Studies on the Effect of Infection with Nosema apis on the Physiology of the Queen Honey-bee

When a queen honey-bee becomes infected with Nosema apis, the result can be very serious indeed for her colony. The metabolic processes are disturbed by the damage done by the parasite to the epithelial cells of the mid-gut, and this apparently leads to severe damage to the ovaries, at first by the production of a high proportion of eggs that fail to hatch, and ultimately by complete cessation of ovi-position and supersession or death of the queen. In the case of Nosema bombycis, which attacks the silk moth, infection is carried from the female to her offspring via the egg; but there is no evidence that this ever occurs in the case of Nosema apis. Although large numbers of eggs, larvae, and pupae produced by infected queen honey-bees were examined, none was found to be infected with any stage of Nosema apis.