TEXAS FEVER. 501 



At the other end of this tubing is a needle and in the middle is a T 

 joint with a syringe at the stem, of the T. By the use of valves at 

 this joint the withdrawal of the syringe piston pulls the blood from 

 the bottle, and the insertion of the piston with closure of the opposite 

 valve ejects the blood from the needle. The citrated blood is inocu- 

 lated under the disinfected skin of the animals to be immunized, as 

 in the first method. This blood may be kept in a dark, cool place 

 for one or more months without deteriorating and may be shipped to 

 other points for use. 



The i^lace where this injection is made is immaterial, but for con- 

 venience a point just behind the shoulder is usually chosen. The dose 

 and number of injections vary with the individual animals. "When 

 a large number of cattle are to be inoculated a special form of syringe 

 devised by Pound, of Queensland, may be used. The syringe is so 

 arranged by means of tubes and valves, that by simply pulling out 

 the piston of the syringe and pushing it in again the correct amount 

 of blood is drawn up from the bottle and injected through the needle 

 into the animal, thus obviating the necessity of continually filling the 

 syringe and measuring out the dose. 



As a rule it maybe stated that 1 cubic centimeter should be injected 

 into an old animal coming into the infested district, 2 cubic centi- 

 meters for a 2-year-old, and 3 cubic centimeters for an animal 9 to 

 15 months old. It will be observed that, unlike the usual custom of 

 applying treatment, the older animals take less than the young ones, 

 owing to their greater susceptibility to the disease. When an animal 

 has reacted well to a first injection and shows a very high tempera- 

 ture, great reduction of red blood cells, or other symptoms indicative 

 of reaction, it will not be necessary to repeat the injection, but in those 

 cases in which the reaction is slight, a second injection should follow 

 after an interval of 40 days, and, if need be, a third injection after 

 a similar lapse of time, always increasing the size of dose 50 per 

 cent. A thermometer, to indicate the course and severity of the 

 disease, is indispensable in this work. Usually, after 3 to 10 days, 

 sometimes longer, the inoculated animals show a mild type of Texas 

 fever, which runs a course of from 6 to 8 days and is followed in 

 about 30 days after the injection with a second attack of a milder 

 character than the first. After 40 days, when the animal has entirely 

 recovered from the inoculation, a second injection may be given 

 to increase its immunity. In some cases a very severe type of fever 

 follows the first inoculation, requiring careful nursing and treatment, 

 as suggested above. A second, milder attack follows usually in about 

 30 to 40 days, after which the animal need have no further inocula- 

 tions. It is advisable to prevent any ticks from getting on the cattle 

 until 60 days after their inoculation or until they have fully recov- 

 ered, at which time a few ticks may be placed upon them in order to 



