What are the common symptoms of Nosema disease in honey bees?

Nosema disease in honey bees, caused by the microsporidian parasites Nosema apis and Nosema ceranae, manifests primarily through symptoms that affect the digestive system of the bees. Dysentery, characterized by the outbreak of watery feces in and around the hive, is a common indicator of this disease. The parasite damages the intestinal lining, leading to reduced nutrient absorption. Consequently, this can also contribute to decreased brood production since a weakened or stressed hive cannot effectively care for its young.

Increased brood production requires the colony to be in good health, with adequate nutrition and vitality. When Nosema infection is present, the overall health of the bees is compromised, resulting in fewer eggs being laid by the queen and higher mortality rates among immature bees.

The other options present symptoms that do not typically align with Nosema infestation. Decreased honey production and increased foraging may occur, but they are not the primary indicators of the disease. Likewise, lethargy combined with increased hive activity and swarming behaviors with excessive queen cells point to different colony stresses or behaviors, rather than specifically to Nosema infection. Hence, the accurate identification of symptoms is crucial for effective diagnosis and management of honey bee health issues.