The accident is most likely to occur among cattle on very hilly pastures.
"Special Report on Diseases of Cattle"
U.S. Department of Agriculture J.R. Mohler
We had now traced with our wheels, a good way through a country much broken and shut up by sandstone gullies; but which contained also many rich valleys, and extensive hilly tracts of trap rock, on which the grass was very luxuriant, apparently available for either sheep or cattle.
"Journal of an Expedition into the Interior of Tropical Australia In Search of a Route from Sydney to the Gulf of Carpentaria (1848) by Lt. Col. Sir Thomas Livingstone Mitchell Kt. D.C.L. (1792-1855) Surveyor-General of New South Wales"
Thomas Mitchell
It must, however, be remembered that they also come from rain-water, and that in hilly or broken regions the source of that rain water may be the surface of the ground only a few hundred yards up the hill or mountain, and impurities there may affect it.
"A Handbook of Health"
Woods Hutchinson