METABOLISM AND FOOD 95 



still proceed regularly. Animals which are giving 

 milk are, however, exceptions to this, and they 

 ought to be given some salt to replace the chlorine 

 taken away in the milk. Milch cattle after being 

 two or three weeks without salt begin to show 

 great craving for it ; they gnaw the manger and the 

 walls, lick the hands and clothes of those attending 

 them, and even eat refuse and dung. No change 

 is to be noticed in their appearance or weight, nor 

 does the yield of milk decrease. This condition 

 can continue for some weeks or even for a year, 

 depending upon the animal and the quantity of 

 milk given, but finally the appetite decreases, the 

 eyes become dull, the coat " stares," and the 

 animal becomes very weak and thin. If salt is now 

 given recovery quickly begins, but if not, weakness 

 continues, and generally death follows, about time 

 of calving. These phenomena are due to the lack 

 of chlorine, not of sodium, for it has been found that 

 improvement and recovery follow if potassium 

 chloride is added to the food. 



Common salt finally possesses, in a very high 

 degree, the properties of a spice ; it improves the 

 appetite and makes many feeding-stuffs palatable 

 which, without salt, would not be readily eaten. It 

 further increases the flow of digestive juices (p. 40), 

 promotes activity of the circulation, and prevents 

 disturbances of the digestive apparatus, so a de- 

 ficiency in the food should not occur. 



