22 



ROT IN SHEEP. 



Fig. a. Adult Liver Fluke, b. Water Snail {Limnaea truncatula). Nat. size. 



The disease known as Rot, Liver Fluke, Coathe, and Bane, in 

 sheep, has existed in Great Britain for very many years, and 

 has caused greater losses in this country than any other disease 

 affecting this particular class of animal. In a pamphlet written 

 for the Royal Agricultural Society by Professor Simonds in the 

 year 1880, on the subject of the nature, cause, treatment, and 

 prevention of rot, he mentions outbreaks having occurred in the 

 years 1735, '47, '66, '92, and again in 1809, '16, '24, '30, '53, '60, 

 '62, and '79. The outbreak of 1879 continued into the year 

 1880, and in the statistics prepared by the Board of Trade for 

 1 88 1 there was a falling off in the number of sheep in Great 

 Britain of no less than three and a half millions compared with 

 that given for 1879. This decrease was reported to be mainly 

 due to the prevalence of rot, the greatest losses having occurred 

 in England, and Scotland being but little affected. 



Life History of the Liver Fluke. 



The common liver fluke (Fasciola hepatica) is found in the 

 biliary passages of the livers of sheep, where it produces many 

 thousands of egg's, which find their way along the bile duct into 

 the intestines and are expelled with the dung. Those which 

 fall upon dry soil may remain dormant for months, but how long 

 they may retain their vitality is not known ; whilst those which 

 reach the water in pools and dykes are at once hatched, and a 

 free swimming ciliated embryo is produced. This little organism 



