Long ago - not sure how long ago - shepherds who cared for large flocks of sheep on the upper moorland of Wensleydale and Swaledale had their own special method of checking them. If you read Dreadnought's blog you will know that he counts the sheep under his care every day. It is a wise move because if a sheep CAN find a way out it WILL!
Sheep on the upper moorlands would be collected in maybe twice a year - once for "tupping" in the late Autumn, to produce lambs in late Spring, and maybe once for a check on feet, worms etc, and to be shorn. These flocks were often hundreds so shepherds devised their own method to count them.
Here is how he counted the first twenty:
Yan, Tan, Tethera, Methera, Pimp, Sethera, Lethera, Hovera, Dovera, Dik(10)
Yan Dik, Tan Dik, Tethera Dik, Methera Dik, Bumfit (15), Yan Bumfit, Tan Bumfit, Tethera Bumfit, Methera Bumfit, Jigget (20).
When the shepherd got to twenty he would raise his index finger and start again. When he had all five fingers up it would mean he had got to 5x20, or one hundred. Then he would put a stone in his pocket and start again.
Although it sounds complicated, when you think about counting up to large numbers it was probably the easiest way (although why they didn't use the words one to twenty I don't know - probably something to do with local dialect).
I think the method died out during the early twentieth century. There are still a few shepherd's bothies around, where the shepherd would live, high on the moorland, during lambing time. Often now the sheep are brought in to lamb - or if they are left out the farmer can easily nip round them on his quad bike. Like all other aspects of farming, the really hard graft has been taken out of it. All that they really need now is a way of stopping cows doing great heaps of poo which needs cleaning up daily when they are indoors. (Sorry - I didn't intend to mention poo again on my blog. The trouble is that in Winter, with lots of stock indoors, it does become a fairly major preoccupation.)