862 DISEASES OF CATTLE, SHEEP, GOATS, ETC. 



To calculate how much nicotine solution or extract of tobacco 

 should be used for 96 gallons of water, divide the quantity of nico- 

 tine required in the dip by the proportion of nicotine in the extract. 

 For example, suppose the nicotine solution contains 25 per cent 

 nicotine, we have 0.40-^0.25=1.6. Therefore in this case it would 

 require 1.6 pounds of nicotine solution for the 96 gallons of dip. 

 Or, if a tobacco extract is used, having for example 2.4 per cent of 

 nicotine, the formula would be as follows: 0.40^-0. 024=16. 66, 

 and therefore 16.66 pounds would be required for 96 gallons of dip. 

 Do not use any preparation the strength of which is not given on 

 the outside of the package. In preparing these dips the tobacco 

 solution and sulphur should be mixed together with water before 

 adding them to the water in the dipping vat. The dip should on 

 no account be heated above 110 F. after the nicotine solution is 

 added, as heat is liable to evaporate the nicotine and weaken 

 the dip. 



Beaumont Oil Emulsion. Directions for making 100 gallons. 

 Dissolve with the aid of heat 5 pounds of hard soap (ordinary 

 laundry soaps are satisfactory) in 5 gallons of soft water; to this 

 solution add 20 gallons of Beaumont crude petroleum or a similar 

 oil which may or may not contain sulphur, mixing with a spray 

 pump, or otherwise, in a thorough manner. To this concentrated 

 emulsion add sufficient soft water to bring the total up to 100 gal- 

 lons, keeping the whole mass thoroughly agitated. 



When properly prepared the concentrated emulsion will stand 

 indefinitely without any tendency toward a separation of the oil and 

 water, and can be diluted in any proportion with cold soft water. 



Chorioptic mange, due to a different species of mite from that 

 causing common cattle mange, is confined almost entirely to the re- 

 gion at the root of the tail and may persist for years if not treated. 

 The treatment is the same as for psoroptic mange. 



Demodectic mange, which is due to a small parasite that lives 

 in the hair follicles, causing pustules, especially on the neck arid 

 shoulders, occurs occasionally among cattle in this country and is of 

 importance on account of the injury to the hide. When tanned, 

 hides infested by this parasite are pitted, the pits, in some cases, 

 being so deep that they form holes. No practicable treatment is 

 known for this disease. 



TICKS. 



About 10 species of ticks have been reported as parasites of 

 cattle in the United States. The most common and the most im- 

 portant is the species known as Margaropus annulatus, which trans- 

 mits Texas fever. Information concerning this tick and Texas 

 fever has been given elsewhere in this volume. 



The ear tick (Ornithodoros megnini) is frequently found in 

 the ears of cattle in the western United States. 



Treatment for Ear Ticks. On account of their protected loca- 

 tion ear ticks are not affected by dipping or spraying. Ear ticks 



