278 Maine Agricultural Experiment Station. 1919. 



for milk production which may lead to low milk production in 

 her daughters. This possibility will be considered further. 



Figure 28 shows the milk production of Crossbred No. 2 

 on a monthly basis. The significance of the three different lines 

 is the same as that for figure 27. Crossbred No. 2 record is 

 unfortunately based on only one lactation record. The record 

 for Canada's Creusa is based on five lactation records. The 

 record for the sire is that of the Holstein-Friesian milk pro- 

 duction for this herd at 2 years as previously described. The 

 curve for the milk production of Crossbred No. 2 clearly fol- 

 lows that of the Holstein-Friesian, or the high milk producing 

 breed. The continuation of the lactation from the eight months 

 on for Crossbred No. 2 would clearly follow that of the Hol- 

 stein-Friesian parent. Unfortunately this record is not available 

 as the cow on the tuberculosis test showed a temperature, was 

 judged tubercular and killed. Her autopsy did not however 

 show any lesions which were noticeable. Her record is, there- 

 fore, insofar as it goes representative. 



The milk production of Crossbred No. 11 is clearly inter- 

 mediate between that of her dam Delva Johanna DeKol 146774 

 and her sire Lakeland's Poet 102603 for the first three months 

 of lactation. From the time on this cow follows closely the 

 milk production of the high milking parent Delva Johanna De- 

 Kol. The records of the crossbred cow and her pure bred dam 

 are probably not quite representative. The crossbred record 

 consisted of the average of two corrected records, that of the 

 Holstein-Friesian dam consisted of the average of seven cor- 

 rected records. Inasmuch as the crossbred cow, No. 11, had 

 a much better corrected two year old record from the three year 

 old lactation than she did from her two year old lactation, it 

 probably means that her milk yield as shown in figure 30 is not 

 quite representative of her capacities. This might well be so 

 because she started her first lactation before her growth was 

 anywhere near completed. In any case the answer to this hy- 

 pothesis will come in future lactation records. As it stands at 

 present, therefore, the only conclusion that can be drawn is 

 that the milk production of the crossbred is lower than that of 

 her dams for the first four months of lactation. From this point 

 the milk production is approximately the same, that is, follows 

 closely or equals the milk yield of her high producing parent. 



