From another site.(Mysongbook)

"Braxy is a bacterial infection of sheep, and in those days usually fatal. But it did not affect the flesh, and since only the best and fattest sheep were struck down, to find a newly dead braxy sheep was a find indeed, and a great help to the diet of the lucky family. [It] was said by the pundits that, on finding a dead sheep, the finder should grasp it firmly by the hind legs and swing it round his head. If the legs withstood six full circles, then the sheep was fit to eat. Be that as it may, there is no doubt that a promptly-found braxy sheep was 'wholesome fairin'. Any over-ripe specimens were inclined to stop the breath, but no more so than 'hung' pheasants or grouse, which left a mound of squirming maggots on the larder floor. (Archie Cameron, Bare Feet and Tackety Boots. A Boyhood on Rhum. Luath Press, Barr, p 73)"