554 EXPERIMENTAL FARMS 



4 GEORGE V., A. 1914 



EXPERIMENTAL FARM, NAPPAN, N.S. 



REPORT OF THE SUPERINTENDENT— R. ROBERTSON. 

 DAIRY CATTLE GRADING EXPERIMENT. 



OBJECT OF EXPERIMENT. 



The object of this experiment is to discover the actual cash value of the pure- 

 bred dairy sire in a herd of common and mixed breeding in the increased production 

 of the progeny, as well as their proportionately greater market value. 



OUTLINE OF EXPERIMENT. 



Twelve heifers, born in 1909, were purchased in December, 1910, and bred at 

 once to the pure-bred Ayrshire bull purchased at the same time. These heifers were 

 of fair quality, but of common breeding, representing the average stock of this part 

 of Nova Scotia. 



Throughout the whole experiment the female progeny only shall be saved. 



The first crop of calves are naturally half-bred Ayrshire grades, termed First 

 Ayrshire Cross (A). All succeeding female progeny from these shall be bred to calve 

 at two years of age, and only the best of pure-bred Ayrshire bulls to be used thereon. 

 The first progeny from the First Ayrshire Cross (A) shall be termed ' Second Ayr- 

 shire Cross (A I) ' and their progeny in turn ' Third Ayrshire Cross (A II),' and 

 bo on till the end of experiment. 



A brief outline of the details of experiment would be as follows: — 



1. Prepare the ' Foundation Heifers ' and all succeeding female progeny for their 

 calving by being in good condition. 



2. Prepare for each succeeding calving by a four to eight weeks' rest and good 

 conditioning. 



4. Breed all ages for fall calving. 



5. Breed ' Foundation Heifers ' in the winter of 1910-11 to pure-bred Ayrshire 

 bull; 1911-12 to pure-bred Holstein bull; 1912-13 to pure-bred Guernsey bull; 1913-14 

 to pure-bred Ayrshire bull; 1914-15 to pure-bred Holstein bull; 1915-16 to pure-bred 

 Guernsey bull. 



6. Breed the progeny of each of the first cross heifers only to bulls of the same 



breed as their sires. 



7. The following diagram will give an idea as to nomenclature of the different 

 generations from each original cow. 



In this nomenclature please note: — 



1. Each ' Foundation Heifer ' will, in her heifers, originate a family. Hence her 

 number should be incorporated into the number of all her progeny. 



2. The year signifies the year of birth and, for ease in making diagram, is calcu- 

 lated as December of that year. 



3. The diagram shows the possible progeny of each heifer in the six successive 

 years of breeding, making no allowance for losses and figuring that all progeny are 



females. 



4. All the original ' Foundation Heifers ' should as much as possible be kept 

 until the fall of 1917, in order to have complete comparative data. 



