The Rot in Sheep. 



75 



may be asked, would be the result? Why, that these infected 

 sheep, instead of becoming fat enough for slaughtering, would 

 gradually have lost flesh, and ultimately have died anaemiated, 

 even if not more than a dozen of the entozoa had originally 

 occupied their biliary ducts. 



Thus we see the necessity of becoming conversant with the 

 method of propagation of each entozoon, so as to be able to speak 

 with certainty of the ill effects attending its presence. The 

 trite remark, " Oh, a few worms do no harm," may prove true, 

 provided the parasites are inhabiting a part of the organism 

 which is comparatively of little importance to the direct main- 

 tenance of vitality, and that their number does not multiply 

 therein, and thus speedily lay the foundation for structural 

 disease. 



Much also of the ultimate mischief resulting from entozoa 

 will depend, as just stated, on the importance of the organ 

 in which they may be situated. Thus a single hydatid in the 

 brain will by its pressure produce serious disease, and ultimate 

 death of the affected animal ; while a dozen or more hydatids 

 located within the lungs, liver, or other organs, will be unre- 

 cognised during life from any pressure or irritation they may 

 produce. Facts of this description are frequently too little 

 regarded in estimating the influence of parasites on the health 

 of animals. They have, however, an important practical bear- 

 ing on the disease in question. 



Thus it will be seen that the rate of the progress, as well as 

 the duration of rot, is governed by a variety of circumstances, 

 and that many of these are so occult and changeable as to forbid 

 our predicting with any degree of certainty how long affected 

 sheep may bear up against the disease. 



With regard to the time of the manifestation of the symptoms 

 after flukes have entered the biliary ducts, it is also impossible 

 to speak with any degree of certainty. A combination of un- 

 favourable circumstances may give rise to the symptoms in five 

 or six weeks ; while, on the contrary, the majority of things 

 being favourable, even months may pass before rot is suspected 

 to exist. No hasty generalisations should ever be come to on 

 such a point as this, and more especially when an action at law 

 may hinge on the opinion which is given. A patient inquiry 

 into the history of each individual instance 4 can alone furnish 

 correct data to act upon. 



Post-mortem AprEA rances. 



The lesions to be observed Oil inspecting the body of a sheep 

 affected witli rot will vary according to the progress of the malady. 



