Dietary supplementation protects honey bee from immunosuppression caused by Nosema ceranae

Previous studies demonstrated that microsporidium Nosema ceranae exerts negative impact on honey bee health, including down-regulation of immune-related genes. The aim of this study was to evaluate if dietary amino-acid and vitamin supplement “BEEWELL AminoPlus” may protect honey bees from immunosuppression induced by N. ceranae. For that purpose we set up six groups with 40 bees in each. In four groups, we infected bees with N. ceranae and applied supplement at different moments after emergence (on first, third, sixth and ninth day after emergence). Two control groups were established, one with infected bees and fed without addition of supplement, and the other one with bees that were neither infected nor supplemented. Expression of genes for immune-related peptides (abaecin, apidaecin, hymenoptaecin, defensin and vitellogenin) was compared among groups. The results revealed significantly lower Nosema load in groups supplemented with “BEEWELL AminoPlus” than in control group (infected with N. ceranae but not treated with supplement), especially on 12th day post infection. On 12th day post infection, the expression levels of apidaecin, hymenoptaecin, defensin and vitellogenin were significantly higher in bees that received the supplement suppressed compared to control bees. These results suggest that tested supplement “BEEWELL AminoPlus” may protect honey bees from induced immunosuppression. The supplement exerted the best efficacy when applied simultaneously with Nosema infection suggesting early spring as the best moment for supplement application because Nosema spore load in hive is highest during that period.