SECTION XXII. 



PARASITIC DISEASES. 



Experienced men will corroborate the state- 

 ment that more sheep are lost from invasions 

 of parasites than from all other causes com- 

 bined, with the possible exception of digestive 

 disorders. Before the days when scab was under 

 control, parasites were, even more than at pres- 

 ent, the scourge of the sheep business. 



Sheep seem to have very little power to re- 

 sist these pests, and when once infected, not only 

 succumb but spread infection among others. In 

 many instances, the vitality is so lessened by 

 parasitic invasion, that although death does not 

 result, little gain is made in weight or wool be- 

 cause of the devitalizing effect of the parasitic 

 infestation. The animal is in a fit condition to be 

 carried away by trivial diseases, that in perfect 

 health would be resisted with little trouble. 



It is of the greatest importance in this class 

 of diseases to quickly discover the inciting cause. 

 This is most vital; treatment of the infected in- 

 dividual or individuals being secondary. Stock- 

 men do not care for finely spun theories or for 

 prolonged scientific explanation of the probable 

 cause of an epizootic among their flocks ; they do 

 not appreciate the beauties of science, and care 

 little for the life-history of the pest. What they 

 most earnestly desire and are willing to pay 



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