710 Journal of Agriculture, Victoria. [10 Dec, 1917. 



stock — (1) the jjrice of a single dose iu France is sixpence, and five doses 

 must be given; (2) the drenching of a mob of some hundreds of sheep 

 every day for five days would be a task that could not be undertaken by 

 the majority of oviners, and (3) fatal results are, on occasion, attribu- 

 table to its administration. 



Preventive measures are, hov(fever, possible, and it is to this line of 

 treatment we must look for relief. One of the surest ways to open the 

 animal system to invasion of any parasite is to reduce the condition and 

 lower the vitality. Sheep that are of robust constitution will fight 

 against the invasion and withstand the effects of fluke to a far higher 

 degree than those weakened by poverty and bad management. This fact 

 should be borne in mind, a.nd, whenever possible, debilitated animals- 

 kept away from paddocks known to be " fluky." 



The constitution of all sheep should be built up and their systems 

 put into a condition capable of withstanding invasion. Experience has 

 showai that this maj^ be effected by providing licks, of which a large 

 number are on the market. One which has proved very efficacious is 

 composed of lime and salt, 20 parts each; superphosphate and sulphate 

 of iron, 5 parts each. Another is simply salt worked into a sticky mass 

 with Stockholm tar (about 1 pint to 1 cwt.) Any lick used should be 

 placed in shallow troughs protected from the weather, and easily access- 

 ible to the sheep. There is no doubt that, in addition to any improve- 

 ments the use of licks may have on the constitutions of a flock, the salts 

 will have a destructive influence upon the encysted Cercari^ when taken 

 into the stomach. 



Study of the life history of the parasite reveals another and equally 

 important channel in which to attack the problem. It is absolutely 

 necessary, in order that the various stages of development may be passed 

 through, for the intermediary host — the small fresh-water snail — to b& 

 present. Fluke cannot be transmitted from sheep to sheep. There- 

 fore, if we can break the life cycle at any point, infection will be checked. 

 And this, perhaps, can be done most effectively by freeing paddocks from 

 stagnant water and by the destruction of the snail host. 



Fluke is practically unknovsai on high lands with good natural drain- 

 age, whilst on low-lying, wet flats it is impossible, in many cases, to rear 

 sheep. The first method of attack is, therefore, revealed by nature ; 

 provide sufficient drainage and remove all stagnant water. This will 

 mean that there will be a greater chance for the destniction of the egg in 

 the first place, and a lessened chance of entrance to the snail host, the 

 number of which will also be reduced on well-drained land. Then keep 

 the pasture on low-lying land as free from harbors for the snail as pos- 

 sible ; destroy old tussocks and the like; top dress the pasture to encour- 

 age a growth of succulent herbage, which will be kept well cropped by the 

 stock. A heavy dressing of lime will have a very beneficial eiTect in 

 stimiilating the grass, and will also destroy large numbers of the snail. 

 A top dressing of salt has even been used in some cases, but if it be used 

 to excess it will have a deleterious effect upon the grasses. 



To summarize, all our present knowledge points to the following line 

 of treatment : — 



Drain the pastures. 



Keep sheep off pasture with water lying about. 



Destroy the snail. 



Build lip the constitution of the sheep. 



