10 July, 1918.] Diseases of Sheep. 411 



are converted into harmless substances by other juices formed by the 

 body. Think for a moment of the effect of stopping the formation 

 of such antidotal substances. The poison would have full power to 

 exert its influence, and if death itself did not actually result, ill-health 

 or disease would certainly follow. In much the same way nature pro- 

 vides that poisons, in the shape of disease-producing germs, introduced 

 from without, shall be fought against by the system up to what might 

 be termed the breaking point. If the poison is in too large a quantity, 

 or the fighting agency is reduced in power, then the breaking point 

 is reached, disease develops, and symptoms become manifest. The 

 agents in the body engaged in this fight are the white blood corpuscles. 

 It is, therefore, evident that these must be kept up to full fighting 

 strength if success is to be looked for. Now, these corpuscles are 

 formed in the body from substances taken into the system by means 

 of the food, or, at least, their vitality is maintained by the supply of 

 proper nourishment to them. We, therefore, see that if the whole 

 body is to attain its greatest efficiency, it is necessary to supply proper 

 food. 



"We know from experience that some parts of the State are more 

 suitable for stock than others; that certain classes of stock will thrive 

 in parts where other classes fail. Along the coast bone diseases are 

 common. Some districts show heavy mortality annually (in cattle par- 

 ticularly) from impaction and so on. It is not merely a question of 

 quantity of feed, but it is essentially one of quality. Provided the 

 quality be maintained, the living machine is kept working at full 

 efficiency, and it requires a considerable amount of disturbing influence 

 to seriously upset the equilibrium. If you are using bad oil in your 

 engine you know that you cannot obtain full power, and very little 

 extra friction or work will stop the machine. If you are using bad 

 fuel in the living machine it too will perform its functions badly. 

 The reserve force or vitality of the animal is impaired, and the system 

 is exposed to the influence of any of the injurious substances — of 

 which there are so many — ever ready to operate to the detriment of 

 health. 



It is, therefore, evident that the vitality of the animal must be 

 maintained at its highest pitch. Now, unfortunately, vitality cannot 

 be measured; indeed, it is hard to describe. Many are under the 

 impression that provided an animal is fat it is healthy. This, how- 

 ever, is not necessarily so. Many an animal in good condition has a 

 very low vitality. There are some ailments^and fluke in sheep may 

 be taken as an example — in which the earliest) effect of invasion is 

 to cause the animal to lay on fat, yet its vitality is lowered. Another 

 condition is seen in ewes, particularly crossbred ones, carrying twin 

 lambs.. They are fat, yet death is common, mainly because the vitality 

 is lowered, and they are ready victims to the influence of poisons 

 produced within the body. 



The soils of Victoria generally are deficient in salts of various 

 forms, and manures are necessary to attain maximum yields of crops. 

 We know that stock in certain districts are fond of chewing bones, 

 eating bark, licking paint; if they are taken to the sea from inland 

 they lick the sand or drink sea water. All this indicates that the 



