FLUKE, OR LIVER ROT 539 



fattening them. The immediate cause of the disease 

 is the introduction into and the presence within the 

 liver of two fluke or leaf-Hke parasites, termed the Dis- 

 tomum Lanceolatum and Fasciola Hepatica, and their 

 ova, which are present in thousands, disorganising 

 the liver, preventing the secretion and excretion of 

 bile, and draining the body of its blood until it 

 becomes anaemic and generally dropsical. The ova, 

 or eggs, of these parasites are not hatched within the 

 body of the affected sheep, but pass out with the 

 dung, and unless moisture and heat are afforded they 

 come to nothing, but if they gain a pool of fresh 

 water, they are hatched, and, floating about, are on 

 the out-look for molluscs, the bodies of which they 

 pierce, and then become encysted and form brood 

 capsules, and within these many young embryos may 

 be formed. If the molluscs are swallowed by the 

 sheep in the grass or water, then the embryos develop 

 into mature flukes, inhabiting the bile ducts and re- 

 producing themselves only by eggs. One fact, how- 

 ever, is certain, namely, that where sheep are fed on 

 salt-marshes, the complaint never occurs ; and in 

 Lincolnshire sheep pastured in such localities are 

 uniformly well fed, and in most excellent condition, 

 and bring high prices. It will now be apparent to 

 the reader why high lying and dry pasture lands 

 are almost exempt from fluke disease, and low, un- 

 drained soils, where fresh water rests in pools, is 

 infested ; and, also, why salt marsh lands are exempt 

 from the malady and may lead to recovery of the 

 affected sheep, the salt being a poison to the 

 parasites. 



Remedies. — As preventative, drain the pasture 

 lands and get rid of the pools of surface water ; if 

 this cannot be accomplished dress the pastures with 



