138 MICROSCOPIC TESTS OF MILK. 



day is indeed fortunate if it has a corps of inspectors sufficient 

 to permit visiting each dairy four times a year. The conditions 

 existing and the difficulties of correcting them by inspection, 

 lead one to doubt whether anything but pasteurization can 

 give effective protection from streptococci. 



Bloody milk. Slight injuries to the udder will sometimes 

 cause the rupture of a blood vessel and result in the mixing of 

 blood with the milk. The blood may be so small in amount 

 as to escape notice by the milker. After delivery, when the 

 cream rises, it will be distinctly pink. Microscopic examina- 

 tion of the cream will reveal red blood corpuscles. To detect 

 the source of such milk, it maybe necessary to collect a sample 

 from each quarter of each cow's udder, in separate test tubes. 

 The bloody sample may be detected in the test, tube immedi- 

 ately after drawing, or certainly later after the cream has risen. 



REFERENCES. 



1. ARNOLD. Die Bedeutung der Fettsynthese, Fettphagocytose, Fett- 

 sekretion und Fettdegeneration fur die Milch- und Kolostrumbildun.^. 

 Munch.. Med. irc/nischr., 52. Jahrg., No. 18, 1905, S. 841. 



2. ARNOLD. The morphology of milk and colostrum secretion. 

 Beitr. Path. Anat. u. Allg. Path., Bd. XXXVIII, 1905, No. 2, S. 421. 

 Abs. in Exp. Sta. Rec., Vol. XVII, p. 495. 



3. BRRGKY. An investigation on the value of certain sanitary and 

 other precautionary measures, employed in the protection and marketing 

 of milk, upon the bacterial contents of the milk. l^nn. Dept. Agr. 

 Kept., 1900, Part I, p. 133. 



4. BERGEY. The cellular and bacterial content of cow's milk at dif- 

 ferent periods of lactation. Univ. Penn. 3 fed. />'///., Vol. XVII, July- 

 August, 1904, p. 181. 



5. BERGEY. The source and nature of bacteria in milk. /////. ,V<;. 

 125, Penn. Dept. Agr., 1904. 



6. BERGEY. The leucocyte and streptococcus content of cow's milk. 

 I 'uh'. Penn. JAY/. /;/., September, 1907. 



7. BRUNING. Investigations of market milk in 'Leipzig with special 

 reference to the presence of streptococci. Jahrb. Kindcrheilk. Bd. L,XII, 

 1905, No. 1, S. 1. Abst. in E.vp. Sta. Rec., Vol. XVII, 1906, No. 5, 

 p. 496. 



