OCR Text |
Show 1884.] DISEASES OF CARNIVOROUS MAMMALS. 183 If sections of a lung, which has been compressed by fluid in the pleura for some considerable time, say six weeks, be examined by the microscope, the following appearances will be noted :- The pleural covering is very thick, its surface being coated over by a thick layer of organized lymph varying in thickness according to the length of time the disease has existed. From the deeper layers of the pleura there is an invasion of fibrous tissue into the lung-substance, destroying the air-cells immediately subjacent to the original serous covering. Beneath these disorganized air-cells, a considerable tract of airless tissue exists in which the cell-walls are in apposition, and lie folded together as neatly as a lady's fan. These cells, if inflated during life, would again become functional. Approaching the main bronchus, curious changes may be seen ; here and there whole tracts of the lung-tissue are in a state of complete disorganization, others are seen with their opposite walls simply in contact, whereas in many parts the air-cells are so dilated that they present all the characters of emphysematous lung, so extreme is the distension of the air-vesicles and so attenuated their walls. Although the lung is apparently in a condition of extreme atelectasis, yet in parts, paradoxical as it may seem, we have to do also with a condition of emphysema and dilated bronchi. The Organs of Circulation. Few and far between are cases of diseases of the heart and bloodvessels in carnivorous animals. Once only have I seen pericarditis, and that was in a Coati. The disease was caused by the extension of inflammation from old-standing double pleurisy. Valvular disease was seen in an Esquimaux Dog aged at least twelve years. The endocardium was thickened and opaque, the mitral and aortic valves presented vegetations on their free borders, some of which had evidently been detached by the circulating current, as three old infarctions in the liver bore indisputable testimony. Atheroma was encountered twice, once in the aortic arch of a Dog; the remaining instance occurred in a Coati, in which the whole of the descending aorta was affected, some of the patches being of considerable size. The Alimentary Canal. Affections of the digestive tract are uncommon. Typhoid ulceration of the ilium and colon has been twice noted in the course of m y dissections. The symptoms during life were such as to lead one to suspect the nature of the malady, diarrhoea and haemorrhage from the bowel with similar cases turning up among other animals. The two cases mentioned occurred in a Tiger and a Leopard, about the same time as the cases referred to in m y paper on Diseases of Monkeys. Several Bears have died from enteritis, and in one a perirectal abscess attained to a considerable size, then burst into the peritoneal cavity, giving rise to intense and fatal inflammation. The abscess was in all probability caused by a piece of bone passing through the |