CHAPTER XVIII 



The Inheritance of Milk and Butter-fat Percentage 



in Crosses of Animals Differing Widely in the 



Amounts of These Variables 



Each student may review critically one of the following references 

 and report on it. After the reports, have a general discussion of 

 the subject by the members of the class with the object of coordi- 

 nating the work of the different investigations and deriving 

 conclusion of general application. The object of the reviews should 

 be foremost in mind, namely, how the particular work furnishes 

 evidence on the problem of the inheritance of milk yield and butter- 

 fat percentage and the effects of dominance, heterosis, etc. 



REFERENCES 



Castle, W. E. 1919. Inheritance of quantity and quality of milk production in 



dairy cattle, Proc. National Academy of Sciences, vol. 5, pp. 428-434. 

 Lawritson, M. N., et al. 1919. Purebred sires effect herd improvement, Cir. 



8, Nebraska Agric. Exper. Station, pp. 1-15. 

 Olson, T. M., and Biggar, G. C. 1922. Influence of purebred dairy sires, 



South Dakota Agric. Exper. Station Bui. 198, pp. 434-467. 

 Kildee, H. H., and McCandlish, A. C. 1916. Influence of environment and 



breeding in increasing dairy production, Iowa Agric. Exper. Station 



Bui. 165, pp. 383-402. 

 McCandlish, A. C, and Winters, L. M. 1920. A study of bulls, Jour. Dairy 



Science, vol. 3, pp. 529-539. 

 McCandlish, A. C. 1920. Environment and breeding as factors influencing 



milk production, Jour. Heredity, vol. XI, pp. 204-215. 

 McCandlish, A. C, et al. 1919. Influence of environment and breeding in 



increasing dairy production — II, Iowa Agric. Exper. Station Bui. l sS . 



pp. 65-88. 

 Van Norman, H. E. 1907. Influence of pure bred sires, Report of Penn. State 



College, pp. 129-145. 

 Beam, A. L. 1915. A study of the dairy herd records of Pennsylvania Experi- 

 ment Station, Report Penn. State College, pp. 349-386. 

 Wilson, J. H. 1917. The effect of the sire on the herd, Vermont Agric. Exper. 



Station Bui. 202, pp. 39-44. 



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