6 POULTRY DISEASES AND THEIR TREATMENT. 



as the same as that of the Chinese physician, who is primarily 

 employed to keep the patient from becoming ill, only secondarily 

 to cure him. 



Now there are fundamentally two factors involved in the con- 

 tinued maintenance of good health in poultry (or, for the matter 

 of that, in any other animal). These are: 



1. A sound and vigorous constitution, which if present, is. 

 something innate and "bred in the bone," and which, if absent, 

 must be bred into the stock. 



2. A system of poultry management (including feeding, hous- 

 ing, etc.) which is thoroughly and absolutely hygienic. 



Let us consider each of these factors separately in some 

 detail. 



Breeding for Health, Vigor, and Sound Constitution. 



To have a high degree of constitutional vigor in the founda- 

 tion stock is one of the most certain assurances that the poultry- 

 man will not be troubled with disease. This is of primary 

 importance. In order to breed constitutional vigor into the flock 

 the poultryman must train himself to recognize at a glance the 

 condition of his birds. Are they in good condition or not ? Re- 

 garding the aspect of fowls in health and disease Salmon has the 

 following to say : 



"We say that a bird is in good health when it appears lively, 

 has a clear eye, a bright red comb, is quick and active in its 

 movements, has a good appetite and when the various organs 

 perform their functions in the manner in which they are observed 

 to act in all birds that are vigorous and thriving. On the other 

 hand, we say a bird is diseased when some function or functions 

 of its body are not performed as they are the great majority of 

 individuals, or when some organ presents an unusual form or 

 appearance. Disease has, therefore, been defined as a life the 

 manifestations of which deviate more or less from the normal. 

 Practically, we say a bird is diseased when we observe that one 

 or more of its functions are not carried on in a normal manner, 

 or when we find unusual growths, injuries, or parasites affecting 

 any of its organs." 



In a recent article Dr. P. T. Woods (Amer. Poult. World, 

 Vol. I, Jan. 1910) gives some excellent advice in regard to 

 breeding for health and vigor. This is, in many respects, the 

 best brief summary of this important subject which we have 

 been able to find in the literature. He says : — 



