65 



New Hampshire Station, Bulletin No. 9, February, 1890 (pp. 16). 



Ef^M':ct of food upon the cjualitv of milk, G. If. Whitciier, 

 B. S. — This is a popular article, including only brief outlines of experi- 

 ments made at the station. The nature and composition of niiliv are 

 ('Xi)l:iined and partial results given of analyses at the station of the 

 milk of four cows of each of four breeds — Jersey, Ayrshire, Holstein and 

 iShoi'thorn. 



It is urged tliat the quality and composition of the milk are affected 

 by: (1) Breed; (2) individual characteristics; (3) period of lactation, 

 i. e. the time since calving ; (4) time of milking, morning vs. night ; 

 {~}) frequency of milking; (0) portion of milking, i. c. the first drawn 

 vs. strippings. It may fairly be claimed that alio/ these are independent 

 of the food. 



Breed and individual characteristics. —The fat of the Jersey milk 

 ranged from 4.34 to COG per cent, average 5.12 per cent; of Ayrshire, 

 from 3.81 to 4,55, average 4.28 ; Holstein, from 2.84 to 3.54, average 3.13 ; 

 Shorthorn, from 3.50 to 4.15, average 3.8G. The cows had been fed 

 practically alike. Analyses are cited in support of the statement that 

 "the average differences in the fat percentage of their milk are due to 

 the breed, not to the feed." That one of the Jerseys would make a 

 pound of butter from 15 pounds of milk while another would yield only 

 a pound of butter for 21 i)ounds of milk, and this on the same kind of 

 food, is one of numerous illustrations cited of what is urged as a general 

 principle, that "breed and individual characteristics are the two great 

 factors that determine the richness of milk." 



Period of lactation. — As illustrations of the influence of the period 

 of lactation on the quality of the milk, it is stated that the milk of one 

 cow contained 3.5 per cent of fat in November and December, 1888, 

 and 3.0 per cent in May, 1889, on the same food; and on pasture feed 

 4.1C ])er cent in August and 4.23 per cent in September; while the 

 milk of another cow averaged 3.6 percent in November and December, 

 1888, 3.0 per cent in April, 1889, and 4.4 per cent in May. 



Mornimfs vs. nights milk. — In the case of three cows whose milk was 

 analyzed night and morning daily for a full j'ear, "the morninffs milk 

 was richer than the nighfs milk during the time that the cows were on 

 l^asture feed, but when the same cows were put into the barn the re- 

 verse was true; that is, the night's milk was the richer." 



Tlie ilifil'eniure between moruing and night's milk is quite marked ; thus, during: 



.Tune, July, and August a .Jersej^ cow gave milk which averaged as follows : 



Morning's milk, G.26 per cent. ? . ./. m .- < 



Night's milk, 5.7,5 fer cent. \ Average, 6.01 per cent. 



Did'erence, Q.^A per cent in favor of morning's milk. 



The same cow during .January, February, and March gave: 



Morning's milk, 5.81 per cent, ^ » ^ n^ ,. ' 



Night's milk, 6.:?0 per cent, ] Average, 6.0o per cent. 



Difference, 0,49 per cent in favor of night's milk . 



Other C0W8 gave like results, not ao marked. 



