CULTURE MEDIA 



69 



I. Culture Media. — Differences in the quality of the meat 

 used in making the meat infusions has given some marked varia- 

 tions in the quantitative results. Meat extracts from younger 

 animals give higher counts than do extracts from the meat of 

 older animals. Again, the prepared extracts of the different 

 packing houses give different results and the results obtained 



Ovol of the PoLrevsitic Worms of Man 

 NEMATODA 



DRAWN TO SCALd X ICOO 



/— X, ATShowing ff^ 

 /^Ov sides syiS-f \ > 

 / ^Bra\ metrically ' > ' j 



;S^g% 1 convex } ' I 



Oxyuris ^ 

 vermlcularisA.B 



z 

 

 a 

 



i- 





 



A.- Median focus BrSurface focus 



/Modilied from SlileajgoA (»rter Stilea.l9(U\ 

 \and LoosilWi ) ^ I 



R-Tumed 



fria over to 

 ^Laa,\ show one 

 ««™>sJdefiRtten- 



f Modilied from SI 

 \and Loosa.l9<U 



D.-Ati-pical. unfertilized 



eclg (after Loo3S.I90jJ 



Strongylus /^, 



(ftrter Looi^, 1905) f T 



"^ mi 



C-without outer 'irX' jl Necator 

 eiiveiope(M.rfif.cdiV'l ' &niericevnus /, 



Ascexris 

 lumbricoides ^«»^ iMoa,<.ir„ 

 A.B. CD. Trichuris '■=....iv«sj 

 trichiura 



lOrigirial) 



V. Embiyo 



'" In stool 



^^. after 12 to 48 



Agchylostoma 

 ,,/ duodenale 



Loos&tou^l 



, ^b Acfchylostonia 



h^'-^^iJ^ , duodenale Fmbrvu. 



^Lo«...iws) „ 'n fr<;sh Stool 



Strongyloides 

 stercoralis , " 



USAayaJMcdJca/Se/ioo/. 



Fig. 22. — Intestinal ova. Nematodes. — {Stitt.) 



from the use of media made with manufactured meat extracts 

 differ from those obtained from the use of the laboratory made 

 meat infusions. In fact most workers are opposed to the use of 

 the manufactured meat extracts because of the fact that they are 

 mixed products and also because of the uncertainty of the amount 

 and number of the added ingredients any or all of which may 



