TEXAS FEVER. 



1-15 



black. The red color is merely coloring matter from the red 

 corpuscles which are rapidly destroyed by the germs. At first 

 the bowels are constipated, but later diarrhoea is not uncommon. 

 The mucous membranes are visually pale and sometimes slightly 

 yellow. As death approaches and the symptoms become aggra- 

 vated the animal usually remains down. Occasional periods of 

 excitement or even convulsions may occur. 



History of the case. — The most important factor in determin- 

 ing the diagnosis, next to finding the germs in the blood, is the 



history of the animal and the pres- 

 ence of ticks. If the animal has not 

 previouslv been exposed to tick in- 

 festation and has recently changed 

 location, or if tick infestation has in 

 any way been rendered possible, a 

 searching examination should be 

 made to ascertain whether ticks are 

 really on its body. 



Ticks where found. — The ticks 

 are most likely to be found on the 

 tender parts of the skin, such as be- 

 tween the hind legs, on the escutch- 

 eon, on the inside of the elbows, or 

 on the brisket which is most ex- 

 posed. Since the disease may de- 

 fig. 56. texas fever tick. ve j op w ithin ten days after ticks at- 



(PETTIT ) ' ■ 



Female engorged. BoapMUs i.ovi, tack the animal, and this time is not 

 <EiIey) - sufficient for them to become larger 



than twice the size of a pin head it 

 will be readily appreciated that to find the ticks is not always an 

 easy matter, especially if they are not numerous. Other diseases 

 producing blood colored urine are extremely rare among cattle in 

 this country. 



Conclusion. — The presence of the symptoms described may 

 therefore be considered as diagnostic, and good evidence as to 

 the presence of ticks even though these may not be found. 



Post mortem appearances. -Only in animals that die during 

 an acute attack are the changes well marked and of those only 

 the more pronounced will be given. Other changes may be seen 

 but they are often only slight, or absent. 



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