Animal Diseases. 275 



After an incubation period of six days the temperature began 

 to rise, and the animal died on the i6th day. On making a post- 

 mortem examination I found the usual signs of Heart-water. 



No. 393 was used to inoculate No. 408, which died on the 14th 

 day. 



No. 408 w^as used to inoculate No. 411, which died on the 13th 

 day. 



No. 411 was used to inoculate No. 4"! 9, which died on the nth 

 day. 



This experiment, which has been carried out with every care as 

 regards the keeping of control animals in contact during the experi- 

 ment, and subsequently showing by inoculation that the controls 

 were still susceptible to virulent infection, admits me to say that 

 Horse-sickness can be transferred to goats, and that, when accli- 

 matised to the goat, it produces in this animal a virulent disease, 

 which is indistinguishable from the endemic disease of goats, which 

 is known in South Africa as Heart-water. 



HEART-WATER PRODUCED BY THE INOCULATION OF 

 THE BLOOD OF PROTECTION CAMP HORSES. 



I was enabled to get a protection camp horse sent into the 

 Institute, and w^hile there I bled it, and inoculated Goat No. 356 

 with 30 c.c. intravenously and 30 c.c. subcutaneously on the nth 

 Februar}'. 



On the 7th day the temperature rose, and remained high, 105F. 

 and slightly over, until the nth day, when it fell to loi, and the 

 animal then died. 



On making a post-mortem examination I found oedema at the 

 base of the heart of a semi-transparent character, extending up to the 

 aorta. The lungs were pale, but the left had a dark patch of con- 

 gestion about two inches in diameter, and being sharply circumscribed 

 within a group of lobules. The pericardium was quite filled with a 

 clear yellow serous fluid, which quickly coagulated when transferred 

 to a glass. The conditions found were thus absolutely typical of 

 what one obtains in ordinary Heart-water. 



I therefore conclude that the contagium which causes Horse- 

 sickness in the Equids of South Africa is responsible, under condi- 

 tions of relative virulence, for the infection of other species of the 

 domesticated animals. 



The means by which the virulence becomes relatively altered is 

 not entirely clear, but my colleague the Colonial Entomologist has 

 been able to produce Heart-water in goats and calves at Cape Town 

 by means of the progeny of Bont ticks taken in the Eastern Pro- 

 vince from infected goats. In this way, therefore, the very striking 

 observations of the late Mr. Webb has been proved to be correct. 



We are not, however, yet able to say that Heart-water is not 

 conveyed by any means other than the Bont tick. 



