68 FEEDING OF DOGS. 



tnie, that the want of food and the excess of it should both pro- 

 duce the same disease ; for it is very seldom that a dog is badly 

 fed for a considerable length of time, but that he contracts mange ; 

 and it is also as seldom that a dog is long permitted to eat to ex- 

 cess, without becoming mangy also. However, if the same clean- 

 liness and care were to be observed in both cases, the lean dog 

 would have the least of it, and his mange would also prove much 

 the most easy of cure^. 



^ To feed judiciously, the physiology of digestion should be understood. 

 All the juices of the body, and indeed all the solids likewise, are furnished 

 from the blood. These juices are in a continual state of waste, and the solids 

 are in a continual state of wear ; both of which (i. e. the waste and the wear) 

 take place in proportion to the exertion used. There must, therefore, exist 

 some means of recruiting this waste of the fluids, and some means of repairing 

 this wear of the solids. Nature has intended that these ends should be brought 

 about by food, consisting of solid and fluid substances; which, being masticated 

 and broken down into small masses by the teeth, and mixed with the saliva, are 

 rendered fit to be acted on when received into the stomach, where they meet 

 with a strong solvent agent, called gastric fluid ; by mixing with which they 

 become animalized, and, in fact, wholly altered. In a complete pultaceous 

 mass, called chyme, it is passed into the bowels, where there are little vessels 

 that strain and suck up such fluid parts as are fitted for nourishing the body, 

 and pass it forwards in very minute streams into glands, called mesenteric. 

 These glands empty their contents, then called chyle, into one common 

 receptacle, from whence the chylous fluid is poured into the heart to form blood. 

 The blood therefore is constantly recnxited from this source ; and from this 

 description it will naturally suggest itself, that when food is withheld, the blood 

 must waste ; and when this is the case, the fluids of the body must naturally 

 decrease, and the solids must wear fast. On the contrary, when food is taken 

 in too great quantities, the blood will, in that case, become too rich, and be 

 generated in too large quantities ; and, as the solids are limited in their growth, 

 so some, or all, the fluids of the body will be formed from the superabundant 

 blood in too large proportions. The moisture that goes to the skin will pro- 

 bably become acrid, and form a disease called mange : the sebaceous glands of 

 the ear, instead of forming wax, will pour out blood or matter, then called 

 canker ; or the unnecessary quantity will flow to the teats, where, if it is not 

 the time of pregnancy, it will form a spurious secretion and induration. When 

 these evils do not immediately siiccced, the superabundant blood expends 

 itself in secreting an inordinate quantity of the oily fluid called fat, the effects 

 of which are detailed under Excessive Fatness. 



