218 ANNUAL REPORT OF THE Off. Doc. 



to rise. There are, however, many exceptions to this rule. No at- 

 tempt has been made to test this matter in long periods but only as 

 to daily or weekly fluctuations. 



SURROUNDINGS. 



The e^A'ironmental differences, the nervous excitement of the cow 

 already mentioned, as they vary from time to time, may cause fluc- 

 tuations in the quality of the cow's milk. The change from barn to 

 pasture, or the reverse, lack of water, poor water, drying pastures, 

 new milkers and the like, may and often do have influence. Then, 

 too, it must be confessed that there sometimes occur fluctuations in 

 the quality of the milk of a cow, and, occasionally, of a herd for a 

 week or more, for which no rational explanation can be offered, 

 changes which, because of care in sampling and testing and the con- 

 ditions surrounding the operations, are removed beyond all likeli- 

 hood of being due to error rather than to fact. There is much that 

 we do not know about cow nature and cow doings in milk-making. 

 And here, as ever, those who know- the most are those who impute 

 the least, while those less well informed are the more suspicious of 

 wrong doing. 



An editorial in a recent number of Hoard's Dairyman is very much 

 to the point in this connection. It says: 



''The cow is not a machine that will turn out the same quantity or 

 quality of milk from day to day, and consequently the milk varie> 

 according to the physical and, perhaps, mental condition of the 

 animal. The physical comfort or discomfort of the animal is re- 

 flected in the milk pail, and if the great mass of dairymen would 

 only recognize this fact, it would have a beneficial effect on the state 

 of the pocket book. 



In a careful record of the yield of a herd of cows for several years 

 the following facts were noted: 



They varied in quality of milk from one milking to the next, and 

 from day to day, the quality rising and falling without apparent 

 cause. The changes were usually wathin 1 per cent, of fat, but one 

 cow changed 2.G8 per cent, in two days. 



The average change during the period of lactation was 1.34 per 

 cent, and the greatest change 2.78 per cent. 



The above herd was exceptionally well taken care of and sheltered, 

 and the changes in quality of milk were thus much less than would 

 be noticed in cases of animals kept under less comfortable conditions. 



The dairymen should r-emember that exposure to cold, drinking 

 large quantities of cold water, exposure to cold rain, fright, worry, 

 heat, flies, and dogs, walking several miles over poor pasture for food, 

 starvation, soothing the cow with kicks or milking stool, will all re- 

 move fat from the milk and make such treatment more expensive 

 than good shelter and kind treatment. 



