254 THE TtROUSE IN HEALTH AND IN DISEASE 



In every instance I most carefully compared the results obtained experimentally 

 with the cases of natural Coccidiosis in Grouse chicks that I investio-ated on one of 

 Lord Lovat's moors in Inverness-shire, and in other cases obtained from Perthshire, 

 Dumfriesshire and Yorkshire. 



Some authors have given the name Coccidimn cunicidi ^ to the parasite of birds, 

 thereby identifying the Coccidium of birds with that of rabbits. Having had the 

 opportunity of obtaining fresh material from rabbits dying rapidly of acute 

 Coccidiosis, I fed a healthy young pigeon directly with oocysts of C. cuniculi. At 

 first oocysts were voided by the pigeon, then none were found in tlie fteces, nnd no 

 symptom associated with Coccidiosis appeared at any time. The first 0()cysts voided 

 were merely those supplied to the bird which had passed unchanged through its 

 alimentary tract. Though this pigeon received several doses of the oocysts of 

 Eimeria (Coccidium) cuniculi, it never developed Coccidiosis, and the post-mortem 

 examination made immediately after killing the bird .showed a perfectly normal 

 condition of every organ. I consider that these experiments show conclusively that 

 E. avium and E. eunieuli are distinct species of Eimeria and are not identical. 

 There are also morphological differences between the two, chiefly of size {E. avinni 

 is the smaller). 



III. Symptoms of Coccidiosis. 



The symptoms of Grouse suffering from natural Coccidiosis and those of Grouse, 

 fowl chicks, and pigeons, in which the disease has been artificially induced, are 

 identical. The symptoms that have been noted in the case of the birds examined 

 may now be stated. 



Chicks after ingesting coccidian oocysts become far less active in their move- 

 ments as a rule. The first noticeable feature is the drooping of their wings and a 

 habit of constantly looking downwards. The birds stand about more than normal 

 birds, and their calls are more plaintive. 



While fowl chicks and pigeons appear to mope, their appetite is increased, and 

 chicks experimentally infected with Coccidiosis eat far more greedily than the 

 control birds. They also drink considerably more. In spite of the increase in the 

 amount of food consumed, the birds rapidly get thinner, the muscles of the breast 

 and legs showing this to a marked degree. Throughout the progress of the disease 

 the growth of the affected birds is much retarded. 



It was necessary to feed infected young pigeons by hand, for even when they 



' The correct nairn' of this parasite is Eimeria stieda: Liudeiiiaiin. 



