Common Parasites 11 



a week. It is inefficient if any ticks are allowed to develop suffi- 

 ciently to produce eggs. 



Hand-dressing. This is practical in case the herd is small. It 

 consists in removing and destroying, preferably by burning, all 

 large ticks, then applying to the cattle by means of brush or sponge, 

 some tick destroying substance such as crude petroleum, tick oil, 

 cotton seed oil and kerosene, equal parts, kerosene and lard equal 

 parts, or other tick destroying or disinfecting agents. 



Spraying consists in the use of tick destroying substances, such 

 as may be applied with a spray pump. The best and cheapest pre- 

 paration for this purpose is the arsenical solution. Other substances 

 which may be used are cotton seed oil and kerosene, solutions of 

 coal tar disinfectants and stock dips. In spraying great care must 

 be exercised that all portions of the skin are made thoroughly wet. 



Dipping is most efficient and economical where large numbers of 

 cattle are to be treated on a ranch, farm or in a community. It 

 consists in passing the cattle, every two weeks, through a vat of 

 tick destroying solution of sufficient depth that the cattle become 

 completely immersed when plunged into it. Vats are preferably 

 constructed of concrete and when once built are permanent and 

 valuable farm equipment. In addition to being valuable in tick 

 eradication, they are useful for the dipping of all kinds of farm 

 animals for the treatment of diseases such as mange of cattle, sheep, 

 hogs and dogs and for the destruction of insect pests on all kinds 

 of live stock. 



Arsenical Solution. 



This preparation has given excellent results and is probably the 

 most economical agent for destroying ticks and may be used in 

 spray pump or dipping vat. The formula is as follows: 



Sodium carbonate (sal soda) 24 pounds. 



Arsenic trioxid (white arsenic) 8 pounds. 



Pine tar 1 gallon 



Water sufficient to make 50 gallons. 



Preparation of Arsenical Solution. 



A large tank or caldron to which heat may be applied either by 

 fire or a jet of steam is necessary. Bring to a boil twenty-five gal- 

 lons of water. Add the sal soda and stir until dissolved. Add 

 the arsenic and again stir until dissolved. Allow the solution to 

 cool to 140 degrees Fahrenheit. 



Dissolve 1 pound concentrated lye in one quart of water and stir 

 into the pine tar, then add the tar slowly in a thin stream to the 

 solution of soda and arsenic. Stir thoroughly and increase to 50 

 gallons by the addition of water. This is known as "stock" solu- 

 tion and is not ready for use until it has been reduced in strength 

 by adding nine gallons of water to each gallon of "stock" solution. 



