT of the tub at feeding time. She's a turd bird, hehe.