Can anybody help my bitch gave birth to 6 puppys this afternoon but a couple hours later gave birth to another i saw it take a breath but it was little so didnt look too good

So i have a dead puppy and she has bitten its leg off and its tail now 
Should i try to remove it or should i leave it there for her to deal with it?????

Please help

Take it away!

Thanks have taken it away

She wouldnt let me first of all but we distracted her

So thanks for the advice