When feeding gerbils, you should try to stun them first. They fight back a lot better than rats/mice & can inflict more damage. I don't normally feed gerbils but my neighbor had like 30 to get rid of so I used em up.

I stuned em by putting them in a towel & smacking against a hard floor. Not hard enough to kill, but hard enough that the gerbil didn't know which way was up until it was too late.