MILK 455 



ful post-mortem examination. Examine material from 

 any caseous glands microscopically and inoculate 

 freely on to Dorset's egg medium. 



NOTE. Every post-mortem examination of animals infected 

 with tuberculous material should include the naked eye and 

 microscopical examination of the popliteal, superficial and deep 

 inguinal, iliac, lumbar and axillary glands on each side of the 

 body, also the retrohepatic, bronchial and sternal glands, the 

 spleen, liver and lungs (Fig. 215). 



(B) i. Intimately mix all the available cream and 

 deposit from the milk sample, and transfer to a sterile 

 Erlenmeyer flask. 



2. Treat the mixture by the antiformin method 

 (vide Appendix, page 502). 



3. Inoculate each of two guinea-pigs, intraperi- 

 toneally, with half of the emulsion thus obtained. 



4. Kill one of the guinea-pigs at the end of the first 

 week and examine carefully. 



5. Kill the second guinea-pig at the end of the second 

 week and examine carefully. 



6. Utilise the remainder of the deposit for micro- 

 scopical examination and cultivations upon Dorsett's 

 egg medium. 



NOTE. No value whatever attaches to the result of a micro- 

 scopical examination for the presence of the B. tuberculosis 

 unless confirmed by the result of inoculation experiments. 



6. Streptococcus Pyogenes Longus. 



(A) i . Spread serial surface plates upon nutrose agar. 

 Also plant serial cultivations upon sloped nutrient agar 

 (six tubes in series) . 



2 . If the resulting growth shows colonies which resem- 

 ble those of the streptococcus, make subcultivations 

 upon agar and in bouillon, in the first instance, and 

 study carefully. 



(B) i. Plant a large loopful of the deposit D 2 into 

 each of three tubes of glucose formate bouillon, and 

 incubate anaerobically (in Buchner's tubes) for twenty- 

 four hours at 3 7 C. 



