INFECTIOUS DISEASES OF CATTLE. 475 



Smearing or spraying cattle wiih a disinfecting solution. — Greasing 

 the legs and sides of cattle with cotton-seed oil, fish oil, or Beaumont 

 crude petroleum will assist in preventing the ticks from crawling up 

 on the body. In small herds, smearing the cattle with a mixture of 1 

 gallon of kerosene, 1 gallon of cotton-seed oil, and 1 pound of sulphur, 

 or with a mixture composed of equal parts of cotton-seed oil and 

 crude petroleum, or with Beaumont crude oil alone, has proved effi- 

 cacious when applied to the skin two or three times weekly during 

 the tick season. For this purpose sponges, syringes, brushes, mops, 

 or brooms may be used. This method not only kills the older ticks 

 on the cattle by mechanically plugging up their breathing pores, but 

 also makes the legs so slippery that the seed ticks are unable to get a 

 foothold in order to crawl up on the cattle. Where a large number 

 of animals are to be treated, but not sufficient to make it advisable to 

 construct a dipping vat, spraying the infested animals has given very 

 favorable results. The animals should be placed in a chute or a stall, 

 or tied to a tree, and then sprayed with Beaumont oil or a 5 per cent 

 solution of any of the standard coal-tar dips. The solution may be 

 applied by means of a force pump, such as is used by orchardists to 

 spray fruit trees, or by placing the solution in a barrel upon a wagon 

 or on a platform above the animals and allowing the fluid to gravi- 

 tate through a hose, to the end of which is attached an ordinary 

 sprinkling nozzle. The solution is then allowed to flow over the skin 

 of the animal, especially upon the legs and under portions of the 

 body. If the cattle are on tick -infested pastures, this treatment — 

 either smearing or spraying — must be continued through the whole 

 season, and if thoroughly done it will leave the fields free from ticks 

 the following year. 



Dipping in a vat. — Many efforts have been made to discover a 

 practical method for dipping cattle to destroy ticks without injury to 

 the cattle, and the bureau has experimented for years with this object 

 in view. Numerous kinds of dips have been used and many failures 

 have been recorded, but apparently a successful one has been found in 

 the crude oil — so-called Beaumont oil — obtained from certain Texas 

 wells. This oil has now been used on a rather large scale, and it has 

 been very successful in killing ticks without at the same time mate- 

 rially affecting the health of the cattle when the proper precautions 

 have been observed. In fact, it is distinctly superior to any of the other 

 dips that have been tested. In these experiments it was found that a 

 light oil heavily charged with sulphur is the most desirable for 

 dipping cattle, as the heavy oils injure the animals dipped in them. 

 An oil with 40 per cent of its bulk capable of boiling between 200° 

 and 300° C, having a specific gravity between 22^° and 24£° Beaume, 

 and containing 1£ to l£ per cent of sulphur is most desirable, and 

 these requirements should be stipulated before purchase. In a recent 

 dipping of 57,000 head of cattle on the Kansas and Osage Indian 



