CHAPTER XV 



SUCCULENT AND WATERY FOODS 



General Characteristics. The distinction between dry and 

 watery foods is at once plain and important. The former 

 contain only hygroscopic moisture, which rarely exceeds 20 

 per cent, of the whole, and in many cases it is less than 

 half that amount. The average is, perhaps, from 10 to 12 

 per cent. The latter, the watery foods, consist of fresh vege- 

 tables which usually contain over 75 per cent., and not in- 

 frequently as much as 90 per cent, of water. The percentage 

 of nutrients in such watery foods is, therefore, relatively 

 small, and large quantities of the foods are required for 

 nutrition of animals. 



Thus, apart from any differences in composition or digesti- 

 bility due to drying, i Ib. of hay would be equal to about 

 4.5 Ibs. of the fresh grass from which it was made. An 

 animal which required 20 Ibs. of such hay for maintenance 

 would need from 80 to 90 Ibs. of grass for the same purpose, 

 and it would need an additional 50 Ibs. or so in addition for 

 milk production or fattening. This total quantity of grass 

 if the animals were able to consume so much would 

 contain nearly n gallons of water. This is more than they 

 require or would consume if fed on dry food under ordinary 

 conditions. 



The excess of water is, of course, rapidly excreted : but 

 as it is first raised to the temperature of the animal's body, 

 there is a certain loss of energy (p. 124). There is some 

 reason to believe that the increased volume of urine carries 

 with it a larger amount of nitrogen, but this has not been 

 definitely proved. It has also been suggested that large 



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