RELIABLE POULTRY REMEDIES 



duced, roup may remain io a flock for many years. The first cold and 

 moist nights of the early fall and early winter cause all kinds of catarrhs, 

 which in many instances are followed by roup. Roup spreads rapidly in 

 the winter time and may attack from 10 to 90 per cent of the fowls in a 

 flock. Towards spring, the disease gradually disappears; during the sum- 

 mer month.s, a few birds remain chronically affected; and then the first cold 

 nights give the disease a fresh start. 



Young fowls and fowls of fine breeds are especially liable to roup. 

 While some poultrymen maintain that birds once having suffered from roup 

 never take the disease again, most of the experimental evidence tends to 

 show that no acquired immunity exists, as sometimes happens after other 

 diseases. Some fowls are, however, naturally immune, and never take 

 the disease. In the course of our. own experiments, a white chicken which 

 had never had roup, was inoculated with repeated and large doses of the 

 roup germ, but without effect. 



Roup is an Infectious Disease 



The first experiments were conducted, to find out whether or not Roup 

 was an infectious disease; and for this purpose, 10 healthy fowls which 

 had never been exposed to infection, were confined in a cage with diseased 

 birds; and after varying periods of time five of the healthy birds caught the 

 disease. Fourteen healthy birds were then treated by rubbing a portion 

 of the false membrane, or putrid nasal discharge from roupy birds upon 

 the normal or slightly scratched, mucous membrane of the nose or eyes; 

 and in this way, two birds were infected with typical roup. 



These experiments, therefore, show the infectious nature of the dis- 

 ease; but the degree of infectiousnens was not large. We must, however, 

 remember that when fowis are kept under natural conditions where they 

 are subjeci to cold, etc., the infectiousness may be much increased 



To sum up, roup or fowi diphtheria, canker, etc., is a complex of sup- 

 purative processes. The disease is genprally spread by sick fowls intro- 

 duced into healthy flocks. The germs are spread throughout a yard by 

 means ot the secretions, a though these do not always contain the casual 

 organism. The infected fowls are not very much different in their gen- 

 eral appearance and condition at the beginning of the disease, afid thus 

 they often take food and water for a long time, contaminating the food, 

 troughs and cups. As the germs cannot affect fowls so long as the mucous 

 membranes are intact and healthy, the disease does not spread for a cer- 

 tain length of time, although the germs may be present almost everywhere 

 in the yard. Then comes a change of weather, such as a 6old night or the 

 the beginning of fall or winter — and suddenly the infectiousness of the dis- 

 ease is increased and roup spreads rapidly among the birds. Unfavorable 

 weather, which causes colds and other affections of the mucous membranes 

 d^rectly, opens the way for infection. But it is possible that the roup bacilli, 

 having infected a number of fowls, may gain so much in virulence as to be 

 capable of entering into the tissues of the fowl without previous colds. Like 

 colds, other circumstances which weaken the cgnsfcitution of the fowls 



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