Honeybees (Apis mellifera) are constantly exposed to a wide variety of environmental stressors such as parasites and pesticides. Among them, Nosema ceranae and neurotoxic insecticides might act in combination and lead to a higher honeybee mortality. We investigated the molecular response of honeybees exposed to N. ceranae, to insecticides (fipronil or imidacloprid), and to a combination of both...

Microbial pathogens are thought to have a profound impact on insect populations. Honey bees are suffering from elevated colony losses in the northern hemisphere possibly because of a variety of emergent microbial pathogens, with which pesticides may interact to exacerbate their impacts. To reveal such potential interactions, we administered at sublethal and field realistic doses one neonicotino...

Sex-related differences in susceptibility to pathogens are a common phenomenon in animals. In the eusocial Hymenoptera the two female castes, workers and queens, are diploid and males are haploid. The haploid susceptibility hypothesis predicts that haploid males are more susceptible to pathogen infections compared to females. Here we test this hypothesis using adult male (drone) and female (wor...

The microsporidian parasite designated here as Nosema sp. Isolate YNPr was isolated from the cabbage butterfly Pieris rapae collected in Honghe Prefecture, Yunnan Province, China. The genome was sequenced by Illumina sequencing and compared to those of two related members of the Nosema/Vairimorpha clade, Nosema ceranae and Nosema apis. Based upon assembly statistics, the Nosema sp. YNPr genome ...

Nosema ceranae, a newly introduced parasite of the honey bee, Apis mellifera, is contributing to worldwide colony losses. Other Nosema species, such as N. apis, tend to be associated with increased defecation and spread via a fecal-oral pathway, but because N. ceranae does not induce defecation, it may instead be spread via an oral-oral pathway. Cages that separated older infected bees from you...

Western honey bees (Apis mellifera) face an increasing number of challenges that in recent years have led to significant economic effects on apiculture, with attendant consequences for agriculture. Nosemosis is a fungal infection of honey bees caused by either Nosema apis or N. ceranae. The putative greater virulence of N. ceranae has spurred interest in understanding how it differs from N. api...

Honey bees (Apis mellifera) are important pollinators and their health is threatened worldwide by persistent exposure to a wide range of factors including pesticides, poor nutrition, and pathogens. Nosema ceranae is a ubiquitous microsporidian associated with high colony mortality. We used lab micro-colonies of honey bees and video analyses to track the effects of N. ceranae infection and expos...

Identification of transmission routes and of factors affecting the spatial positions of pathogens, hosts and vectors is basic to an adequate disease management. Nosema ceranae is a Microsporidian recently described as a parasite of Apis mellifera honeybees and is currently considered the aetiological agent of an emergent illness named nosemosis type C. In this article we evaluate the role of a ...

Microsporidium Nosema ceranae is well known for exerting a negative impact on honey bee health, including down-regulation of immunoregulatory genes. Protein nutrition has been proven to have beneficial effects on bee immunity and other aspects of bee health. Bearing this in mind, the aim of our study was to evaluate the potential of a dietary amino acid and vitamin complex "BEEWELL AminoPlus" t...

Since 2006, beekeepers have reported increased losses of Apis mellifera colonies, and one factor that has been potentially implicated in these losses is the microsporidian Nosema ceranae. Since N. ceranae is a fairly recently discovered parasite, there is little knowledge of the variation in infection levels among individual workers within a colony. In this study we examined the levels of infec...