Many missing scenes are considered minor to the overall plot and were mostly removed to reduce running time. However, one scene taken from the book was removed because of its shocking content: After the hired gunman falls to his death from a steep crag from which he was attempting to shoot the dogs, a helicopter flies over the snow-covered crags and valleys, cutting to a close-up of his body, ripped to shreds, implying that the starving dogs had eaten the corpse.

Source : http://en.wikipedia.org/wiki/The_Plague_Dogs_%28film%29