9. Have a succession of cases occurred at intervals of several days or weeks, irrespective of weather? Suggestive of lung plague.
10. Have the indications of consolidated lung been early and over extensive undivided areas? Like lung plague.
11. Have cases been milder in cold dry weather and more violent in hot and moist? Such is lung plague.
12. Does the same subject present lung lesions of very different ages;—infiltration with tough, elastic lung; red hepatization; gray hepatization; black infarction; sequestra, etc.? Bespeaks lung plague.
13. Do the infiltration and red hepatization show a marbling with very extensive filling and turgidity of the interlobular and subpleural connective tissue, and abundant effusion into the chest? This is the nature of lung plague.
14. Does the lung exudate when inoculated in the tail of a susceptible bovine animal (one that has never had the disease), produce local inflammation and exudation and procure immunity? This characterizes lung plague. Does it fail to cause inoculation swelling, in an animal that had lung plague. Lung plague is still more indicated.
15. If the disease has lasted long enough in a place to determine, has it affected any other than bovine animals, and does inoculation of the lung exudate into any other genus of animal cause the disease? Other genera are immune from lung plague.
Tuberculosis is distinguished by the habitual absence of the high temperature, the numerous circumscribed areas of flatness with wheezing or other abnormal lung sounds, in the midst of a general field giving the normal respiratory murmur, by the enlargement or induration of superficial lymph glands, by the response to the tuberculin test, and by the lung tubercles and diseased lymph glands,—congested, indurated, caseated, calcified—found at the necropsy. Inoculation of other genera causes tuberculosis.
Simple bronchitis is usually connected with climatic change or exposure, tends to affect a number at once, gives the blowing and mucous râles, without indications of extended lung consolidation or pleural effusion, and after death does not furnish lesions of all ages, recent and remote.
Verminous bronchitis, attacks the young only or mainly, and never seriously injures the mature, involves all or nearly all the young in the herd, shows less hyperthermia, and less extensive consolidation, more wheezing in the lungs, and a free expectoration in which the worms (embryos or adults) may be found by careful search.