GUAM AGEICULTUEAL EXPEEIMEKT STATION, 



27 



the time, the degree of infestation varying from a few ticks to many 

 hundreds. It has been necessary to pasture this cow in various places 

 on the station lands, and although hand picking of ticks has. been 

 practiced and repeated applications of cottonseed oil and kerosene 

 have been made ^he frequently becomes reinfested. The presence of 

 ticks in large numbers on the cow always causes a rise in tempera- 

 ture. It appears that establishment of immunity would be difficult 

 and unreliable. Instead of an immunity being established the disease 

 seems to assume a chronic form. Death may occur at any time, or 

 the animal may continue to live in an emaciated condition, with 

 anemic mucous membrane, somewhat impaired appetite, a jugular 

 pulse, and almost constant diarrhea. It is believed that imported 

 cattle, if allowed to become reinfested with ticks from time to time, 

 will die either of an acute or chronic form of the disease, or continue 

 to live indefinitely, displaying the above symptoms. 



Fig. 1. — Temperature chart of Willowmoor Red Rose. 



John Gray, the imported Ayrshire bull, has suffered several severe 

 attacks of fever due to the ticks. Prompt removal of the ticks and 

 good care at the time have left him in excellent condition. This bull 

 in the past year has been infested with ticks but once, from the lat- 

 ter part of December, 1914, to an early date in January, 1915. ki all 

 other times he has been tick free. A study of the temperature chart 

 (fig. 2) will show several slight drops and rises in his temperature 

 which were due to exposure to the sun or to chilling showers for too 

 long a period. With the exception of these slight variations and that 

 during his illness in December, his temperature has been practically 

 normal. Although this bull has been tick infested several times and 

 has suffered severe attacks of fever varying from 5 to 10 days in 

 duration, the station feels that to send him to the stock farm at 

 Cotot and allow him to run free, with no attention paid to tick 

 infestation, would result in the loss of the animal. The effect of tick 



