A trick i learned with frozen prey is to poke a hole in the skull of the mouse or rat.I know this sounds barbaric,but it has worked for me.my female seems to strike fast and is less fussy.I have tried this with the same mouse before hole..picky and fussy ,after hole BAMM...almost instantly she strikes,weird but true..Read this in a book.something about the scent of brainmatter that acts as a hyper stimulant