BILHARZIOSIS IN CATTLE AND SHEEP. 



441 



often the initial symptom. At first the urine is quite bloody, but it 

 gradually becomes clearer, and it is only at the end of micturition that 

 muco-purulent flakes are expelled, in which numerous eggs and even 

 embryos are found ; the urine contains also epithelial cells, more or 

 less pus, eggs, and occasionally embryos. On micturition sharp pains 

 are felt at the base of the penis or at the gland, possibly due to the 

 passage of eggs. The passage of eggs through the walls of the bladder 

 gives rise to cj/stitis ; blood be- 

 comes more abundant in the 

 urine after fatigue or coitus ; 

 clots may form and cause reten- 

 tion of urine ; chronic urethritis 

 may develop, evidently due to the 

 presence of the eggs. In Egypt 

 80 per cent, of the cases of vesical 

 calculus in man coincide with 

 bilharziosis ; the formation of the 

 calculi evidently results from the 

 presence of the eggs, for the cen- 

 tral nodule always contains one 

 or more of these structures. 

 Urinary fistulae, opening on the 

 perineum, more rarely into the 

 rectum, occasionally form. The 

 mucosa of the vagina, also of the 

 uterus and bladder, becomes im- 

 pregnated with calcareous salts. 

 Nephritis develops in grave cases. 



If the parasites lodge in the 

 veins of the rectum the lesions 

 caused are analogous to those 

 described for the genito-urinary 

 tract. 



The heart, lungs, and liver generally remain normal. 



Pathology. The bladder is reduced in size, while its wall is greatly 

 thickened, due chiefly to hypertrophy of the muscularis ; the mucosa 

 is also thickened, and at certain points it is indurated by uric or cal- 

 careous deposits, but the principal lesion consists in ulcerations covered 

 with sanious pus. Lesions analogous to those of the bladder are also 

 observed in the lower third of the ureters, and may extend as high as 

 the kidney ; the ureter is enlarged and tortuous ; the mucosa irregular ; 

 its lumen may remain nearly normal in size, but its wall becomes very 

 thick : the flow of urine may be obstructed ; in short, a veritable 



Fig. 208. — Eggs of bovine blood fluke 

 (Schistosoma bovis), showing the pecu- 

 liar process on the end. a, b, Layers of 

 the o\aduct ; c, eggs in the oviduct X 180 ; 

 X, eggs deformed by pressure ; y, spinous 

 process on end of egg x 700. (After 

 Sonsino.) 



