576 EXPERIMENT STATTON RECORD. 



iiiforiuntion i>n ninrUct iiii; ('.i,',i,'s. oIiImIiuhI in part from and in answer to in- 

 (inirii'S sent to v^^'^ Imycrs. Snii.Licsdons are jiiven for preventing losses that 

 now occur because many l)a(l ej;j,'s are sent to marlvet. 



Judging and valuation of ostrich feathers and feathers required by the 

 trade for special purposes, R. W. Thornton (.If//-. Join: Cape (huxl llnitr. ,'?,7 

 (J'JU!)). .\o. a, t>l). (iSO-dSC. figs. 7). — A discnssion of llic types of I'catliers in 

 greatest murliet demand. 



DAIRY FARMING— DAIRYING. 



The efficiency, economy, and physiological effect of machine milking, V. W. 

 Woix and (J. C. Humphuky (Wiscdii.siii Sta. h'cscdrctt liiil. .'>. i)tt. (U-l'if^. /i(/s. 

 9). — The exi)enments reported in this Imlletin covered a i>eriod of 2(i months 

 and involved 2!) different cows. 



In 40 trials during a period of 2(! weeks there was a wide variation in the 

 rate of decrease in the weekly production of milk when a change was made 

 from hand milking to machine milking, but on the average the decrease was 

 no greater than that fi-om a change in hand milkers. Comparisons were ob- 

 tained for 10 days with cows on machine milking and for corresponding periods 

 on hand milking the same cows for from 1 to 4 years for the various cows. 

 The average weekly production for the cows during the machine milking was 

 1.52.1 lbs. of nulk and 7.11 lbs. of butter fat, and during the corresponding 

 l»revious lactation periods on hand milking 1G2.7 lbs. of milk and 7..5.S lbs. of 

 butter fat. 



Unfavorable results obtained with the machine at one time were thought to 

 be due to the use of a too high vacuum. " In order to avoid any injurious 

 influence on the milk-secreting power of the cows, it is evidently of vital im- 

 portance not to maintain a higher vacuum than l(i in. at a maximum, and, in 

 case of a mixed herd, to maintain as uiiiform a vacuum of IT)* in. as possible." 

 More or less trouble was caused by abnormally small or large teats or when 

 the teats were vei'y close together. A fleshy or ill-shaped udder also interfered 

 with the efficiency of the machine. 



As regards thoroughness of the milking, the conclusion reached was that 

 after the cows had become accustomed to the machine it is practically equal to 

 that of good hand milking and is doubtless superior to that done on many dairy 

 or other farms. The amount of fat in the strippings did not tend to increase 

 in machine-milked cows when kept in the stable. The results were also satis- 

 factory for pasture conditions in the case of most cows. Although definite con- 

 clusions were not reached, it was thought that possibly machine milking not 

 followed by stripping will have an injurious effect on the cows which do not 

 give down their milk readily. It is pointed out that from a financial point of 

 view it will probably not pay to install a milking machine except in the case 

 of large herds or where a farmer with a small herd wishes to be independent 

 of hired help. 



An investigation of the bacterial content of machine-drawn antl hand-drawn 

 milk was made by E. G. Hastings and C. Hoffmann. Bacterial counts showexl 

 that in the case of samples from the individual animals the results are slightly 

 in favor of the machine; with the composite samples the reverse is true. No 

 difference in the content of acid-forming, liquefying, and inert bacteria was 

 noted. A series of determinations of the number of leucocytes present in the 

 milk of a number of animals was made before and after the introduction of the 

 machine, but in no case was there any marked change. 



A study of the effect of machine milking on the udder was made by A. S. 

 Alexander, who found no appreciable effect upon the physical condition of the 



