1911] on Grouse Disease, 23 



the walls of the caeca become thickened, the villi, as a rule, greatly 

 hypertrophied (in other cases atrophied), and both villi and ridges 

 were embedded in the above-mentioned cementing material, and seem 

 to be composed of a mixture of mucous and granular d6bris. 

 j^umerous Strongyles were seen adhering to the mucous meml)rane, 

 and seem in places frequently to penetrate the villi. In some of the 

 most serious cases the ridges were found to resemlile masses of coral, 

 with cave-like depressions between the individual villi which fre- 

 quently cease to Ije distinguishable : from these depressions one or 

 more Strongyli protruded. In section the epithelium was seen to be 

 hypertrophied. The muscular wall suffered from an infiltration of 

 fibrous tissue. The fat which normally lies at the bases of the ridges 

 in a healthy grouse had disappeared and the blood-vessels showed 

 thickenings of their walls. The connective-tissue base of the ridges 

 is greatly increased, and the vessels and the villi were dilated and 

 probably increased in nnmlier. In most places the connective tissue 

 contained a large number of cells prolial»ly inflammatory in origin, 

 and in some cases fibroid change was taking place. The epithehum 

 was proliferated and thrown into folds. The lymphoid follicles were 

 .indistinguishable 



The general condition of a grouse suffering from Strongylosis 

 shows evidences of a chronic inflammation of the ahmentary canal 

 leading to fibrosis. The Trichostrongylus in some cases penetrates 

 to the deepest portions of the crypt. The epithelium lining these 

 depressions when the round-worm is adjacent to the walls of the 

 intestine has greatly altered, and there is a marked increase in the 

 fibrous tissue at its base. 



In fact we have, as Dr. Cobbett and Dr. Graham Smith, who have 

 so ably worked out the pathology of Strongylosis, and whose results 

 have appeared in the Journal of Hygiene, say, " a chronic inflamma- 

 tion leading to fibrosis." This portion of the alimentary canal is, in 

 vSydney Smith's words, both " vext " and "agitated." 



It thus appears that the presence of those Strongyli leads to a 

 chronic inflammation of the cteca and to fibrosis. The normal 

 functions of tliese very important organs, the cteca, are interfered 

 with and the tissue lining them is destroyed. The bird wastes away 

 and ultimately dies. But there is another factor in the case. When 

 the degree of infection surpasses 1,000 Strongyli in each caicum, 

 there is no doubt a larger increase in the Bacillus coli in the liver 

 and in the lungs and other organs. These bacilli do no harm whilst 

 free in the alimentary canal, but when they pass the mucosa and 

 reach the other tissues of the body they undoubtedly serve to set up 

 various disorders. 



But the presence of these worms, and also, I believe, to a minor 

 extent the presence of the transparent tape-worm in the duodenum, 

 has a further and indirect ill-effect on the grouse. When hand-reared 

 birds which were free from T. pergracilis were investigated, practically 



