110 THE LUNG PLAGUE OF CATTLE 



We could see through the pleura on both surfaces of the nodule a black discoloration, 

 which was irregularly distributed over the surface of the nodule and in the Inn*; t issue 

 adjoining it. The lung tissue in general and that adjoining the nodule were exam- 

 ined. The bronchial tubes were healthy up to the very margin of the nodule, but at 

 different points in the lung, and especially in the vicinity of the nodule, there were 

 small irregular areas of black discoloration surrounded by fibrous tissue, rendering the 

 portions of lung affected impervious. These appearances I attribute to hemorrhagic 

 infraction having taken place, which led to more or less alteration of the lung tissue. 

 On making a section of the nodule, it was found that the lung tissue had been mostly 

 removed by absorption, but that stretching from one side of the cavity to the other 

 were numerous bands or septa. These bands had undergone calcareous degeneration, 

 as also had the walls of the cavity, which I found to contain two flukes (Distoma he- 

 paticum). The largest of the two, when drawn out to its full size, was about two inches 

 long. There was a small quantity of a dirty brownish-looking liquid in the cavity, no 

 doubt mostly composed of the debris of the softened lung tissue. Adjoining this 

 cavity was a small one, containing a small quantity of the same kind of fluid ; but the 

 walls of this cavity were empty and it did not contain any parasites. 



This case throws somelighton the previous ones, and also on the alterations in the 

 tissue of the lung now under consideration. The wanderings of these parasites are 

 the occasion of the various morbid alterations which have been found in the lungs. 



In a seventh case examined shortly after the one above mentioned a similar cavity 

 was found in a lung which also contained two flukes (Distonea hepaticum). This case 

 appeared to be more recent, as the bauds stretching from one side of the cavity to the 

 other had only partially undergone calcareous degeneration, and were pink and soft 

 in some portions. The same remark applies to the walls of the cavity. This lung had 

 likewise some small encysted portions of tissue undergoing cheesy degeneration. 



On the 22d of October I examined the left lung of a Western animal which showed 

 red hepatizatioii extending from dorsal surface of lung downward and inward to a 

 depth of about three inches; the breadth and length of hepatized portion was about 

 three inches. Did not ascertain anything as to the history of the case or even the sex 

 of the animal. The weather was rather warm at the time of examination. 



On the 7th December I found the right lung of a Western animal affected with 

 tuberculosis. The two anterior lobes were almost entirely tuberculous, there being 

 very little sound tissue remaining in them. The lobes were nodulated and irregular, 

 and the tubercular deposit which was of a yellow color was undergoing liquefaction. 

 There was considerable thickness of fibrous tissue surrounding the lobules, which 

 formed white septa encircling the lobules. 



I have given at some length the morbid alterations produced in the lungs of the Texas 

 cattle by the invasion of the Distonea hepaticum, as I think it possible that they might 

 be mistaken for the lesions remaining after an animal has recovered from contagious 

 pleuro-piieumonia, especially when lungs are examined which do not contain the Dis- 

 tonea hepaticum. 



The case of red hepatizatioii presented less resemblance to the lesion of contagious 

 pleuro-pneumoiiia than did some of the alterations in the lungs of the Texas cattle. 

 In the case of red hepatizatioii the color was uniform, and there was 110 interlobular 

 effusion. 



The lungs of the 1,794 cattle which were raised in the State of Michigan were free 

 from disease of any kind. 



2. EXAMINATION OF STOCK-YARDS. 



TOLEDO. 



In September I went to Toledo and visited the stock-yards at East Toledo, which I 

 examined, as well as the cattle which were in them at the time. I was informed by 

 Mr. A. E. Forster that the cattle-yards cover 35 acres ; that no cattle are sold at the 

 stock-yards ; they are merely unloaded to be fed and watered, and are then reshipped 

 to continue their journey eastward. Mr. Forster had been employed at the cattle- 

 yards for eight years, and never knew of contagious disease occurring among cattle 

 in the yards or extending from the yards to cattle outside of it. 



I called on several veterinary practitioners, some of whom had practiced in Toledo 

 for a number of years ; but none of them had ever seen or heard of any cases of con- 

 tagious disease occurring among cattle in Toledo or its vicinity. I also visited the 

 pound, where stray cattle are frequently brought, and made inquiries as to the occur- 

 rence of contagious disease among cattle ; but Mr. Hiftleiu, who has charge of it, 

 answered my inquiries in the negative. I made inquiries of several other citizens of 

 Toledo, with a similar result. 



GROSSE ISLE. 



On the 20th October, visited the stock-yards at Grosse Isle, and made an examina- 

 tion of them. These stock-yards are surroimdel by a high close fence. Mr. A. Will- 



