2 Diseases of Poultry 



have not affected others, marks them out as the weakest, 

 which unaided Nature would assuredly weed out, and which 

 if we preserve and breed from, perpetuate some amount of 

 that weakness in the progeny. Rheumatism, for instance, 

 can be cured ; of that there is no doubt. But the vast 

 majority who have had such success, agree that the effects 

 are either never recovered from, as regards strength and vigor, 

 or else that the original weakness continues ; and the same 

 may be said of some severe contagious diseases, such as 

 diphtheritic roup, which may affect the strongest. On 

 the other hand, many diseases also apparently contagious, 

 and so attacking healthy birds under certain predisposing 

 conditions of exposure or other coincident strain upon the 

 system, do not appear to leave serious results behind them, 

 and are tolerably definite in symptoms and character. It is 

 these which may be most successfully treated, and in which 

 treatment is most worth while where fowls of value are con- 

 cerned. But it is significant that nearly all breeders who 

 rear really large numbers of poultry, gradually come to the 

 conclusion that, except in special cases, with valuable birds, 

 the most economical treatment of serious disease occurring 

 in a yard is — execution. Concerning this matter each 

 must judge for himself." 



In the case of the utility poultryman, keeping poultry solely 

 for the eggs and meat they produce, practically the only 

 diseased conditions which it will pay him to treat at all are 

 those in which the treatment can be applied to the flock as a 

 whole, without the necessity of handling individual birds. 

 Thus, for example, in cases where the flock "goes off its 

 feed," or has simple indigestion or a mild cold, the birds 

 can be treated successfully as a flock. On the other hand, 

 in the case of the fancier, who has indi^'idual birds of con- 

 siderable value, there will be a much wider range of diseases 

 which he will feel that it is profitable for him to treat. There 



