JOmAL OF AGRIOITIAI ISEARCH 



Vol. XV Washington, D. C, October 7, 1918 No. i 



STUDIES IN INHERITANCE OF CERTAIN CHARACTERS 

 OF CROSSES BETWEEN DAIRY AND BEEF BREEDS 

 OF CATTLE ' 



By John W. Gowen 

 Assistant Biologist, Biological Laboratory, Maine Agricultural Experiment Station 



INTRODUCTION 



An outstanding need of present-day genetics is the analysis of the 

 hereditary variations in the economically important domestic animals. 

 It is the purpose of this paper to present a preliminary analysis of the 

 data from the first-generation crosses of the prominent dairy breeds of 

 cattle on the beef breed Aberdeen- Angus (22, 42)} 



This work has been undertaken as a link in the chain of evidence 

 necessary to the final solution of the problems which are connected 

 with the inheritance of milk and butter-fat production. Consider- 

 able work has already been done in this laboratory in the analysis of 

 the variation in these characters without immediate regard to the inherit- 

 ance of such variation {2J-S8). These studies, it is believed, lay the 

 foundation for the accurate analysis of such characters, for without a 

 comprehensive understanding of the normal fluctuation of such quan- 

 titative character as milk production, it is practically impossible to 

 determine such inheritance. 



Further, the only method now known by which an adequate analysis 

 of these laws of hereditary can be made is by hybridization experiments 

 so carefully planned that the segregating factors may be analyzed sepa- 

 rately. To that end a crossbred herd is being formed to accumulate as 

 much material as possible for the analysis of such hereditary variation. 

 This crossbred herd has now gone into its second generation. It seems 

 wise, therefore, to make a preliminary analysis of the data of the first- 

 generation herd. 



This paper will have as its object the analysis of the inheritance of the 

 more prominent characters of the first generation of this crossbred herd. 



The plan of the work and its early prosecution was carried on by 

 Dr. Raymond Pearl. Through the exigencies of the war the analyses 

 of the data so far collected and the further prosecution of the work has 

 fallen to the author. The results of this analysis are presented in the 



1 Reference is made by number (italic) to "Literature cited," p. S4-S7- 



2 Papers from the Biological Laboratory of the Maine Agricultural Experiment Station, No. 120. 



Journal of Agricultural Research, Vol. XV, No. i 



Washington, D. C. (l) Oct. 7, 1918 



po Key No. Me.-ia 



