Archive image from page 14 of Diagnosing bee diseases in the. Diagnosing bee diseases in the apiary . diagnosingbeedi392burn Year: 1936 DIAGNOSING BEE DISEASES IN THE APIARY 13 would normally be spinning their coccoons (figs. 8, /-Z, and 10, D-F). Comparatively few larvae die while fully extended (fig. 10, A, B, (7, G, H, I). Pupae are rarely affected by this disease. Figure 9.—European foulbrood ; heavily infected comb showing larvae in various stages of disease and decay. Larvae dead of European foulbrood, therefore, are usually coiled on the bottom of the cells but may be irregularly tw
Archive image from page 14 of Diagnosing bee diseases in the. Diagnosing bee diseases in the apiary . diagnosingbeedi392burn Year: 1936 DIAGNOSING BEE DISEASES IN THE APIARY 13 would normally be spinning their coccoons (figs. 8, /-Z, and 10, D-F). Comparatively few larvae die while fully extended (fig. 10, A, B, (7, G, H, I). Pupae are rarely affected by this disease. Figure 9.—European foulbrood ; heavily infected comb showing larvae in various stages of disease and decay. Larvae dead of European foulbrood, therefore, are usually coiled on the bottom of the cells but may be irregularly twisted or fully extended. COLOR OF THE DEAD BKOOD Soon after death larvae become dull and grayish or yellowish- white. During decay the color deepens and may become brown or almost black. The tracheae, or breathing tubes, in dead larvae usu- ally show more clearly than in healthy ones (fig. 8, C and F). They appear as radiating white lines in the dead coiled larvae and as narrow white lines across larvae that die while extended. A white line which crosses the radiating white lines can frequently be seen on the side of dead larvae. The prominence of the tracheae is a valuable symptom of European foulbrood but is not strictly depend- able. An elongated, dull grayish-white or yellowish-white mass can be seen through the skin along the back of sick and recently dead larvae. This mass is within the chyle stomach and consists of a turbid fluid that contains many bacteria. In healthy larvae, pollen in the stomach can often be seen through the skin along the back (fig. 8, J), but the color is usually of a brighter and deeper shade
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