Host parasite interactions

Host parasite interactions

2

Table 28-13

4

Table 28-25

Fig. 1-15KOCHS POSTULATESTools:DiseasedanimalHealthyanimalRedbloodcellObserveblood/tissueunder themicroscopeRedbloodcellThe Postulates:1. The suspected pathogenic organism should be present in all cases of the disease and absent from healthy animals.2. The suspected organism should be grown in pure culture.SuspectedpathogenMicroscopy, stainingNoorganismspresentStreak agar platewith sample from eitherdiseased orhealthy animalColonies ofsuspectedpathogenLaboratory culture3. Cells from a pure culture of the suspected organism should cause disease in a healthy animal.Experimental animalDiseased animalInoculate healthy animal withcells of suspected pathogenRemove blood or tissue sampleand observe by microscopyLaboratorycultureSuspectedpathogenLaboratory reisolation4. The organism should be reisolated and shown to be the same as the original.Pure culture(must besameorganismas before)6

7

8

Table 28-39

10

11

Table 28-412

13

14