266 THE GROUSE IN HEALTH AND IN DISEASE 



heather is that the stock will be better distributed over the 

 moor, and there will be less danger of their crowding into 

 small feeding areas and fouling the ground. 



No other method than heather-burning has yet been devised 

 for the destruction of the coccidian cysts as they lie upon the 

 moor, although many strong chemical substances may destroy 

 the oocysts, their application to Grouse moors is not practicable. 



The following is a summary of the effects of certain 

 reagents : 



Salt produces plasmolysis in time ; but the process is 

 rather slow, and the salt is too readily dissolved in dew and 

 rain, and so merely soaks into the soil. 



Quicklime destroys the oocysts and sporocysts. It also 

 causes the faeces to cake, thereby preventing scattering of the 

 spores. It is somewhat doubtful whether lime could be applied 

 on a large scale. Where the area of infection is small, as in 

 rearing pens, the application of lime to the soil is of service. 

 Small quantities of lime dressing are not detrimental to heather. 



Gas Lime and Slaked Lime also are useful, but each is open 

 to the same objection as quicklime. Lime in one form or another 

 certainly seems to have the best and most rapid action on 

 coccidian oocysts of any reagent that has been tried. 



Salicylates. Salicylic acid and sodium salicylate act rather 

 slowly on coccidian oocysts. Faeces mixed with them remain 

 fluid for a longer period than they otherwise would. The 

 oocysts become wrinkled and ultimately destroyed, but the 

 contents take longer to degenerate than when lime is 

 used. 



Ferrous Sulphate. Copperas or green vitriol is useful to 

 some extent in destroying coccidian oocysts, but like salicylates 

 it is somewhat slow in action. A dusting of ferrous sulphate 

 on the moors would probably be beneficial, for the iron present 

 in combination might be taken up in small quantities by Grouse 

 and, by acting as a general tonic, might better enable the 

 birds to resist Coccidiosis if they became attacked. Ferrous 

 sulphate in the proportion of 10 grains to the gallon of drinking- 



