Influence of the Breed. 53 



varies between 3.5 to 3.6%, while the English Shorthorns and 

 Ayrshires give 3.7 and 3.8% ; the richest in fat is the milk of the 

 Vogelsberger and Harz cattle (3.9 to 4.2%) and that of the Jer- 

 sey with 5 to 5.4% (Ramm). Reference should be made here to 

 the following results of tests of production made with Simmenthal, 

 Vogelsberger, Westerwaldern and Lahn breeds of cows. 



Simmenthal Lahn Vogelsberg Westerwald 

 Average weight of the 



tested animals 578* 502 427 395 kg 



Average production 2495 2650 1919 1878 



Fat contents 4.001% 4.001% 3.74% 4.1% 



Individual maximum production .... 4562 3955 3800 3234 kg 



For 100 kg. body weight 431.1 528 450 477.4 " 



*The cow with maximal production stood last year in ninth place. 17 cows pro- 

 duced over 3000 kg. each. 



The fluctuation is not in fat content alone, but also in the 

 other solid substances. Milk which is rich in fat as a rule contains 

 more of the other solid constituents as well. The proportion of 

 individual factors of the dry substances is variable ; in cattle from 

 the highlands for instance, the casein was 76.24% of the dry sub- 

 stance, in cattle of the lowlands it averaged 73.78% (Fischer). 



Fat from the milk of the mountain breeds is generally under otherwise similar con- 

 ditions, the richest in fatty acid of molecular weight; the fat globules of the breeds of the 

 lowlands are smaller than the fat globules of the cattle from the highlands. Babcock 

 mentions that Jersey and Guernsey cows produce larger and more uniform fat globules 

 than the Holsteins, while Ayrshires have small, irregular fat globules in their milk. Milk 

 with large fat globules is preferable for butter making, since these produce butter of 

 good consistence and good taste with a low melting point. 



The ash content of milk from highly bred animals is some- 

 times somewhat lower in CaO and P 2 5 than that of the common 

 breeds, but the fluctuation is such that definite deductions cannot 

 be established. In highly improved breeds Pages found: CaO in 

 0.143 to 0.227% and P 2 6 5 in 0.18 to 0.273%; in common breeds 

 the same elements amount to 0.15 to 0.204, and 0.153 to 0.296, 

 respectively. 



These characteristics of breeds are general, but they are not 

 so constant that individual strains, individual families, and espe- 

 cially particular animals may not present exceptions. This fact 

 forms the basis of breeding for increased milk production within 

 individual breeds. 



Good milk cows should be bred to bulls, whose mothers and sisters were or are 

 known to be good milkers, and then it may be expected that the good characteristics 

 of the family will be inherited. In experiments extending over eight years Hogstrom 

 tried to discover whether the characteristics of producing milk of certain fat contents 

 could be transmitted by bulls to future generations. The large majority of female 

 progeny produced a higher fat content than the milk of their mothers, which points 

 to a positive influence from the male animal. In cases in which the fat content of the 

 mother was 3.08 to 3.77% the fat content of the milk of the daughter increased mate- 

 rially;- but as soon as the fat reached or exceeded 3.77%, the influence of the bull was 

 no longer sufficient to further increase the percentage of fat, and the percentage re- 

 mained lower than in the mother. (The experiences of Hogstrom 's were confirmed by 

 the rule laid down by Galton.) 



