EUSTRONGYLID^ 



297 



The eggs are 64-68 microns in length by 40-44 microns in width. 

 They are brownish in color and have numerous round depressions on 

 their surface. The}^ develop in a moist medium. 



The embryos are tapering at the extremities and about 240 microns 

 in length by 40 microns in breadth. They have a 

 great vitalitj^ and may survive within the eggs for 

 a year or more. 



Attempts at direct infection have been unsuc- 

 cessful. An intermediate host is evidently re- 

 quired, and the fact that the worm is found para- 

 sitic in the seal and otter points to the probability 

 that it lives a portion of its life in a fish. 



The eustrongyle is much more frequent in Car- 

 nivora, especially the dog, than in other animals, 

 but it is rareh' met with. In the Journal of the 

 American Veterinary Medical Association, June, 

 1917, Hall states that from Riley's and his own 

 record of cases reported it appears that this worm 

 has been found at least forty or fifty times in the 

 United States. How and in what form it finds its 

 wa}^ into the body of its host is not known. It is 

 most frequentl}^ found in the pelvis of the kidney 

 where it grows to an enormous size, producing a 

 purulent inflammation from which destruction of 

 the renal tissue follows. Eventually the kidney 

 becomes a mere thick-walled cyst containing a 

 bloody purulent material within which the worm 

 is coiled up. But one kidney is invaded, usually- 

 by a single worm, though in rare cases two have 

 been found in the kidney pelvis. The uninfestcd 

 kidney is usually found to have undergone a com- 

 pensatory hypertrophy. The worm has been 

 met with in other parts of the urinary organs, as 

 in a part or the whole of the lu'eter and in the 

 bladder. Where it is found outside of the urinary 

 organs, as in the peritoneal cavity', it is probable 

 that it did not reach such location until after 

 primary development in the urinary passages. 



Symptoms. — The symptoms are not characteristic and in some cases 

 may not be observed. Horses and cattle especially are said to show 

 little disturbance from the presence of the worm, while dogs, on the 

 other hand, suffer severe pain, are restless, and sometimes exhibit a 

 lateral curvature of the vertebral column, the concavity corresponding 

 to the affected side. ^Nlicturation may be painful and with effort, and 



Fig. 1.59.— Diocto- 

 phyme renale; male, — 

 natural size (after Rail- 

 liet). 



