4 VETERINARY LECTURES 



(n) Skin. — Hair Follicles, Sweat Glands, etc.; Affections; 



Diseases. 

 (12) Urinary and Generative Organs.— Parturition and 



Diseases. 



11. Nutrition is the process by which all organic structures, 

 whether vegetable or animal, are developed, replenished, and repro- 

 duced — i.e., nutritive development, nutritive repletion, and nutritive 

 reproduction. When all the various structures are in a normal 

 condition, the body may be said to be in a state of health, to 

 maintain which certain materials are necessary so as to replace the 

 changes of matter (more or less accelerated) that are ever going on, 

 as there is not a thought or a movement of the body without some 

 expenditure of tissue. This tissue must be, and is, renewed by the 

 process of nutrition, which is upheld and carried on by means of the 

 food taken into the stomach, which, when digested and subjected to 

 the secretions of the various glands connected with the digestive 

 organs, is transformed into suitable material, which may be either 

 stored for future use, or pass directly into the blood in combination 

 with lymph from the absorbent vessels, and by means of the circula- 

 tion the new materials are brought in direct contact with the minute 

 cells of the various tissues of the body. Each cell with its atomic 

 activity and selective power extracts its own suitable pabulum for its 

 own special function, while it passes the waste product (debris) into 

 the blood-stream to be eliminated from the body by the excretory 

 organs (see Digestive Organs). In the animal kingdom, before 

 healthy nutrition can be successfully maintained, certain conditions 

 are required, viz. : 



(1) The part to be nourished must be in proper state of 



health. 



(2) The blood must be pure, and not too far distant. (There 



are some structures into which the blood does not go, 

 it only flows near ; for instance, the cartilage covering 

 the ends of bones in the formation of joints. In such 

 cases nutrition is carried on by ' imbibition,' or sucking 

 up.) 



