Feeders should not have a"bad" smell to them no matter the gender. A little ratty, maybe, and that's it. My guess would be that gender has nothing to do with it and quality of the feeders is what tipped him off. The female rats came from a reliable online source and were frozen and packaged properly so he ate them. The locally purchased ones were bad or off, so he refused them. Gender is purely coincidence in this case.Actually some of the male rats smelled pretty bad. The females didn't smell at all.