I minimize wasted rats by have 2 feeding days. One for half my collection, and another day for the other half. If one is refused, I attempt to feed one in the other group.
Although this year would be my first cold season(breeding season), what I have done since both of my males and one female have gone off food is that I offer them every 2 weeks with the same system with the 2 different feeding days, only for the ones I know are off food of course. For the regular eaters I thaw the normal amount of rats.
Also, depending on how long I've had the rat out of the freezer. I have refrozen some rats without a problem. As long as the rat isn't foul smelling I would feed it off no problem.
When all is said and done, I could also just feed my boa. She takes everything every time, even in shed.
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