200 CLINICAL BACTERIOLOGY 



bacteriotropic and bacteriolytic elements of the blood, 

 which find their outlet by the milk stream. We know 

 opsonins are to be found in the urine and in the perspira- 

 tion, and why not in the milk, which, in addition to being 

 a secretion, is also an excretion up to a point. And if this 

 is true of opsonins, why not the other antibodies of the 

 blood also ? A system so depleted of its protective anti- 

 bodies must therefore be liable to bacterial attacks, and 

 more so if these antibodies are specific to the causative 

 bacteria. 



We have over and over again noticed cows suffering 

 from tuberculosis in a moderately mild form give a larger 

 volume of milk per diem than cows deemed free from the 

 disease, but it would appear to be the quantity is increased 

 at the expense of the quality. These cows are generally in 

 very poor condition, and even in advanced stages of 

 emaciation. Now, if such cows are allowed to become 

 :c dry/' it is astonishing how the symptoms common to 

 tuberculosis abate, and the animal begins to thrive and 

 often do well, and in time an apparent complete cure 

 follows. 



Some practitioners will explain that this is due to a check 

 upon the nutritive material in the form of milk leaving the 

 system and disturbing the metabolism. This may be, and 

 undoubtedly is, true up to a point, but that fact would not 

 in itself sufficiently explain the improvement taking place 

 in the diseased organs. This improvement, we believe, is 

 brought about by a rise in the opsonic index owing to a 

 check upon the outflow of opsonin into the milk stream ; 

 and, of course, an increase of opsonin in the system means 

 a more powerful offensive and defensive force attacking the 

 invading bacteria, and bringing about their destruction, and 

 the restoration of the patient to a more healthy standard. 



