Oct. 7, 1918 Crosses between Dairy and Beef Breeds of Cattle 5 



CROSSBRED HERD 



Time of beginning matings 

 The crosses herein described are the result of matings since the spring 

 of 191 3. For the number of animals there were to work with this is 

 satisfactory progress, and it is expected that with reasonable success the 

 first-generation crosses will soon be complete. 



plan of matings 



The plan calls for reciprocal matings of all of the important dairy and 

 beef characters. At first there were some crosses made which were later 

 found to be hampered by the fact that it was impossible to keep the bulls 

 necessary for the Fj generation. Consequently only the heifers were 

 saved for future breeding purposes. The breeds chosen for the foundation 

 of the Fi Mendelian herd were Jersey, Holstein-Friesian, and Aberdeen- 

 Angus. The ultimate choice of these rests on the fact that these breeds 

 have all the outstanding characters which were desired for analyses, 

 such as low and high milk production, lOw and high percentage of fat, 

 poor and good beef qualities. Besides these, the minor characters of 

 color, secretions, and conformation offer considerable range of variability 

 for analyses in conjunction with the analyses of the economic characters. 

 In handling the Mendelian herd and its parential generation, it is the 

 plan to have them under as nearly the same conditions as the rest of the 

 herd animals as it is possible. They are raised side by side with the 

 other herd animals and treated in exactly the same way, by the same 

 herdsman. In the breeding of the animals a rack is used wherever there 

 is a marked difference in size or where it is desirable to facilitate the 

 matings. After the mating has taken place, the herdsman fills out one 

 of the service record blanks shown in figure i . 



If the first service fails, another service is given at the next period of 

 heat. Each of these service blanks are filled out and carefully filed. When 

 a birth takes place, the herdsman files another blank recording such birth. 

 The corresponding service and birth blanks are then filed together. Each 

 animal is tagged at birth with a number corresponding with that on its 

 birth blank. These tags are the common metal tags put through the carti- 

 lage of the ear. Besides this, when the animals are old enough, they are 

 branded on the shoulder with their distinguishing number. Any chance 

 in mistake of pedigree of these animals is thus reduced to a minimum. 



All of the animals are kept until they are 200 days old, when they are 

 measured for the study of conformation in relation to milk production. 

 Besides this description the animals are carefully examined and a descrip- 

 tion of the color and other outstanding features made. Photographs of 

 all of the animals are taken before they are sold and kept in the perma- 

 nent files of the Biological Laboratory for reference. 



description of matings 

 Before passing to the analyses of the individual Fj hybrids it is well to 

 have clearly what each individual mating was and what differences 

 between them could be expected. To this end Table V has been drawn 

 up to show the matings which produced each crossbred. 



