We are finally butchering some hens that don't seem to be laying very well.  This is a great challenge for a variety of reasons.  For one it isn't quite as straight-forward as it might seem to tell which hens are "spent".  There are signs of course.  There's the comb which appears anemic rather than the beautiful, lusty red of a top layer.  Then there's the vent, which can appear moist and rather open (good) or dry and somewhat pinched