<<John Holmes says two of his BC bitches would, on command, capture an
individual chicken or duck in her mouth without harming it. But he says
that many/most could not do this because it is difficult or impossible
to teach a dog how hard/gently to bite down. Some dogs in same breed
will have softer bites than others.>>

I didn't remember reading this in John Holmes' book!  I never realized that
this was unusual, since both Jenny and Jacob will do this with poultry
(although we've never tried to teach them to do it on command--they just do
it as they see it is needed).  Several years ago, we had a flock of ranging
chickens.  On several occasions we needed to round them up, and Jenny
joined in after watching us trying to catch them.  She would chase down one
bird at a time, pick it up in her mouth and bring it to us.  Once in awhile
she couldn't get a good hold on it and would just pin it to the ground with
her foot and/or her mouth so we could come get it.  Jacob now does exactly
the same thing with any of our baby birds who escape the pen.  I figured it
was common working collie behavior to do this.

Sandra