The Sheep-Fluke. 19 



Rotation of Stock. 



We often hear of the rotation of crops, but ahnost never of the rotation 

 of stock ; yet where it can be accomplished the rotation of stock is a very 

 good practice. By rotation of stock, I mean the pasturing on the same 

 paddock one after another different kinds of stock. Thus, sheep for a time, 

 followed by horses, and these latter followed again by bullocks. In this 

 place it is only necessary to take note of the advantages derived in decreas- 

 ing the amount of loss from fluke. 



In general each species of animal has its own particular parasites, so that 

 the parasites found in the sheep are not found in the ox, while the parasites 

 of both differ from those of the horse. There are, however, exceptions to 

 this rule. Thus the fluke is found in both the sheep and ox, as well as many 

 other animals. In such an exceptional case, nevertheless, it nearly always 

 occurs that the parasite is very much more common in one of the hosts than 

 in any of the others. As an instance of this, it may be remarked that fluke 

 is very much less common in bullocke than in sheep. In other words, the 

 sheep is the chief host of the fluke. 



It is obvious, therefore, that a paddock that has become flukey under 

 sheep may be improved by turning in stock which harbour fluke to a less 

 degree than does the sheep. Bullocks following flukey sheep will, of course, 

 pick up fluke, but fewer of these will come to maturity, and henceforth so 

 long as bullocks continue to occupy the paddock the amount of fluke-eggs 

 will diminish until the paddock would be again fairly safe for sheep. The 

 following rotation may therefore be recommended for a flukey paddock : — 



The length of time for which each kind of stock should be allowed to 

 occupy the paddock depends on the season, and more particularly on the 

 life-history of the fluke. An entire season, or even two, would be the safest 

 rule to follow, but this, of course, would in many cases be out of the ques- 

 tion. In any case the rotation should be arranged so as to bring on the 

 sheep in the dry times if possible. 



The foregoing ideas occurred also to the late Dr. Bancroft, of Brisbane 

 though whether his conception antedates mine T must leave in doubt ; for 

 while he first placed them in print in one of the Queensland newspapers, I 

 had at an earlier date also publicly expressed them. Furthermore, it is quite 

 possible, so obvious are they, that these ideas may have originated also with 

 previous writers ; but if so, the fact has escaped me, and indeed cannot, I 

 think, be well known. There can be no doubt that some form of systematic 

 rotation could be followed with advantage by many pastoralists. Even if 

 rotation is impracticable on all paddocks, it might be applied on those most 

 liable to disease. 



Of course the value of these suggestions is very much enhanced by the 

 fact that they apply to other diseases than fluke, as I shall point out in my 

 general report. 



