292 STATE BUAKD OF ACfKICUI.TURE. 



The carelessness with whidi milk pails are handled is a mailer of no lillle moment. 

 In Ihe dairy Ihey may be cleaned perfectly, bul what is j,'ained if they are taken to the 

 l>arn or stable and exposed to the dust tlirou;:li bt-ddin^r and feedinj,' and sometimes 

 cleaning;. It has been shown in connection with the study of the stable dust, how 

 pernicious such a jiraclice is in inoiuhitinj,' tlie ])ail witli millions of oimoxious bac- 

 teria. Under the discussion of aerators, coolers and cans, more will be said pertinent 

 to this subject. 



We are now ready to make some estimates of the number of bacteria reaching the 

 milk duriufjj the ]>rocess of milkinfi. For this determination, ])lates were exposed next 

 to the pail for dillcrent periods of time. The conditions under which these exposures 

 were made may be rej^arded as sli^ditly above the average. The number of bacteria 

 developing in the plates range from foiir thousand to eighty thousand during one minute 

 of time, or the number of bacteria falling into a twelve quart ])ail during one minute 

 of time would be in round niunbcrs from forty-eight to seven hundred twenty thousands. 

 Allowing live minutes for milking, the n\imber would l)e multii)lied by five, or from 

 two hundred forty thousand to three millions six hundred thousands. The author 

 has made independent estimates as high as nine millions. In this rough estimate, 

 the fact that only a fraction of the real number of bacteria find their way into the 

 milk can be profitably taken into consideration. This inexactness is due to the in- 

 solubility of particles of dirt and dung in the gelatin and to our inability to make a 

 correct count of the number of bacteria on hairs, shreds and substances of like nature. 

 The great variation in the n\imber of bacteria is principally due to the cleanliness 

 of the cow, some are mucli cleaner than others under ordinary conditions. It has 

 not been possible for us to make an estimate of the nund^er of bacteria getting into the 

 milk in the first or third classes or types mentioned ])reviously. Wliat we have gives 

 some idea of a type between the first and second, but nearer the second. 



There is no factor so important in handling milk as the milking process itself. 

 for with a little care much tilth may be avoided and a comparatively clean milk may 

 be obtained — as clean as it is possible under the circumstances. At this point all of 

 the agents which have been discussed are centered, — the dust of the barn or stal)le, the 

 hair of the cow, particles of dung and dirt, shreds of straw or other substances, the care 

 of the stable floor, the cleanliness of the milker's hands and clothes, and the condition 

 of the pail, all exert a greater or less influence upon the act of milking. Here will be 

 found failure or success in dairy operations. If a dairyman can control his work 

 satisfactorily thus far, the steps remaining ought to be easily managed. Again, a 

 milk comparaiively free from bacteria or other micro-organisms to start toith, may he 

 easily controlled ihcrmfter. 



It is quite a ditiirult matter to secure a milk from the udder of the cow fiee fiom 

 bacteria. Bolley and Ward have demonstrated this, but it is possible to obtain a milk 

 that is practically pure, and usually will not readily undergo change. In this labora- 

 tory, the author drew from thirty diflferent quarters of cows' udders by means of 

 sterile flasks and milk tubes, after milking out a little of the fore milk, thirty different 

 samples, thirteen of which at the end of six months placed at the temperature of the 

 living room had not undergone any appreciable cliange. This does not mean that they 

 were necessarily germ free, but that the germs did not act upon the milk to materially 

 change it. It is the experience of those who have made a special study of milk taken 

 from the udders of cows that many of the bacteria found in the udders h.ave no influ- 

 ence upon the milk. For practical dairying this may be disregarded largely, as far 

 as the keeping qualities of the milk are concerned, but should not be lost sight of when 

 any obnoxious germ is causing trouble in the dairy. 



Before leaving the stable, it nniy be well to call attention to a habit which some 

 dairymen or milk-producers have of permitting decaying substances to remain about 

 the barn or stable. T have seen decomposinir flesh, rotten beet pulji and other such sub- 

 stances in or within reach of the milking stable. Aside from the odors which emanate 

 from decomposing sul)stances. and which may be absorbed by the milk, there is a grave 

 chance of some of the micro-organisms of decomposition finding their way into the 

 milk and producing intensely toxic or poisonous products. Carelessness of this sort 

 mav be fittingly regarded as criminal. 



What the true significance of aeration of milk may be is a question difficult to 

 answer at the present time. However, when we inhale the foul odors coming from 

 the milk during the process of aeration, the value seems to be apparent When milk 

 is passing through the separator, the same foul air is noticeable, coming from the 

 delivery tubes. These facts in connection with the experience of practical dairymen 

 indicate that this step is one of great value, yet there are those who maintain that 

 the mere aeration of milk does not enhance its value. Perhaps in not the far distant 



