Dropsy of the Amnion and Allantois 427 



cows, a large percentage of the animals afEected with this malady 

 in a given year, when the food had been somewhat damaged, and 

 consequently afforded insufficient nourishment. 



A very interesting fact in connection with hydrops of the 

 amnion and allantois was observed by us among a herd of Short- 

 horn cows, with which an American buffalo or bison was allowed 

 to consort, and a number of which became impregnated by him. 

 Almost without exception, during one year, all the cows which 

 were in calf by the buffalo perished from hydrops amnii, while 

 the other cows upon the farm, of which there were 100 or more, 

 did not suffer from the malady. Similar observations have been 

 recorded by others. 



The cadaver of an animal which has died from this disease is 

 emaciated and anemic. In some cases the abdominal muscles 

 may have become ruptured, because of the great weight which 

 they have been called upon to bear, in addition to the weak- 

 ened state of the muscles as a result of the dropsy. The uterus 

 is greatly distended, pale and thin-walled. Kammermann 

 has recorded a rupture of this organ, Garreau found the 

 membranes destroyed. Harms observed them ruptured, and 

 Schutt found plastic clots floating in the fluid. Harms records 

 that the fetuses are, as a rule, feebly developed and may also be 

 dropsical. The liver and kidneys show appearances of paren- 

 chymatous infiltration, The post-mortem appearances have not 

 been well studied. Though most of the animals die, they have 

 generally been handled before death, the fetal membranes torn 

 and the liquid contents expelled or removed, so that the evidences 

 of the actual conditions present during life have been largely 

 obliterated prior to the death of the animal. 



The course of the disease is variable. Most animals live until 

 near the date for the normal close of pregnancy, but they do not 

 as a rule give birth to young without aid. In the cow, a large 

 proportion of the animals go down and are unable to stand be- 

 fore the veterinarian is called and may perish before the time 

 for parturition arrives. When gestation continues for the 

 normal time, there is an absence of power on the part of the 

 mother to bring about the expulsion of the uterine contents. 

 The long continued, great distension of the uterus has destroyed 

 the contractile powers of its walls. The abdominal walls also 



