20 THE GAME BREEDER 



THE BLACKHEAD DISEASE. 



Contribution from the Agricultural Experiment Station 



Rhode Island State College. 



With each year of experimental work only by carefully devised feeding ex- 

 on the blackhead disease conducted at periments accompanied by microscopical 

 the Rhode Island Agricultural Experi- examinations of the eliminated products 

 ment Station, it has become increasingly of living birds, and of the intestinal and 

 evident that this destructive malady of cecal content of those that die. 

 turkeys is not an infectious or commu- But while this work is in progress, 

 nicable disease, but a disease of captivity, there are certain general phases of the 

 a disease of management. With this subject of management which may ad- 

 recognition, the question of prevention vantageously be considered with relation 

 becomes more largely an ecological prob- to their bearing upon the raising of 

 lem to be solved by biological methods, turkeys. 



This does not necessarily mean that the At the time of the preparation of the 

 question has become easier of solution, former Extension Bulletin* it was not 

 but it does mean that the experimental impossible, at least on the basis of any 

 attack can now be made upon definite experimental work then conducted, to 

 and probably vulnerable points in the make recommendations regarding the 

 disease chains, whereas in the past, the feeding and management of turkeys on 

 efiforts have necessarily been more at free range. Since the publication of the 

 random and, taken as a whole, not foe- earlier bulletin, however, further results 

 ussed upon what now is considered the have been obtained from a study and 

 most important phase of the problem observation of methods that are espe- 

 of prophylaxis. Thus, though not yet cially adapted to range conditions in con- 

 solved, the problem has been consider- trast to methods employed in yards and 

 ably narrowed in its scope ; and as a re- pens. Although definite conclusions may 

 suit more intensive study upon the fun- not be drawn on the basis of so short 

 damental features is made possible. a study of this phase of the blackhead 



Looking at the matter in this light, problem, the greater popular interest 

 the problem of the feeding and manage- which attaches to this method of rear- 

 ment of turkeys with reference to the ing, together with the large number of 

 prevention of blackhead becomes the inquiries received at the R. I. State Col- 

 most important phase of the study. It lege regarding field management as op- 

 becomes an attempt, not to prevent the posed to pen management, make it ad- 

 entrance of the blackhead parasites, for visable to present at this time a brief 

 this is now known to be impossible; not consideration of several points of man- 

 the killing of the parasites after they agement, including nesting, incubation of 

 have entered the intestinal tract, for this, the eggs and the brooding and feeding 

 in the light of our present knowledge, of the young poults raised on range. It 

 is probably impracticable; it is the at- should not be construed from the fol- 

 tempt to control the development of the lowing paragraphs that the blackhead 

 parasites in the intestinal canal, and by problem is yet solved or that the plan 

 suitable feeding methods to prevent the of rearing now presented is the best plan 

 invasion of the tissues. What must now that can be devised. In connection with 

 be learned is how various food sub- the nesting and brooding alone, there, 

 stances, both qualitatively and quanti- are probably several good methods which 

 tatively considered, affect the develop- would be successful enough in them- 

 ment of the blackhead parasites in the selves if the blackhead disease could be 

 young turkey. This can be ascertained prevented. It has now become clear that 



