422 DISEASES OF THE HORSE. 



Pure chronic inflammation of the laminae is not very commonly met 

 with, but is most frequent in horses that have long done fast track 

 work. They have " fever in the feet " at all times and are continually 

 sore, both conditions being aggravated by work. Like chronic in- 

 flammation of other parts, there is a strong tendency to the develop- 

 ment of new connective tissue, which, by its pressure upon the blood 

 vessels, interferes with nutrition. Wasting of the coffin bone and in- 

 flammation of its covering with caries is not unusual. The continued 

 fever and impaired function of secretion result in the production of 

 a horn deficient in elasticity, somewhat spongy in character, and in- 

 clined to crumble. In some cases of " soreness " in horses used to 

 hard or fast work, there is evident weakness of the coats of the ves- 

 sels, brought on by repeated functional exhaustion. Here slight work 

 brings on congestion, which results in serous effusion and temporary 

 symptoms similar to those of chronic laminitis. 



Complications. — Complications concurrent with or supervening 

 upon laminitis are frequent and varied, and are often dependent upon 

 causes not fully understood. 



Excessive purgation is one of the simplest of these, and not usually 

 attended with dangerous consequences. It rarely occurs unless in- 

 duced by a purgative, and the excessive action of the medicine is prob- 

 ably to be explained upon the theory that the mucous membrane 

 sympathizes with the diseased laminae, is irritable, and readily be- 

 comes overexcited. The discharges are thin and watery, sometimes 

 offensively odorous, and occasionally persist in spite of treatment. It 

 may prove disastrous to the welfare of the patient by the rapid 

 exhaustion which it causes, preventing resolution of the laminitis, 

 and may even cause death. 



Sejjticemia and pyemia. — Septicemia and pyemia are unusual com- 

 plications and are seen only in the most severe cases, where bed sores 

 are present or suppuration of the laminae results. They die, as a rule, 

 within three days after showing signs of the complication. 



Pneumonia — the so-called metastatic — needs no special considera- 

 tion, for in its lesions and symptoms it does not differ from ordinary 

 pneumonia, although it may be overlooked entirely by the practi- 

 tioner. Examinations of the chest should be made every day, so as 

 to detect the disease at its onset and render proper aid. 



Sidehones. — A rapid development of sidebones is one of the compli- 

 cations, or, perhaps better, a sequel of laminitis not often met with in 

 practice. Here the inflammatory process extends to the lateral carti- 

 lages, with a strong tendency to calcification. The deposition of the 

 lime salts is sometimes most rapid, so that the " bones " are developed 

 in a few weeks ; in other instances they are deposited slowly and their 

 growth is not noted until long after the subsidence of the laminitis, 

 so that the exciting cause is not suspected. This change in the car- 



