DISEASES OF THE DIGESTIVE ORGANS. 55 



THE FLUKE DISEASE. 



The fluke, or Fasciola hepatica, is a parasite which infests the biliary 

 ducts of the liver. It varies iu size from an inch to a little over an inch 

 in length and has a brownish flattened body. It belongs to the group 

 of trematoda, or sucking worms. The fluke passes through several dif- 

 ferent stages of development before it reaches the livers of the animals 

 which it infests, and it is not only found in cattle, but in sheep and 

 several species of wild animals. Parasites which have attained their 

 full development usually after a time pass out of the animals which 

 harbor them and die, when they have attained the limit of their exist- 

 ence. It has been estimated that after the death and decomposition of 

 a full-grown fluke upwards of 40,000 eggs will be liberated from its 

 uterus. The agency of winds, rains, insects, the feet of cattle and 

 other animals, disperse and carry these ova to considerable distances, 

 so that a large proportion of tbem find their way to pools, ditches, and 

 streams, where the conditions exist necessary to their future develop- 

 ment. After a time they reach that stage in which they are transferred 

 with the fodder or drink to the digestive organs of their host. From 

 the foregoing statement it will readily be understood that this disease 

 prevails on low swampy laud, and especially on land which is subject 

 to inundation. During a wet, rainy season the area over which it 

 extends becomes much wider, and the losses which the disease occa- 

 sions are consequently greater. 



Symptoms. The presence of these parasites in the biliary ducts does 

 not at first appear to impair the animal's health; indeed, it has been 

 stated that for a short time the animals appear to thrive better. This 

 is accounted for by the statement that the presence of the flukes in 

 the biliary ducts stimulates the secretion of bile, that this occasions a 

 more complete digestion of the fatty elements of the food, and a con- 

 sequent improvement in the animal's condition in the early stage of the 

 disease. When the flukes attain their full size, however, and are pres- 

 ent in large numbers, they set up inflammation in the walls of the bil- 

 iary ducts. As a result of the presence of those parasites the liver 

 becomes indurated and its secreting structure becomes atrophied or 

 wasted. The affected animals become dull and weak; swellings of a 

 dropsical nature form between the jaws and along the throat. There 

 are fever, great emaciation, and dropsical accumulations in the chest 

 and belly, which are soon followed by death. 



Treatment i of no avail. Affected animals should be killed at an 

 early stage of the disease. 



SPLENITIS INFLAMMATION OF TILE SPLEEN. 



With few exceptions veterinarians agreo that the recognition of dis- 

 6>n affecting the spleen is rarely made during life, unless in the case 

 of certain febrile and contagious diseases, in which the spleen is known 



