It should not be necessary for me to urge upon him who owns sheep the importance of ridding his flock of ticks or other parasitic insects that annoy them. There seems to be a common but mistaken opinion that only poor unprofitable animals will get “lousy.” There are many insects, those that feed upon plants as well as animals, that seem to have decided individual preferences. It is not uncommon to see a tree or plant seriously injured year after year by some insect that does little or no harm to other trees or plants of the same species growing near. The same is true in the case of animal parasites. Certain individuals in a flock or herd, on account of a tender skin, or other peculiarities are preferred by the ticks or lice, as the case may be, and in consequence, they congregate upon these animals in large numbers, constantly, biting them and sucking their blood, causing them to become poor even with the best of care. The first step necessary to be taken to get such an animal in good condition is to free it of parasites. This can be so cheaply and easily done by the use of kerosene emulsion, a mixture of kerosene, soap and water, substances that are always at hand, that it seems entirely inexcusable for a man to allow his domestic animals and his pocket book as well to suffer from these causes.
I have already shown by experiments (See Bull. 5 and 7 of this station) that kerosene emulsion is a most cheap, effectual and desirable remedy for the destruction of lice that infest cattle and hogs. During the past summer I was enabled through the kindness of Professor L. P. Smith, who allowed me to experiment with the sheep upon the State Farm, to test kerosene emulsion as a sheep dip. It has been customary each year just after shearing to treat the sheep upon the farm with one of the standard sheep dips sold upon the market, so the sheep were very free from ticks. But as there can be no doubt as to the power of the emulsion to kill the ticks, it was thought to be well worth while to determine whether or not it could be safely applied to sheep as well as to cattle and hogs for the destruction of parasites.* Forty large full-blooded Shropshire sheep and eighteen early lambs were treated. The applications were made June 23, at which time the wool upon the sheep was a half inch and the wool upon the lambs fully one and one-half inches in length. These conditions made the test a severe one, as the chances of removing the fleece or otherwise injuring the sheep were far greater than if the treatment had been made at shearing time. The emulsion was also made strong, eight per cent, of the whole being kerosene. This is probably twice as strong as is necessary to kill ticks on sheep.
Gillette, C. P.
"Kerosene emulsion as a sheep dip and as a destroyer of parasites upon domestic animals,"
Bulletin: Vol. 1
, Article 7.
Available at: https://lib.dr.iastate.edu/bulletin/vol1/iss11/7