VARIOLA VACCINAE. 209 



time. Unlike, however, the other contagious diseases of horned 

 cattle, and unlike variola ovinse, it is a disease which seldom or 

 never proves fatal in this country. In some instances, the con- 

 stitutional disturbance is rather severe, the mucous membranes 

 being particularly prone to participate ; the mouth becomes sore, 

 and there is drivelling of saliva. 



In hot climates the symptoms are succeeded by abdominal 

 pains, profuse diarrhoea, rapid wasting of flesh, and sometimes 

 death ; but in temperate climes the general symptoms are 

 slight diminution in the secretion of milk, with but little or no 

 loss of appetite. 



The contagium of variola vaccinae is an extremely small form 

 of micrococcus, usually called the Biiolococcus variolar d vaccince 

 (see Plate), in clear lymph, but in opaque, orange, and brown 

 lymph there may be three or even four forms of cocci, the 

 characteristic ones being in pairs or in quadruple arrangements, 

 which latter many think the typical form. From the small size 

 of the germs in vaccine and variolous lymph, Buist considers 

 that they are more to be considered spores of micrococci than 

 fully developed micrococci, and that this accounts for the less 

 intense local effects after vaccination with clear lymph. Among 

 the larger forms in opaque lymph are to be found what look 

 extremely like yeast cells {Torulce variolcv), these being con- 

 sidered possible derivates from the micrococci. Some observers 

 are of opinion that although the vaccine and variolous germs 

 may not be actually special forms of the yeast organism, that at 

 least both vaccination experiments with yeast and cultivation 

 investigations seem to point out a similar origin. 



When once the disease breaks out in a dairy, it is apt to 

 spread to the whole herd, unless precautions be taken against its 

 diffusion, by segregation of all affected animals and the employ- 

 ment of separate attendants, particular care being at all times 

 taken that the milker of an affected cow shall not touch a 

 healthy one. The milk should be drawn off with the teat 

 syphon, and, if the mammary gland becomes much inflamed, 

 fomentations may be necessary, with other treatment recom- 

 mended for " mammitis " (see Principles and Practice of 

 Veterinary Surgery) ; but in all ordinary cases of the disease 

 non-interference is to be strictly observed. 



p 



