BROODINESS IN DOMESTIC FOWL. 95 



The Material and its Treatment. 



The materials for the present study of the inheritance of broodiness are 

 the pullet-3''ear trap-nest records of the flock of Rhode Island Reds, bred 

 at this station from 1913 to 1917, primarily to furnish data on the in- 

 heritance of fecundity. The usefulness of these data is limited in one 

 important respect, since, as discussed in the section on variation, a j'ear's 

 record is not long enough to determine a hen's capacity for becoming 

 brood}'. Limitations in housing capacity and labor have hitherto pre- 

 vented the retention of non-broodies as long as was desirable. In the hand- 

 ling of the data, therefore, we have classified birds as brood}'- or non- 

 broody on the basis of the pullet-year records onlj^, even though on this 

 basis the non-broody class will contain more birds than it should. How- 

 ever, the theories of the inheritance of broodiness to which we have been 

 led could not be substantiated from the available data, even if the diffi- 

 culty under discussion were removed. 



Recognition and Treatment of Broody Birds. 



The recognition of a broody period is an easy matter with slight ex- 

 perience. The onset of broodiness is usually sudden. On the last visit 

 to the trap nests late in the afternoon one or more birds are found that 

 are very much disinclined to leave the nest. If they cluck and ruffle their 

 feathers the diagnosis is certain, and the birds are removed to the broody 

 coop to be "broken up." Sometunes part of the sjanptoms are lacking. 

 In case of doubt the bird is merely removed from the nest. By the follow- 

 ing afternoon, if she is reallj'' brood}^ all symptoms are ^^'ell manifest. 

 Mistakes are not easily made. 



The broody coop in which the broody hens are confined, in order to 

 prevent the instinct from running its normal course, is a box with slatted 

 sides, top and bottom. The routine practice in dealing with broodies is 

 to place all the broodies found in each pen in one of these coops. The 

 same coop also receives the broodies on each of the two daj^s following. 

 Three days later the entire lot is released as a unit. Thus, the birds are 

 confined from three to six days each, a period which is sufficient for the 

 majority to "recover from the attack." A few, however, require a longer 

 period of confinement. The confined broody individuals are supplied 

 ad lihitium with the same sort of food and water supplied the rest of the 

 flock. 



A bird must, as a rule, be classified either as broody or not broody, 

 though in a few rare instances birds have exhibited a part of the broody 

 symptoms onlj^, as, for example, wiien a hen clucks and ruffles her feathers, 

 but does not remain on the nest continuously, nor cease lajing. 



