420 . BLOOD DISEASES. 



corpuscles, the microbes are usually found in all the corpuscles. 

 Extravasations of blood are found in the pelves, and in most 

 cases the bladder is found to contain urine mixed with haemo- 

 globin, whilst ecchymosed spots are seen on the inner surface 

 of the mucosa. 



The digestive apparatus, with the exception of the abomasum. 

 which is frequently congested, generally presents no definite 

 alterations. The pyloric portion of the abomasum is found to 

 contain deep ragged excavations with haemorrhagic bases. The 

 constancy of these ulcers, probably the result of vascular occlu- 

 sion, is considered by Moreau Morris to be more certain indication 

 of Texas fever than any other lesions commonly present. 



The intestinal lesions are congestions and pigmentation, with 

 an increased flow of bile. 



Prevention and Treatment. — If the disease is suspected, the 

 herd should be examined thoroughly for ticks, and the animals' 

 temperature taken. The combination of ticks and fever, or the 

 jrresence of the former in a locality where they do not naturally 

 exist, may he considered a sure sign of the imminence of Texas 

 fever. If the ticks are found they should be carefully removed 

 and the cattle at once transferred to uninfected grounds. The 

 examination for ticks should be done repeatedly, and all ticks 

 destroyed. These measures may not prevent all attacks, nor 

 cut short the disease after it has once shown itself, but the 

 reporters are satisfied that fewer animals will succumb. A 

 single infection is sufficient to cause severe and prolonged 

 disease, as shown by the experimental injection of blood ; but 

 the mortality seems to be lower than in natural exposures, 

 where the infection is intensified with every additional tick. 



No special line of medical treatment has as yet been tried. 

 Quinine and its preparations are proposed as possibly valuable, 

 and methylene blue, recommended for malaria, is referred to as 

 worthy of trial. 



Inoculation with the blood of Southern cattle, apparently 

 healthy, and with that of diseased Northern cattle, transmits 

 the disease, and if this is done after the hot summer weather 

 has passed, the induced disease may be of a mild character ; 

 but it appears that immunity is not assured, as it is reported by 

 Dr. Dinwiddle that of vaccinated and non-vaccinated cattle sent 

 to Texas Q>&^ per cent, of the vaccinated and 88f of the non- 

 vaccinated died. 



