POULTRY BREEDING 



Experimental Work of Genetists During Last Fifteen Years Has Shown Mode of 



Inheritance of Many Characters, but Has Not Materially Modified 



Practical Methods of Commercial Breeders ^ 



Rob R. Slocum 

 Scientific Assistant in Poultry Investigations, U. 



Washin<iton, D. C. 



S. Department of Agriculture, 



work are the short time necessary to 

 bring them to maturity, making it 

 possible to secure a new generation 

 each year, the relatively high fecundity, 

 making it possible to secure a large 

 number of offspring from a single 

 mating, and the readiness of the fowls 

 to breed at any season of the year. 



bateson's pioneer work 



Following the rediscovery of Mendel's 

 Law in 1900, there was begun and has 

 since been carried on a considerable 

 amount of experimental breeding of 

 poultry. The first work along this line 

 was that of William Bateson and 

 others as detailed in the reports to the 

 Evolution Committee of the Royal 

 vSociety of London. Since then many 

 others have taken up work of a similar 

 nature. In this country, the Carnegie 

 Institution's Department of Experi- 

 mental Evolution at Cold Spring Har- 

 bor, Long Island, N. Y., under the 

 direction of C. B. Davenport, has been 

 especially active along these lines. 

 Practically all of the breeding has 

 been cross-breeding with the object of 

 testing the behavior of characters of 

 the individuals crossed to see whether 

 they behaved in accordance with Men- 

 del's Law. Theory and results have on 

 the whole been in fairly close accord. 

 As a result of these experiments a 

 considerable mass of data has been 

 secured, most of which has to do with 

 the dominance or recessiveness of unit 

 characters of poultry and with the 

 limited inheritance of certain characters 



1 Address before the twelfth annual meeting of the American Genetic Association, at Berkeley, 

 Calif., Augusts, 1915. 



483 



IT IS not the intention in this paper to 

 enter into a detailed discussion of 

 the experimental work which has 

 been carried on in breeding poultry 

 in the last twenty-five years or to discuss 

 the methods used, but simply to sum- 

 marize briefly the results obtained and 

 to comment on the possible or probable 

 value of these results in practical poultry 

 breeding. While the behavior of the 

 characters of domestic poultry in inher- 

 itance, no matter what their nature, 

 is undoubtedly a study of great scientific 

 value and of general biological interest, 

 it is nevertheless true that only so far 

 as it has a bearing or a possible bearing 

 on the practical problems of poultry 

 breeding is it of interest to the great 

 mass of poultry keepers and others 

 vitally concerned with the vast poultry 

 industry. It is this latter phase 

 which is of paramount interest to the 

 writer. 



Domestic poultry as a subject for 

 experimental breeding has much to 

 commend it and has in consequence 

 been one of the most popular classes of 

 animals for this purpose. Not only 

 are chickens widely diversified as to 

 form and color, but in respect to many 

 other characteristics, such as comb, 

 number of toes, shank color, shank 

 feathering, etc., the difference is great 

 and the contrast sharp. Their com- 

 paratively small size with the resulting 

 feasibility of keeping a large number 

 at a relatively small cost is also a factor 

 greatly in their favor. But perhaps the 

 considerations which make chickens 

 especially desirable for this class of 



