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sheep's liver of a flat parasite, generally known as the fluke, the 

 Fasciola hepaiica of zoologists. It is shaped like a flounder, hence 

 its common name. It is of a light-brown color, changing some- 

 times to flesh-color, and ranges in si/e up to half an inch in length, 

 though specimens are sometimes found much larger. This disease 

 is known over the greater part of the earth's surface where sheep 

 are raised. In wet seasons it occasions very serious losses among 

 the European flocks. 



The life history of this parasite is now fully known, consequently 

 measures may be taken to control it. As yet no means of destroying 

 the fluke in the sheep have been discovered. The fluke deposits 

 an immense number of eggs, as many as seven millions having been 

 obtained from the gall bladder of a single sheep. The eggs are 

 voided by the sheep, and under favourable circumstances (the 

 presence of moisture) they are hatched, and the larval flukes find a 

 host in small snails. Should this host not be forthcoming the larval 

 flukes die. On quitting the intermediate host the parasite, in 

 another intermediate stage, attaches itself to the stems of grass, 

 when it is taken up by the sheep, after which it bores through the 

 internal organs to the liver, where it develops into the mature 

 fluke. 



In the case of fluke it is apparently useless to attempt a cure, 

 consequently the best thing to do is to adopt preventive measures. 

 These are draining marshy, low-lying lands, and if possible top 

 dressing with lime or salt, or both. These kill the small snails, and 

 thus cut off one link in the chain of changes the larval flukes undergo. 



With most of the internal parasites that trouble the domestic 

 animals the parents die after laying their eggs, but the fluke is an 

 exception. I know of a case in point. A number of flukey sheep 

 were brought on to a property which, though containing several 

 nasty spots, was always free from fluke. The sheep were kept on 

 the place for four years, and experiments made showed that they 

 voided lluke eggs all that time. Owing probably to the marshy 

 land being almost a lime bed there were no intermediate hosts for 

 the larval fluke, and consequently they must have died, as sound 

 sheep brought into the place did not become flukey. This shows 

 the clanger of bringing flukey sheep into sound country, as there is 

 apparently no end to the mature flukes as long as the sheep lives. 



Where the country is such that the larval flukes may develop, 

 great cure should be exercised in selecting the sheep that are 

 brought on to the place, as the flukes multiply with such nmazing 

 rapidity that one infected animal is sufficient to infest the run. 

 Various licks are recommended as preventives of lluke. Most of 

 them would improve the health of the sheep and might possibly 

 pr<>ve injurious to the fluke when first taken up with the grass. 

 One favorite lick isS Ib. sulphur to 100 Ib. Liverpool salt. The lick 

 described in another place, composed of lime, sulphate of iron and 

 salt, is excellent. Where the soil is at all favorable to the develop- 



