DISEASES OP THE OX AND SHEEP. 217 



culosis may be protracted for months, and even a year may 

 elapse before the symptoms become marked. Indeed, cattle 

 which would not have been suspected to suffer from the disease 

 during life are often found after death to have tubercles in their 

 lungs and other organs. If a severe cold is taken by an animal 

 afflicted with this insidious disease, and sometimes from other 

 <5auseSj bovine tuberculosis may suddenly become acute. 



Occasionally the veterinary surgeon may be called to investi- 

 gate and treat an outbreak of more than ordinary virulence. He 

 may have, as Mr. J. B. Gresswell had recently, a valuable herd 

 ■of Alderneys under his care. In this particular instance the 

 malady took a form so severe that three animals died, while three 

 cows recovered under treatment, and two more were subsequently 

 affected dangerously. As is usual, the animals were extremely 

 weakened with the ravages of the disease, and they suffered 

 greatly from diarrhoea, the feces being of a creamy consistence. 

 This last symptom was found to be associated with, and explained 

 by, the presence of tubercular deposits in the bowels. The 

 lungs and intestines, indeed, were the organs which had been 

 especially attacked. 



For purposes of convenience, the symptoms of average cases 

 -of bovine tuberculosis may be spoken of as occurring in three 

 stages. 



First Stage.— Though, the ox, when attacked with the disease, 

 is less active and more sensitive to pressure, especially in the 

 regions of the withers, back, and loins, fattening and the 

 secretion of milk are not at first interfered with. The milk 

 is more watery, of a bluish tint, and while it contains less 

 quantities of nitrogenous matters, of fat, and of milk-sugar, 

 which are the nutritive elements, it is rich in alkaline salts and 

 other mineral constituents, particularly if the cows receive much 

 grain and bran or meal. The animal may give utterance to a 

 dry and deep but feeble cough. This will be noticed perhaps 

 when the ox passes either from a colder to a hotter atmosphere, 

 or from a hotter to a colder air, as in leaving or entering its stall, 

 A similar cough may follow exertion, or it may be brought on 

 by compression of the windpipe far more readily than in the case 

 of a healthy animal. 



At this early period of the disease there is seldom any 

 expectoration or nasal discharge. If the lungs are affected, as 



