418 Veterinary Medicine. 



The impure stable air lowers the vital tone of the animal, 

 especially if the impurity has come from animal exhalations. 



The same is true of clamp air, " a damp ship is an unhealthy 

 one," and Bowditch and Buchanan pointed out the especial preva- 

 lence of tubercle in cold, damp, undraiued, foggy localities. 

 This does not hold for all damp lands, yet damp, fog, and cold 

 are especially hurtful in presence of the germ. 



INSUFFICIENT OR UNWHOLESOME FOOD. 



Starvation and indigestible or innutritious food contribute to 

 debility, and lessen the power of resistance. Hence in the poor, 

 half starved denizens of city slums, and among neglected herds 

 of cattle, tuberculosis, once introduced, makes rapid and exten- 

 sive ravages. Conversely overfeeding often acts in the same 

 way, developing indigestion and thereby robbing the tissues of 

 their proper nourishment, 



HEAVY MILKING. 



In dairy cows, of milking breeds, the drain on the system is 

 liable to prove too great, under a ration-for-milk, warm sloppy 

 mashes of grains, bran, middlings, roots, distillery swill, exclusive 

 diet of silage, saccharine roots, or marc, warm drinking water, a 

 warm atmosphere, liberal salting, and enforced idleness in the 

 stall, with careful stripping of the bag. The butter cows, 

 (Jerseys, Guernseys, Alderneys, etc.) are especially liable to 

 suffer, as the greater the yield the more the system is robbed of 

 the adipose material which is so needful to a vigorous health. 

 When the cow has been reduced to a high-pressure milk factory 

 her physical size reduced to obviate the need of a large sustaining 

 ration, and her milking capacity stimulated to the highest degree, 

 the presence of the tubercle bacillus is especially dangerous. 



CONFORMATION. 



It was formerly held that cows with heads narrow between the 

 horns, small thin necks, narrow chests defective also in depth and 

 length, loose projecting shoulders and elbows, pendent, pot bellies, 

 with hollow flanks, and a general laxity of the frame were 



