TRANSMISSION OF TOXINS THROUGH MILK 217 



none. Therefore, if a test shows that complement is present, the 

 conclusion is justified that the milk contains either mastitis milk 

 or colostrum. Mastitis milk can be distinguished from colostrum 

 milk by microscopic examination. The complement appears in 

 the milk when mastitis is in an early stage of development, so 

 the disease can be diagnosed by this method before clinical symp- 

 toms are pronounced. The test after Bauer and Sassenhagen is 

 made as follows: Three series of seven tubes each are filled in this 

 manner: The first series contains amounts of the milk to be 

 tested from 1 down to 0.1 c.c. and a tube without any. To the 

 milk is added enough physiologic salt solution to bring the volume 

 in each tube to 1 c.c. Then 0.2 c.c. inactivated sheep serum and 

 1 c.c. 1 per cent, suspension of washed rabbit corpuscles are 

 added to each tube. The contents are mixed and the tubes placed 

 in an incubator at 37 C. for two hours. The second series of 

 tubes is filled with the same material except that the milk is pre- 

 viously heated to 56 C. for thirty minutes. The third series 

 also contains the same material except that, in place of the test 

 milk, milk from a healthy cow is used. The cream should always 

 be removed from milks used for these tests. All tubes are incu- 

 bated for two hours at 37 C. 



Interpretation of Results. If the corpuscles have not laked, 

 they settle ,to the bottom of the tubes and the milk remains 

 white. If the milk is colored, some of the corpuscles have laked 

 and hemoglobin has gone into solution. Therefore, whenever a 

 tube shows that the milk is colored, complement was present. 

 The quantity of complement can be judged by the number of 

 tubes showing hemolysis. If much complement is present, tubes 

 1 to 6 are colored; if complement is present in small amounts, 

 only one or two are colored. The seventh tube, which contains 

 no milk, should never be colored, otherwise the sheep serum is 

 useless. The second series, which contains heated milk, never 

 shows hemolysis because the complement, if present, has been 

 destroyed by heat. This series, therefore, serves as a guide for 

 the first. 



Sometimes normal milk contains small amounts of complement. 

 The amount is usually so small that no hemolysis appears, but in 

 some cases slight laking may take place. For this reason the 

 third series of tubes has been prepared. This series contains 

 normal milk, and if hemolysis develops in this series it shows that 

 the suspension of sheep corpuscles is not in good condition. It is 

 well, therefore, to make preliminary tests of the sheep corpuscles 

 that are to be used, and find a suspension which shows no hemol- 

 ysis with normal cow's milk. 



If there are colored tubes in the first series the proof is at hand 



