150 THE GROUSE IN HEALTH AND IN DISEASE 



The Committee is of opinion : (1) That the sickness which has in the past 

 caused "Grouse Disease" among the great majority of adult birds is a single 

 ^disease with clearly defined characteristics of its own ; (2) and (3) it follows that 

 if the two forms of " Grouse Disease " hitherto described as distinct diseases are, 

 in fact, one and the same disease, there is no longer any need to differentiate 

 between them; (4) that "Grouse Disease" is not due to an acute infectious 

 pneumonia caused by the presence in the lung of Klein's Bacillus; (5) that 

 adult " Grouse Disease " is caused by the presence of Cobbold's Trichostrongylus 

 in large numbers in the cseca ; (6) that another form of disease in Grouse exists 

 which has hitherto escaped notice. This disease is caused by the presence of 

 JEimeria (Coccidium) avium in the alimentary tract, and is referred to in the 

 Report by the name of " Coccidiosis." It is improbable that Coccidiosis can 

 have been responsible for any of the outbreaks of so-called " Grouse Disease " 

 in the past, for, so far as the Committee's experience extends, it is only the 

 chicks that succumb to this disease, whereas the records of "Grouse Disease" 

 refer only to mortality among adult birds. 



The grounds on which the foregoing conclusions are based form the subject 

 of chapter ix. ; chapter x. is devoted to a description of the Trichostrongylus 

 pergracilis of Cobbold, the primary cause of "Grouse Disease" proper, and 

 chapter xi. deals with the Coccidium avium and Coccidiosis in relation to 

 young Grouse. 



We have still to discuss the less important diseases of Grouse, of which 



quite a considerable list may be given ; though their interest is greater from 



a purely academic point of view than as a serious menace to the 



Minor dis- ; / 



eases of well-being ol a moor: indeed with one or two possible exceptions, 

 there is not much probability that they will ever give cause for 

 much anxiety. The exceptions occur most commonly in consequence of the 

 proximity of Grouse moors in certain districts to low-ground shootings heavily 

 stocked with Pheasants and Partridges. It is well known that these latter 

 birds are often the victims of various forms of Enteritis, and cases have been 

 reported to the Committee of Grouse dying of disease apparently contracted 

 from Pheasants which have strayed on to the moor. 



Amongst other causes of death may be mentioned diseases connected 

 with the reproductive functions, diseases connected with the seasonal moults 

 and diseases caused by deficient or unwholesome diet. 



But apart altogether from mortality due to disease, a large number of 



