64 Feeds and Feeding. 



lent of more than 2 oz. of glucose must be burned for each lb. of 

 water vapor given off from the lungs and skin. Warming cold 

 water taken into the body does not necessarily mean that more food 

 must be burned, for animals evolve a large amount of heat in the 

 work of digesting food and converting the digested matter into 

 body products or work. (104) Due to this, many animals have an 

 excess of body heat. Comfortably-housed and well-fed steers and 

 dairy cows burn more food than is needed to keep their bodies 

 warm, and such excess may go to warm the water they drink, so 

 that no food is directly burned for that purpose. 



Armsby^ points out that in winter farm animals, watered but 

 once daily, then drink freely. The sudden demand for heat caused 

 by taking into the body this large quantity of cold water may ex- 

 ceed the available supply, with the result that some of the 'food 

 nutrients or body tissues are burned to meet it. Animals unduly 

 exposed to cold and those sparingly fed or with scant coats may be 

 directly helped by watering frequently or by warming their drink- 

 ing water. In cold regions in order to induce animals, especially 

 cows, to drink freely in winter, it is usually best to warm the water, 

 which should be comfortably accessible. 



When entirely oxidized in the body, 100 lbs. of starch or cellu- 

 lose will yield 55.5 lbs. of water and 163 lbs. of carbon dioxid, and 

 fats over twice as much water as starch. The nitrogenous com- 

 pounds yield a little less than the carbohydrates because they are 

 not entirely oxidized in the body. This shows that a very consid- 

 erable amount of water comes to the animal body from the dry 

 matter of the food they consume. It is probable that the water 

 which results from the breaking down of the food is used in the 

 anabolism, or building processes, of the body, rather than that 

 water which the animal drinks, tho this is not definitely known. 



88. Mineral matter. — The ash of feeding stuffs is of the greatest 

 importance to animals. This is shown by feeding them rations 

 freed as far as possible from mineral matter, in which case they 

 sooner or later die of mineral starvation. During mineral starva- 

 tion the nervous system first suffers in a perceptible manner; 

 marked weakness of the limbs, trembling of the muscles, convul- 

 sions, and great excitability result; and the animal generally dies 

 sooner than when no food is given.- 



^ Principles of Animal Nutrition, p. 439. 



* Kellner, Ernahr. landw. iNutztiere, 1907, p. 169. 



