. American bee journal. Bee culture; Bees. entirely to food or climatic condi- tions. No race of honeybees, as far as is known, is entirely immune to the dis- ease. Worker, drone and queen larvae are susceptible to infection; the adult bees are not. The inciting cause of the disease is a gerin which is called Bacillus lar- vae. When this parasite is added to honey or .=yrup and fed to a healthy colony the disease is produced (Fig. 1). It is a small rod-shaped plant (Fig. 2) that can be seen only by the use of a microscope, and then only when it is magnified 600 diameters or more. It produces s
. American bee journal. Bee culture; Bees. entirely to food or climatic condi- tions. No race of honeybees, as far as is known, is entirely immune to the dis- ease. Worker, drone and queen larvae are susceptible to infection; the adult bees are not. The inciting cause of the disease is a gerin which is called Bacillus lar- vae. When this parasite is added to honey or .=yrup and fed to a healthy colony the disease is produced (Fig. 1). It is a small rod-shaped plant (Fig. 2) that can be seen only by the use of a microscope, and then only when it is magnified 600 diameters or more. It produces spores, which are somewhat like seed (Fig. 3). These spores (Fig. 4) are so small that if 20,000 of them were placed end to end, they would measure only about one inch. They live over long periods and are very difficult to destroy, either by heat or chemical Fig. .1—American foulbrood produced experimentally. Fig. 3.—Bacillus larvae, spore formation. The spores are taken into the stom- ach of the larva with the food. They then germinate, and the growing form of the parasite reaches the blood and other parts of the body. This causes the larva to become sick, and in about one week to die. Sometimes the pupal stage is reached before death takes place. The body of each dead larva and pupa (Fig. 5) contains mil- lions of spores. These are capable of producing the disease should any of them reach healthy larva; and be eaten by them. Symptoms of American Foulbrood Inasmuch as the practical apiarist is interested in the colony rather than the individual bee, it is well in dis- cussing the symptoms of any bee dis- ease to consider the colony as the unit. Any evidence of disease that is obtained from a larva, pupa or adult bee is, in fact, a colony symptotn. The death of brood or adult bees is fre- quently the first symptom that is noted. In the brood diseases it is only the brood that dies; the adult bees do not even become infected. In American foulbrood the brood is
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Keywords: ., bo, bookcentury1800, bookdecade1860, booksubjectbees, bookyear1861
